STANDARD OPERATING SAFETY GUIDES
OSWER Directive 9285.1-01B
November 1984
ENVIRONMENTAL RESPONSE BRANCH
HAZARDOUS RESPONSE SUPPORT DIVISION
OFFICE OF EMERGENCY AND REMEDIAL RESPONSE
U.S. ENVIRONMENTAL PROTECTION AGENCY
-------
TABLE OF CONTENTS
Environmental Incidents, Part 1 Page 1-1
Standard Operating Safety Procedures, Part 2 Page 2-1
Site Entry- General Measures and Requirements, Part 3 Page 3-1
Site Entry - Survey and Reconnaissance, Part 4 Page 4-1
Site Entry - Levels of Protection, Part 5 Page 5-1
Site Control - Work Zones, Part 6 Page 6-1
Site Control - Decontamination, Part 7 Page 7-1
Annex 1 - Level A Decontamination Page Al-1
Annex 2 - Level B Decontamination Page A2-1
Annex 3 - Level C Decontamination Page A3-1
Annex 4 - Level A Decontamination, Minimum Layout Page A4-1
Air Surveillance, Part 8 Page 8-1
Annex 5 - Guide to Environmental Response Team's Page A5-1
Air Surveillance Program
Annex 6 - Organic Solvents in Air Page A6-1
Site Safety Plan, Part 9 Page 9-1
Annex 7 - Emergency Operation Codes Page A7-1
Annex 8 - Response Safety Check-Off Sheet Page A8-1
Annex 9 - Site Safety Plan Page A9-1
Annex 10 - Sample Safety Plan Page A10-1
Appendix I - Characteristics of the HNU Photoionizer Page 1-1
and Organic Vapor Analyzer
Appendix II - Rationale for Relating Total Atmospheric Page II-l
Vapor/Gas Concentrations to the Selection
of the Level of Protection
Appendix III - Dermal Toxicity Data Page lli-1
-------
PART 1
ENVIRONMENTAL INCIDENTS
I. INTRODUCTION
An environmental incident involves a release or threat of a release
of hazardous substances that pose an imminent and substantial danger
to public health and welfare or the environment. Each incident pre-
sents special problems. Response personnel must evaluate these prob-
lems and determine an effective course of action to mitigate the
incident.
Any incident represents a potentially hostile situation. Chemicals
that are combustible, explosive, corrosive, toxic, or reactive, along
with biological and radioactive materials can affect the general pub-
lic or the environment as well as response personnel. Workers may
fall, trip, be struck by objects, or be subject to danger from elec-
tricity and heavy equipment. Injury and illness may also occur due
to physical stress and climate. While the response activities needed
at each incident are unique, there are many similarities. One is
that all responses require protecting the health and ensuring the
safety of the responders.
II. EXPOSURE TO TOXIC SUBSTANCES
Toxic (including radioactive material and etiological agents) or
chemically active substances present a special concern because they
can be inhaled, ingested, absorbed through the skin, or destructive
to thje skin. They may exist in the air or due to site activities
become airborne or splash on the skin. The effects of these sub-
stances can vary significantly. Ingested or inhaled the substances
can cause no apparent illness or they can be fatal. On the skin they
can cause no demonstrable effects. Others however can damage the
skin, or be absorbed, leading to systemic toxic effects.
Two types of potential exposure exist:
- Acute: Exposures occur for relatively short periods of time,
— generally hours to 1-2 days. Concentrations of toxic air contam-
inants which may be inhaled are high relative to their protection
criteria. In addition, substances may contact the skin directly
through splashes, immersion, or air with serious results.
- Chronic: Exposures occur over longer periods of time, generally
months to years. Concentrations of toxic air contaminants which
may be inhaled are relatively low. Direct skin contact by immer-
sion, splash, or air involves substances exhibiting low dermal
activity.
1-1
-------
In general, acute exposures to chemicals in air are more typical in
transportation accidents, fires, or releases at chemical manu-
facturing or storage facilities. Acute air exposures do not persist
for long periods of time. Acute skin exposures occur when workers
must be close to the substances in order to control the release
(patching a tank car, off-loading a corrosive material, etc.) or
contain and treat the spilled material. Once the immediate problems
have been alleviated, exposures tend to become more chronic in nature
as cleanup progresses.
Chronic exposures usually are associated with longer-term remedial
operations. Contaminated soil and debris from emergency operations
may be involved, soil and ground water may be polluted, or impound-
ment systems may contain diluted chemicals. Abandoned waste sites
represent chronic problems. As activities start at these sites,
however, personnel engaged in sampling, handling containers, bulking
compatible liquids, etc. face an increased risk of acute exposures
to splashes, or the generation of vapors, gases, or particulates.
At any specific incident, the hazardous properties of the materials
may only represent a potential threat. For example, if a tank car of
liquified natural gas involved in an accident remains intact, the
risk from fire and explosion is low. In other incidents, hazards are
real and risks high as when toxic or flammable vapors are being re-
leased. The continued health and safety of response personnel
requires that the hazards - real or potential - at an episode be
assessed and appropriate preventive measures instituted.
III. HEALTH AND SAFETY OF RESPONSE PERSONNEL
To reduce the risks to workers responding to hazardous substance
incidents, an effective health and safety program must be implemented.
This would include, as a minimum:
- Safe work practices.
- Engineered safeguards.
- Medical surveillance.
- Environmental and personnel monitoring.
- Personnel protective equipment.
- Education and training.
- Standard operating safety procedures.
1-2
-------
As part of a comprehensive program, standard operating safety ^rc-
cedures provide instructions on how to accomplish specific tasks in a
safe manner. In concept and principle, standard operating safety-
procedures are Independent of the type of incident. Their appli-
cability at a particular incident must be determined and necessary
modifications made to match prevailing conditions. For example,
personnel protective equipment, in principle, is an initial con-
sideration for all incidents; however, its need and the type of
equipment required is based on a case-by-case evaluation. Likewise,
someone must make the first entry onto a site. The exact entry
procedure to be used can only be determined after assessing the
conditions prevailing at that incident.
The purpose of this document is to provide standard operating safety
guides related to site control and entry. The guidance included is
not meant to be a comprehensive treatment of the subjects covered.
Rather, it is meant to be used to complement professional training,
experience, and knowledge.
IV. OCCUPATIONAL HEALTH AND SAFETY POLICY
EPA's Occupational Health and Safety staff is responsible for devel-
oping, supporting, and evaluating a program to protect the health and
safety of EPA employees. The Standard Operating Safety Guides comple-
ment, and supplement the policies, procedures, and practices contained
in EPA's Occupational Health and Safety Manual, in particular, with
Chapter 9 - Hazardous Substances Responses, EPA Order 1440.2 - Health
and Safety Requirments for Personnel Engaged in Field Activities, and
EPA Order 1440.3 - Respiratory Protection.
1-3
-------
PART 2
STANDARD OPERATING SAFETY PROCEDURES
1. GENERAL
There are many guides or procedures for performing ttie variety of
tasks associated with responding to environmental episodes involving
hazardous substances. These may be administrative, technical , or
management-oriented. All these procedures are intended to provide
uniform instructions for accomplishing a specific task. In addition
to other types of procedures, safety-oriented operating procedures
are needed. The purpose of this document is to provide selected
standard operating safety guides which can be used to develop more
specific procedures.
11. DEVELOPMENT OF STANDARD OPERATING SAFETY PROCEDURES
A major consideration in responding to accidental releases of hazard-
ous substances or incidents involving abandoned hazardous waste sites
is the health and safety of response personnel. Not only must a
variety of technical tasks be conducted efficiently to mitigate an
incident, but they must be accomplished in a manner that protects the
worker. Appropriate equipment and trained personnel, combined with
standard operating procedures, help reduce the possibility of harm to
response workers.
For procedures to be effective:
- They must be written in advance. Developing and writing safe,
practical procedures is difficult when prepared under the stress
of responding to an incident.
- They must be based on the best available information, operational
principles, and technical guidance.
- They must be field-tested, reviewed, and revised when appropriate
by competent safety professionals.
i_ They must be understandable, feasible, and appropriate.
- All personnel involved in site activities must have copies of
the safety procedures and be briefed on their use.
- Response personnel must be trained and periodically retrained
in personnel protection and safety.
2-1
-------
III. RESPONSE ACTIVITIES
Many of the procedures involved in response activities are primarily
concerned with health and safety. In concept and principle, these
are generic and independent of the type of incident. They are adapted
or modified to meet site-specific requirements. Each hazardous
materials incident must be evaluated to determine its hazards and
risks. Various types of environmental samples or measurements may be
needed initially to determine the hazards or to provide additional
information for continuing assessment. Personnel must go on-site to
accomplish specific tasks. Efforts are required to prevent or reduce
harmful substances from migrating from the site due to natural or
human activities. Containment, cleanup, and disposal activities may
be required. Each of these activities requires that safety procedure
be. developed or existing procedures be adapted so that response
personnel are protected.
IV. OPERATING GUIDES
The standard operating safety guides that follow cover primarily site
control and entry. These guides illustrate technical considerations
necessary in developing standard instructions. For a given incident,
the procedures recommended should be adapted to conditions imposed by
that specific situation.
2-2
-------
PART 3
SITE ENTRY - GENERAL MEASURES AND REQUIREMENTS
1. INTRODUCTION
Personnel responding to environmental episodes involving chemical
substances encounter conditions that are unsafe or potentially unsafe.
In addition to the danger due to the physical, chemical, and toxico-
logical properties of the material present, other types of hazards
electricity, water, heavy equipment, falling objects, loss of balance,
or tripping, for example - can have an adverse effect on personnel.
This part discusses safety measures and precautions associated only
with the hazardous nature of chemical compounds.
11. SAFETY PRACTICES
A. Personal Precautions
Eating, drinking, chewing gum or tobacco, smoking, or any
practice that increases the probability of hand-to-mouth
transfer and ingestion of material is prohibited in any area
designated contaminated.
- Hands and face must be thoroughly washed upon leaving the
work area.
- Whenever decontamination procedures for outer garments are in
effect, the entire body should be thoroughly washed as soon
as possible after the protective garment is removed.
- No facial hair which interferes with a satisfactory fit of
the mask-to-face-seal is allowed on personnel required to
wear respirators.
- Contact with contaminated or suspected contaminated surfaces
should be avoided. Whenever possible, do not walk through
puddles, leachate, discolored surfaces, kneel on ground, lean,
sit, or place equipment on drums, containers, or the ground.
- Medicine and alcohol can potentiate the effects from exposure
to toxic chemicals. Prescribed drugs should not be taken by
personnel on response operations where the potential for
absorption, inhalation, or ingestion of toxic substances
exists unless specifically approved by a qualified physician.
Alcoholic beverage intake should be minimized or avoided
during response operations.
3-1
-------
B. Site Safety Plans
- A Site Safety Plan must be developed for all phases of site
operations and made available to all personnel. Unless time
precludes- it, the plan must be written and posted.
All personnel must be familiar with standard operating safety
procedures and any additional instructions and information
contained in the Site Safety Plan.
All personnel must
Site Safety Plan.
adhere to the information contained in the
C. Operations
All personnel going on-site must be adequately trained and
thoroughly briefed on anticipated hazards, equipment to be
worn, safety practices to be followed, emergency procedures,
and communications.
Any required respiratory protective devices and clothing must
be worn by all personnel going into areas designated for
wearing protective equipment.
Personnel on-site must use the buddy system when wearing
respiratory protective equipment. As a minimum, a third
person, suitably equipped as a safety backup, is required
during initial entries.
Visual contact must be maintained between pairs on-site and
safety personnel. Entry team, members should remain close
together to assist each other during emergencies.
During continual operations, on-site workers act as safety
backup to each other. Off-site personnel provide emergency
assistance.
Personnel should practice
doing the actual procedure.
unfamiliar operations prior to
Entrance and exit locations must be designated and emergency
escape routes delineated. Warning signals for site evacuation
must be—established.
Communications using radios, hand signals, signs, or other
means must be maintained between initial entry members at all
times. Emergency communications should be prearranged in
case of radio failure, necessity for evacuation of site, or
other reasons.
3-2
-------
- Wind Indicators visible to all personnel should Se sfit--
gically located throughout the site.
- Personnel and equipment In the contaminated area should t~
minimized, consistent with effective site operations.
- Work areas for various operational activities must be estat-
lished.
- Procedures for leaving a contaminated area must be planned
and implemented prior to going on-site. Work areas ar;
decontamination procedures must be established based on
expected site conditions.
III. MEDICAL PROGRAM
To safeguard the health of response personnel, a medical program mus
be developed, established, and maintained. This program has t.w
essential components: routine health care and emergency treatment
A. Routine Health Care
Routine health care and maintenance should consist of at least
- Pre-employment medical examinations to establish the ind1
vidual's state of health, baseline physiological data, a
ability to wear personnel protective equipment. The fr
quency and type of examination to be conducted thereaft
should be .determined by medical personnel knowledgeable
the area of toxicology.
- Arrangements to provide special medical examinations, car
and counseling in case of known or suspected exposures
toxic substances. Any special tests needed depend on t
chemical substance to which the individual has been expos*
B. Emergency Medical Care and Treatment
The Medical Program must address emergency medical care
treatment of response personnel, including possible exposures
toxic substances and injuries resulting from accidents or physi
hazards. The following items should be included in emerge
care provisions:
- Name, address, and telephone number of the nearest medi
treatment facility. This should be conspicuously post
A map and directions for locating the facility, plus
travel time, should be readily available.
- The facility's ability to provide care and treatment
personnel exposed or suspected of being exposed to toxic
3-3
-------
otherwise hazardous). If the facility lacks toxicological
capability, arrangements should be made for consultant
services.
Admi rri strati on arrangements for accepting patients.
Arrangements to quickly obtain ambulance, emergency, fire,
and police services. Telephone numbers and procedures for
obtaining these services should be conspicuously posted.
Emergency showers, eye wash fountains, and first aid equipment
readily available on-site. Personnel should have first aid
and medical emergency training.
Provisions for the rapid identification of the substance to
which the worker has been exposed (1f this has not previously
been done). This information must be given to medical person-
nel .
Procedures for decontamination of injured workers and pre-
venting contamination of medical personnel, equipment, and
faci1ities.
IV. EDUCATION AND TRAINING
All personnel involved in responding to environmental incidents must
be trained to carry out their response functions. Training must be
provided in the use of all equipment, including respiratory protective
apparatus and protective clothing; safety practices and procedures;
general safety requirements; advanced first aid; and hazard recogni-
tion and evaluation.
Safety training must be a continuing part of the total response
program. Periodic retraining and practice sessions not only create
a high degree of safety awareness, but also help to maintain profi-
ciency In the use of equipment' and knowledge of safety requirements.
V. QUALIFIED SAFETY PERSONNEL
Personnel responding to chemical incidents must make many complex
decisions regarding safety. Making these decisions correctly re-
. quires nwe than elementary knowledge. For example, selecting the
most effective personnel protective equipment requires not only
expertise in the technical areas of respirators, protective clothing,
air monitoring, physical stress,-etc., but also experience and profes-
sional judgment. Only a competent, qualified person (specialist) has
the technical judgment to evaluate a particular incident and determine
the appropriate safety requirements. This individual, through a
combination of professional education, on-the-job experience, special-
3-4
-------
i zed training, and continual study, acquires expertise to make sound
decisions.
VI. STRESS
A. Introduction
Both physiological and psychological stress effect response
personnel. Under certain conditions, stress contributes signif-
icantly to accidents and harms workers in other ways. To reduce
the potential for abnormal physical stress or mental anxiety:
- Workers must be periodically examined by medical authorities
to determine if they are physically, and if possible, psycho-
logically fit to perform their jobs.
- Continual practice and training must be provided 1n using
personnel protective equipment, especially the self-con-
tained breathing apparatus and chemical-resistant protective
clothing.
- An effective safety program must be implemented and a con-
certed effort made to protect the worker. These actions
help assure personnel that their health and safety will be
protected now and in the future.
B. Weather
Adverse weather conditions are Important considerations 1n plan-
ning and conducting site operations. Hot or cold weather can
causa physical discomfort, loss of efficiency, and personal
injury. Of particular importance is heat stress resulting when
protective clothing decreases natural body ventilation. Heat
stress can occur even when temperature are moderate. One or more
of the following recommendations will help reduce heat stress:
- Provide plenty of liquids. To replace body fluids (water and
electrolytes) lost due to sweating, use a 0.1% salt water
solution, more heavily salted foods, or commercial mixes. The
commercial mixes may be preferable for those employees on a
low-sodium diet.
- Provide cooling devices to aid natural body ventilation.
These devices, however, add weight, and their use should be
balanced against worker efficiency. Long cotton underwear
act as a wick to help absorb moisture and protect the skin
from direct contact with heat-absorbing protective clothing.
It should be the minimum undergarment worn.
- Install mobile showers and/or hose-down facilities to reduce
body temperature and cool protective clothing.
3-5
-------
In extremely hot weather, conduct nonemergency response
operations in the early morning or evening.
Ensure that adequate shelter is available to protect personnel
against heat, cold, rain, snow, etc., which decrease physical
efficiency and increase the probability of accidents.
In hot weather, rotate workers wearing protective clothing.
C. Heat Stress Monitoring
For monitoring the body's recuperative ability to excess heat,
one or more of the following techniques should be used as a
screening mechanism. Monitoring of personnel wearing protective
clothing should commence when the ambient temperature is 70
degrees Fahrenheit or above. Frequency of monitoring should
increase as the ambient temperature increases or if slow recovery
rates are indicated. When temperatures exceed 80 degrees F
workers must be monitored for heat stress after every work period.
- Heart rate (HR) should be measured by the radial pulse for 30
seconds as early as possible in the resting period. The HR
at the beginning of the rest period should not exceed 110
beats per minute. If the HR is higher, the next work period
should be shortened by 10 minutes (or 33%), while the length
of the rest period stays the same. If the pulse rate is 100
beats per minute at the beginning of the next rest period,
the following work cycle should be shortened by 33%.
- Body temperature should be measured orally with a clinical
thermometer as early as possible in the resting period. Oral
temperature (OT) at the beginning of the rest period should
not exceed 99 degrees Fahrenheit. If it does, the next work
period should be shortened by 10 minutes (or 33%), while the
length of the rest period stays the same. However, if the' OT
exceeds 99.7 degrees Fahrenheit at the beginning of the next
period, the following work cycle should be further shortened
by 33%. OT should be measured again at the end of the rest
period to make sure that it has dropped below 99 degrees
Fahrenheit.
- Body water loss (BWL) due to sweating should be measured by
weighing the worker in the morning and in the evening. The
clotlTTng worn should be similar at both weighings; preferably
the worker should be nude. The scale should be accurate to
plus or minus 1/4 Ib. BWL should not exceed 1.5% of the
total body weight. If it does, workers should be instructed
to increase their daily intake of fluids by the weight lost.
3-6
-------
Ideally, body fluids should be maintained at a constant level
during the work day. This requires replacement of salt lost
in sweat as wel1.
Good hygienic standards must be maintained by frequent change of
clothing and daily showering. Clothing should be permitted to
dry during rest periods. Persons who notice skin problems should
immediately consult medical personnel.
D. Effects of Heat Stress
If the body's physiological processes fail to maintain a normal
body temperature because of excessive heat, a number of physical
reactions can occur ranging from mild (such as fatigue, irrita-
bility, anxiety, and decreased concentration, dexterity, or
movement) to fatal. Standard reference books should be consulted
for specific first aid treatment. Medical help must be obtained
for the more serious conditions.
Heat-related problems are:
- Heat rash: caused by continuous exposure to heat and humid air
and aggravated by chafing clothes. Decreases ability to
tolerate heat as well as being a nuisance.
- Heat cramps: caused by profuse perspiration with inadequate
fluid intake and chemical replacement (especially salts).
Signs: muscle spasm and pain in the extremities and abdomen.
- Heat exhaustion: caused by increased stress on various organs
to meetincreased demands to cool the body. Signs: shallow
breathing; pale, cool, moist skin; profuse sweating; dizziness
and lassitude.
- Heat stroke: the most severe form of heat stress. Body must
be cooledimmediately to prevent severe injury and/or death.
Signs: red, hot, dry skin; no perspiration; nausea; dizziness
and confusion; strong, rapid pulse; coma. Medical help must
be obtained immediately.
E. Effects of Cold Exposure
Persons working outdoors in temperatures at or below freezing may
be frostbitten. Extreme cold for a short time may cause severe
injury to exposed body surfaces, or result in profound generalized
cooling, causing death. Areas of the body which have high surface
area-to-volume ratio such as fingers, toes, and ears, are the
most susceptible.
3-7
-------
Two factors influence the development of a cold injury: ambient
temperature and the velocity of the wind. Wind chill is used to
describe the chilling effect of moving air in combination with
low temperature. For instance, 10 degrees Fahrenheit with a wind
of 15 miles" per hour (mph) is equivalent in chilling effect to
still air at -18 degrees Fahrenheit.
As a general rule, the greatest incremental increase in wind
chill occurs when a wind of 5 mph increases to 10 mph. Addi-
tionally, water conducts heat 240 times faster than air. Thus,
the body cools suddenly when chemical-protective equipment is
removed if the clothing underneath is perspiration soaked.
Local injury resulting from cold is included in the generic term
frostbite. There are several degrees of damage. Frostbite of
the extremities can be categorized into:
- Frost nip or incipient frostbite: characterized by suddenly
blanching or whitening of skin.
- Superficial frostbite: skin has a waxy or white appearance
and is firm to the touch, but tissue beneath is resilient.
- Deep frostbite: tissues are cold, pale, and solid; extremely
serious injury.
Systemic hypothermia is caused by exposure to freezing or rapidly
dropping temperature. Its symptoms are usually exhibited in five
stages: 1) shivering, 2) apathy, 1istlessness, sleepiness, and
(sometimes) rapid cooling of the body to less than 95 degrees
Fahrenheit, 3) unconsciousness, glassy stare, slow pulse, and
slow respiratory rate, 4) freezing of the extremities, and
finally, 5) death.
Standard reference books should be consulted for specific first
aids treatments. Medical help must be obtained for the more
serious conditions.
F. Indicators of Toxic Exposure Effects
- Observeable by others
-- changes in complexion, skin discoloration
— lack of coordination
— changes in demeanor
— excessive salivation, pupillary response
3-8
-------
changes In speech pattern
- Non-Observeable by others
— headaches
— dizziness
— tlurred vision
cramps
— irritation of eyes, skin, or respiratory tract
VII- SUMMARY
The health and safety of response personnel are major considerations
in all response operations. All site operation planning must incor-
porate an analysis of the hazards involved and procedures for pre-
venting or minimizing the risk to personnel. The Site Safety Plan
establishes the safety practices and procedures to be followed so
that the welfare and safety of workers are protected. The plan must
evaluate both the nature of the chemical compounds present and otlier
hazards that could affect response personnel.
3-9
-------
SITE ENTRY - SURVEY AND RECONNAISSANCE
3. INTRODUCTION
The team initially entering the site is to accomplish one or more
of the following objectives:
- Determine the hazards that exist or potentially exist affecting
public health, the environment, and response personnel.
- Verify existing information and/or obtain information about the
incident.
- Evaluate the need for prompt mitigation.
- Collect supplemental information to determine the safety require-
ments for personnel initially and subsequently entering the site.
Before the team enters the site, as much information as possible
should be collected, depending on the time available, concerning the
type of hazards, degree of hazard(s), and risks which may exist.
Based upon available information (shipping manifests, transportation
placards, existing records, container labels, etc.) or off-site
studies, the team assesses the hazards, determines the need to go on-
site, and identifies initial safety requirements.
II. PRELIMINARY ON-SITE EVALUATION
The initial on-site survey is to determine, on a preliminary basis,
hazardous or potentially hazardous conditions. The main effort is to
rapidly identify the immediate hazards that may affect the public,
response personnel, and the environment. Of major concern are the
real or potential dangers from, fire, explosion, airborne contam-
inants and to a lesser degree raiation and oxygen deficient atmos-
pheres.
A. Organic Vapors and Gases
If the type of organic substance involved in an incident is known
and the material is volatile or can become airborne, air measure-
ments for organics should be made with one or more appropriate,
properly calibrated survey instruments.
When the presence or types of organic vapors/gases are unknown,
instruments such as a photoionizer (HNU Systems*) and/or a por-
table gas chromatograpn (Foxboro Systems OVA*), operated in the
total readout mode, should be used to detect organic vapors.
*The use of any trade names does not imply their endorsement by
the U.S. Environmental Protection Agency.
4-1
-------
Until specific constituents can be identified, the readout indi-
cates total airborne substances to w^ch the instrument - s
responding. Identification of the individual vapor/gas consti-
tuents may permit the instruments to be calibrated to tnese
substances and used for more specific and accurate analysis.
Sufficient data should be obtained during the initial entry to
map or screen the site for various levels of organic vapors.
These gross measurements may be used on a preliminary basis to:
1) determine levels of personnel protection, 2) establish site
work zones, and 3} select candidate areas for more thorough
qualitative and quantitative studies.
Very high readings on the HNU or OVA may also indicate the dis-
placement of oxygen or the presence of combustible vapors.
B. Inorganic Vapors and Gases
The number of direct reading instruments with the capability to
detect and quantify nonspecific inorganic vapors and gases is
extremely limited. Presently, the HNU photoionizer has very
limited detection capability while the Foxboro OVA has none.
(See Appendix I for characteristics). If specific inorganics are
known or suspected to be present, measurements should be made
with appropriate instruments, if available. Colorimetric tubes
are only practical if substances present are known or can be
narrowed to a few.
C. Radiation
Although radiation monitoring is not necessary for all responses,
it should be incorporated in the initial survey where radioactive
materials may be present - for example, fires at warehouses or
hazardous material storage facilities, transportation incidents
involving unknown materials, or abandoned waste sites.
Normal background exposure-rate for gamma radiation is approx-
imately 0.01 to 0.02 milliroentgen per hour (mR/hr) on a gamma
survey instrument. Work can continue with elevated radiation-
exposure rates; however, if the exposure-rate increases to 3-5
times above gamma background, a qualified health physicist should
be consulted. At no time should work continue with an exposure
rate of 10 mR/hr or above without the advice of a health physicist.
EPA's Office of Air, Noise and Radiation has radiation specialists
in each Region, as well as at Headquarters, Montgomery, Alabama,
and Las Vegas, Nevada, to assist. The absence of gamma readings
above background should not be interpreted as the complete absence
of radioactivity. Radioactive materials emitting low-energy gam-
4-2
-------
ma, alpha, or beta radiation may be present, Out for a number of
reasons mav not ca'jse a resoonse o^ the instrumert. Unless
airborne, these radioactive materials should present minimal
hazard, but more thorough surveys should be conducted as site
operations continue to completely rule out the presence of any
radioactive material.
D. Oxygen Deficiency
Normal air contains about 20.5% by volume of oxygen. At or
below 19.5% oxygen air-supplied respiratory protective equipment
is needed. Oxygen measurements are of particular importance for
work in enclosed spaces, low-lying areas, or in the vicinity of
accidents that have produced heavier-than-air vapors which could
displace ambient air. These oxygen deficient areas are also prime
locations for taking further organic vapor and combustible gas
measurements, since the air has been displaced by other sub-
stances. Oxygen-enriched atmospheres increase the potential for
fires.
£. Combustible Gases
The presence or absence of combustible vapors or gases must be
determined. If readings approach or exceed 10% of the lower
explosive limit (LEL), extreme caution should be exercised in
continuing the investigation. If readings approach or exceed 25%
LEL, personnel should be withdrawn immediately. Before resuming
any on-site activities, project personnel in consultation with
experts in fire or explosion prevention must develop procedures
for continuing operations.
F. Visual Observations
While on-site', the initial entry team should make visual obser-
vations which would help in evaluating site hazards, for example,
dead fish or other animals; land features; wind direction; labels
on containers indicating explosive, flammable, toxic, or corrosive
materials; conditions conducive to splash or contact with uncon-
fined liquids, sludges, or solids; and other general conditions.
G. Direct-Reading Instruments
A variety of toxic air pollutants, (including organic and in-
organic vapors, gases, or particulates) can be produced at, for
example, abandoned waste sites; fires at chemical manufacturing,
storage, reprocessing, or formulating facilities; or fires invol-
ving pesticides. Direct-reading field instruments will not
detect or measure all of these substances. Thus, negative
readings should not be interpreted as the complete absence of
airborne toxic substances. Verification of negative results can
4-3
-------
only be done by collecting air samples and analyzing them in a
laboratory.
III. OTHER CONSIDERATIONS
A. Initial Surveys
In general, the initial entry is considered a relatively rapid
screening process for collecting preliminary data on site hazards.
The time needed to conduct the initial survey depends on the
urgency of the situation, type of incident, information needed,
size of site, availability of resources, and Level of Protection
required for initial entry personnel. Consequently, initial
surveys may need hours or days to complete and consist of more
than one entry.
B, Priority for Initial Entry Monitoring
Of immediate concern to initial entry personnel are atmospheric
conditions which could affect their immediate safety. These
conditions are airborne toxic substances, combustible gases or
vapors, lack of oxygen, and to a lesser extent, ionizing radia-
tion. Priorities for monitoring these potential hazards should
be established after a careful evaluation of conditions.
When the type of material involved in an incident is identified
and its release into the environment suspected or known, the
material's chemical/physical properties and the prevailing weather
conditions may help determine the order of monitoring. An unknown
substance or situation presents a more difficult monitoring
problem.
In general, for poorly-ventilated spaces - buildings, ship's
holds, boxcars, or bulk tanks - which must be entered, combustible
vapors/gases and oxygen-deficient atmospheres should be monitored
first with team members wearing, as a minimum, Level B protective
equipment (Levels of Protection are described in Part 5). Toxic
gases/vapors and radiation, unless known not to be present,
should be measured next.
For open, well-ventilated areas, combustible gases and oxygen
deficiently are lesser hazards, and require lower priority.
However, areas of lower elevation on-site (such as ditches and
gulleys) and downwind areas may have combustible gas mixtures, in
addition to toxic vapors or gases, and lack sufficient oxygen to
sustain life. Entry teams should approach and monitor whenever
possible from the upwind area.
4-4
-------
C. Periodic Monitoring
The monitoring surveys made during the initial site entry phase
are for a preliminary evaluation of atmospheric hazards. In some
situations, the information obtained may be sufficient to preclude
additional monitoring - for example, a chlorine tank determined
to be releasing no chlorine. Materials detected during the
initial site survey call for a more comprehensive evaluation of
hazards and analyses for specific components. A program must be
established for monitoring, sampling, and evaluating hazards for
the duration of site operations. Since site activities and
weather conditions change, a continuous program to monitor atmos-
pheric changes must be implemented utilizing a combination of
stationary sampling equipment, personal monitoring devices, and
periodic area monitoring with direct-reading instruments.
D. Off-Site Monitoring and Sampling
Whenever possible, atmospheric hazards in the areas adjacent to
the on-site zone should be monitored with direct-reading instru-
ments, and air samples should be taken before the initial entry
for on-site investigations. Negative instrument readings off-
site should not be construed as definite indications of on-site
conditions, but only another piece of information to assist in
the preliminary evaluation.
E. Monitoring Instruments
It is imperative that personnel using monitoring instruments be
thoroughly familiar with their use, limitations, and operating
characteristics. All instruments have inherent constraints in
their ability to detect and/or quantify the hazards for which
they were designed. Unless trained personnel use instruments and
assess data readout, air hazards can be grossly misinterpreted,
endangering the health and safety of response personnel. In
addition, only instruments approved for use in hazardous locations
should be used, unless combustible gases or vapors are absent.
F. Ambient Atmospheric Concentrations
Any indication of atmospheric hazards - toxic substances, combus-
tible gases, lack of oxygen, and radiation - should be viewed as a
sign to proceed with care and deliberation. Readings indicating
nonexplosive atmospheres, low concentrations of toxic substances,
or other conditions may increase or decrease suddenly, changing
the associated risks. Extreme caution should be exercised in
continuing surveys when any atmospheric hazards are indicated.
4-5
-------
TABLE 4-1
ATMOSPHERIC HAZARD GUIDELINES
Monitoring Equipment
Hazard
Ambient Level
Action
Combustible gas indicator Explosive
atmosphere
Oxygen concentration meter Oxygen
Radiation survey meter
Ionizing
Radiation
< 10% LEL
10%-25%
Continue investigation
with cautions.
Continue on-site
monitoring with extreme
caution as higher levels
are encountered.
> 251 LEL
< 19.55
Explosion
from area
hazard; withdraw
immediately.
Monitor wearing SCBA.
NOTE: Combustible gas
readings are not val id
in atmospheres with
< 19.5% oxygen.
19.5%-25% Continue investigation with
caution. SCBA not needed,
based on oxygen content
only.
.> 25.0% Discontinue inspection;
fire hazard potential.
Consult specialist.
< 1 mR/hr Continue investigation.
If radiation is detected
above background levels,
this signifies the presence
of possible radiation sources;
at this level, more thorough
monitoring is advisable.
Consult with a
health physicist.
> 10 mR/hr Potential radiation hazard;
evacuate site. Continue moni-
toring only upon the advice
of a health physicist.
4-6
-------
ANNEX 1
LEVEL A DECONTAMINATION
A. EQUIPMENT WORN
The full decontamination procedure outlined is for workers wearing
Level A protection (with taped joints between gloves, boots, and
suit) consisting of:
- Fully encapsulating suit,
- Self-contained breathing apparatus.
- Hard hat (optional).
- Chemical-resistant, steel toe and shank boots.
- Boot covers.
Inner and outer gloves.
B. PROCEDURE FOR FULL DECONTAMINATION
Station 1: Segregated Equipment Drop
Deposit equipment used on-s.ite (tools, sampling devices and containers,
monitoring instruments, radios, clipboards, etc.) on plastic drop
cloths or in different containers with plastic liners. Each will be
contaminated to a different degree. Segregation at the drop reduces
the probability of cross-contamination.
Equipment: various size containers
plastic liners
plastic drop cloths
Station 2: Boot Cover and Glove Wash
Scrub outer boot covers and gloves with decon solution or detergent/
water.
Equipment: container (20-30 gallons)
decon solution
or
detergent water
2-3 long-handle, soft-bristle scrub brushes
Al-1
-------
Station 3: Boot Cover and Glove Rinse
Rinse off decon solution from Station 2 using copious amounts of
water. Repeat as many times as necessary.
Equipment: container (30-50 gallons)
or
high-pressure spray unit
water
2-3 long-handle, soft-bristle scrub brushes
Station 4: Tape Removal
Remove tape around boots and gloves and deposit in container with
plastic liner.
Equipment: container (20-30 gallons)
plastic liners
Station 5: Boot Cover Removal
Remove boot covers and deposit in container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
Station 6: Outer Glove Removal
Remove outer gloves and deposit in container with plastic liner.
Equipment: container (20-30 gallons)
plastic liners
Station 7: Suit/Safety Boot Wash
Thoroughly wash fully encapsulating suit and boots. Scrub suit
and boots with long-handle, soft-bristle scrub brush and copious
amounts of decon solution or detergent/water. Repeat as many
times as necessary.
Equipment: container (30-50 gallons)
— decon solution
or
detergent/water
2-3 long-handle, soft-bristle scrub brushes
Al-2
-------
Station 8: Suit/Safety Boot Rinse
Rinse off decon solution or detergent/water using copious amounts
of water. Repeat as many times as necessary.
Equipment: container (30-50 gallons)
or
high-pressure spray unit
water
2-3 long handle, soft-bristle scrub brushes
Station 9: Tank Change
If worker leaves Exclusion Zone to change air tank, this is the
last step in the decontamination procedure. Worker's air tank is
exchanged, new outer gloves and boots covers donned, and joints
taped. Worker then returns to duty.
Equipment: air tanks
tape
boot covers
gloves
Station 10: Safety Boot Removal
Remove safety boots and deposit in container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
boot jack
Station 11: Fully Encapsulating Suit and Hard Hat Removal
With assistance of helper, remove fully encapsulating suit (and
hard hat). Hang suits on rack or lay out on drop cloths.
Equipment: rack
drop cloths
bench or stool
Station 12: SC8A Backpack Removal
While still wearing facepiece, remove backpack and place on table.
Disconnect hose from regulator valve and proceed to next station.
Equipment: table
Al-3
-------
Station 13: Inner Glove Wash
Wash with decon solution or detergent/water that will not harm
skin. Repeat as many times as necessary.
Equipment: basin or bucket
decon solution
or
detergent/water
small table
Station 14: Inner Glove Rinse
Rinse with water. Repeat as many times as necessary.
Equipment: water basin
basin or bucket
small table
Station 15: Facepiece Removal
Remove facepiece. Deposit in container with plastic liner. Avoid
touching face with fingers.
Equipment: container (30-50 gallons)
plastic liners
Station 16: Inner Glove Removal
Remove inner gloves and deposit in container with plastic liner.
Equipment: container (20-30 gallons)
plastic liners
Station 17: Inner Clothing Removal
Remove clothing soaked with perspiration. Place in container with
plastic liner. Inner clothing should be removed as soon as possible
since there is a possibility that small amounts of contaminants might
have been transferred in removing fully encapsulating suit.
Equipment: container (30-50 gallons)
plastic liners
Station 18: Field Wash
Shower if highly toxic, skin-corrosive or skin-absorbable materials
are known or suspected to be present. Wash hands and face If shower
is not available.
Al-4
-------
equipment:
water
soap
small table
basin or bucket
field showers
towels
Station 19: Redress
Put on clean clothes. A dressing trailer is needed in inclement weather.
Equipment: tables
chairs
lockers
clothes
C. FULL DECONTAMINATION (SIT. 1) AND THREE MODIFICATIONS
s
I
T
1
2
3
4
STATION NUMBER
1
X
X
X
X
2
X
X
3
X
X
4
X
X
5
X
X
6
X
X
1
7
X
X
X
X
8
X
X
X
X
9
X
X
10
X
X
11
X
X
12
X
X
13
X
14
X
15
X
X
16
X
X
17
X
X
18
X
X
19
X
Situation 1; The individual entering the Contamination Reduction
Corridor is observed to be grossly contaminated or extremely toxic
substances are known or suspected to be present.
Situation 2: Same as Situation 1 except individual needs new air tank
and will .return to Exclusion Zone.
Al-5
-------
Situation 3: Individual entering the CRC is expected to be minimally
contaminated. Extremely toxic or skin-corrosive materials are not
present. No outer gloves or boot covers are worn. Inner gloves are
not contaminated.
Situation 4: Same as Situation 3 except individual needs new air tank
and wiill return to Exclusion Zone.
EXCLUSION
ZONE
OUTER GLOVE
REMOVAL
TANK CHANGE
CONTAMINATION
REDUCTION
ZONE
BOOT coven
4
GLOVE WASH
TAPE
REMOVAL
•OOT coven
REMOVAL
SOOT COVER
GLOVE RINSE
SUIT/SA*€TY SOOT
WASH
SUIT/SAFETY SOOT
RINSE
*AFETY SOOT
REMOVAL
FULLY ENCAPSULATING SUIT
AND HARD HAT REMOVAL
SC8A BACKPACK
REMOVAL
INNER GLOVE
WASH
INNER GLOVE
RINSC
FACE PIECZ
REMOVAL
INNER GLOVE
REMOVAL
INNER CLOTHING
REMOVAL
SEGREGATED
EQUIPMENT
DROP
— HOTLINE —• «
DECONTAMINATION LAYOUT
L£VEL A PROTECTION
FIGURE A1-1
CONTAMINATION
CONTROL LINE
FIELD
WASH
SUPPORT
ZONE
Al-6
-------
ANNEX 2
LEVEL B DE::NTAMIN-T:ON
A. EQUIPMENT WORN
The full decent amination procedure outlined is for workers wearing
Level B protection (with taped joints between gloves, boot, and suit)
consisting of:
- One-piece, hooded, chemical-resistant splash suit.
Self-contained breathing apparatus.
- Hard hat.
- Chemical-resistant, steel toe and shank boots.
- Boot covers
- Inner and outer gloves.
B. PROCEDURE FOR FULL DECONTAMINATION
Station 1: Segregated Equipment Drop
Deposit equipment used on-site (tools, sampling devices and containers,
monitoring instruments, radios, clipboards, etc.) on plastic drop
cloths or in different containers with plastic liners. Each will be
contaminated to a different degree. Segregation at the drop reduces
the probability of cross-contamination.
Equipment: various size containers
plastic liners
plastic drop cloths
Station 2: Boot Cover and Glove Wash
Scrub outer boot covers and gloves with decon solution or detergent/
water.
Equipment: container (20-30 gallons)
decon solution
or
detergent water
2-3 long-handle, soft-bristle scrub brushes
A2-1
-------
Station 3: Boot Cover and Glove Rinse
Rinse off decon solution from Station 2 using copious amounts of
water. Repeat as many times as necessary.
Equipment: container (30-50 gallons)
or
high-pressure spray unit
water
2-3 long-handle, soft-bristle scrub brushes
Station 4: Tape Removal
Remove tape around boots and gloves and deposit in container with
plastic liner.
Equipment: container (20-30 gallons)
plastic liners
Station S: Boot Cover Removal
Remove boot covers and deposit in container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
Station 6: Outer Glove Removal
Remove outer gloves and deposit in container with plastic liner.
Equipment: container (20-30 gallons
plastic liners
Station 7: Suit/Safety Boot Wash
Thoroughly wash chemical-resistant splash suit, SCBA, gloves, and
safety boots. Scrub with long-handle, soft-bristle scrub brush
and copious amounts of decon solution or detergent/water. Wrap
SCBA regulator (if belt-mounted type) with plastic to keep out
water. Wash backpack assembly with sponges or cloths.
Equipment: container (30-50 gallons)
decon solution
or
detergent/water
2-3 long-handle, soft-bristle scrub brushes
small buckets
sponges or cloths
A2-2
-------
Stan or. 8: Suit/SCBA/Boot/Glove Rinse
Rinse off decon solution or detergent/water using copious amounts
of water. Repeat as many times as necessary.
Equipment; container (30-50 gallons)
or
nigh-pressure spray unit
water
small buckets
2-3 long-handle, soft-bristle scrub brushes
sponges or cloths
Station 9: Tank Change
If worker leaves Exclusion Zone to change air tank, this is the last
step in the decontamination procedure. Worker's air tank is
exchanged, new outer gloves and boots covers donned, and joints
taped. Worker returns to duty.
Equipment: air tanks
tape
boot covers
gloves
Station 10: Safety Boot Removal
Remove safety boots and deposit in container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
„. boot jack
Station 11: SCBA Backpack Removal
While still wearing facepiece, remove backpack and place on table.
Disconnect hose from regulator valve and proceed to next station.
Equipment: table
Station 12: Splash Suit Removal
With assistance of helper, remove splash suit. Deposit in container
with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
A2-3
-------
Station 13: Inner Glove Wash
Wash inner gloves with decon solution or detergent/water that will
not harm skin. Repeat as many times as necessary.
Equipment: decon solution
or
detergent/water
basin or bucket
small table
Station 14: Inner Glove Rinse
Rinse inner gloves with water. Repeat as many times as necessary.
Equipment: water
basin or bucket
small table
Station 15: Facepiece Removal
Remove facepiece. Avoid touching face with gloves. Deposit in
container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
Station 16: Inner Glove Removal
Remove inner gloves and deposit in container with plastic liner.
Equipment: container (20-30 gallons)-
plastic liners
Station 17: Inner Clothing Removal
Remove clothing soaked with perspiration. Place in container with
plastic liner. Do not wear inner clothing off-site since there is
a possibility small amounts of contaminants might have been
transferred in removing fully encapsulating suit.
Equipment: container (30-50 gallons)
plastic 1iners
Station 18: Field Wash
Shower if highly toxic, skin-corrosive, or skin-absorbable materials
are known or suspected to be present. Wash hands and face if shower
is not available.
A2-4
-------
Equipment: water
soap
sma1,1 tables
basins or buckets
field showers
Station 19: Redress
Put on clean clothes. A dressing trailer is needed in inclement
weather.
Equipment: tables
chairs
lockers
clothes
C. FULL DECONTAMINATION (SIT. 1) AND THREE MODIFICATIONS
s
I
T
1
2
3
4
STATION NUMBER
1
X
X
X
X
2
X
X
3
X
X
4
X
X
5
X
X
6
X
X
7
X
X
X
X
8
X
X
X
X
9
X
X
10
X
X
11
X
X
12
X
X
13
X
14
X
15
X
X
16
X
X
17
X
X
18
X
X
19
X
X
Situation 1: The individual entering the Contamination Reduction
Corridor is observed to be grossly contaminated or extremely toxic
substances are known or suspected to be present.
Situation 2: Same as Situation 1 except individual needs new air tank
and wlU return to Exclusion Zone.
A2-5
-------
Situation 3: Individual entering the CRC 1s expected to be minimally
contaminated. Extremely toxic or skin-corrosive materials are not
present No outer gloves or boot covers are worn. Inner gloves are
not contaminated.
Situation 4: Same as Situation 3 except
and wi 11 return to Exclusion Zone.
individual needs new air tank
OUTER GLOVE
REMOVAL
EXCLUSION
ZONE
TAP<
REMOVAL
SOOT COVER
A
GLOVE WASH
TANK CHANGE
SUIT/SAFETY 8OOT
WASH
suiT/scsA/aoor/CLOve
ftlNSC
10 i
SAfETY 8OOT
REMOVAL
11
CONTAMINATION
REDUCTION
ZONE
13]
JC1A 8ACXPACX
REMOVAL
SPLASH SUIT
REMOVAL
INNEfl GLOVE
WASH
DECONTAMINATION LAYOUT
L£VEU 8 PROTECTION
FIGUflE A2-1
14 I
INNER GLOVE
RINSE
1$ I
FAC£ P1EC2
REMOVAL
INNER QLOVC
REMOVAL
INNER CLOTHINO
REMOVAL
CONTAMINATION
" CONTROL UNE
WA«H
REOREU
SUPPORT
ZONE
A2-6
-------
ANNEX 3
LEVEL C DECONTAMINATION
A. EQUIPMENT WORN
The full decontamination procedure outlined is for workers wearing
Level C protection (with taped joints between gloves, boots, and
suit) consisting of:
- One-piece, hooded, chemical-resistant splash suit.
- Canister equipped, full-face mask.
- Hard hat.
- Chemical-resistant, steel toe and shank boots.-
- Boot covers.
- Inner and outer gloves.
B. PROCEDURE FOR FULL DECONTAMINATION
Station 1: Segregated Equipment Drop
Deposit equipment used on-site (tools, sampling devices and containers,
monitoring instruments, radios, clipboards, etc.) on plastic drop
cloths or in different containers with plastic liners. Each will be
contaminated to a different degree. Segregation at the drop reduces
the probability of cross-contamination.
Equipment: various size containers
plastic liners
plastic drop cloths
Station 2: Boot Cover and Glove Wash
Scrub outer boot covers and gloves with decon solution or detergent/
water.
i
Equipment: container (20-30 gallons)
decon solution
or
detergent water
2-3 long-handle, soft-bristle scrub brushes
A3-1
-------
Station 3: Boot Cover and Glove Rinse
Rinse off decon solution from Station 2 using copious amounts of
water. Repeat as many times as necessary.
Equipment: container (30-50 gallons)
or
high-pressure spray unit
water
2-3 long-handle, soft bristle scrub brushes
Station 4: Tape Removal
Remove tape around boots and gloves and deposit in container with
plastic liner.
Equipment: container (20-30 gallons)
plastic liners
Station 5: Boot Cover Removal
Remove boot covers and deposit in container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
Station 6: Outer Glove Removal
Remove outer gloves and deposit in container with plastic liner.
Equipment: container (20-30 gallons)
plastic liners
Station 7: Suit/Safety Boot Wash
Thoroughly wash splash suit and safety boots. Scrub with long-
handle, soft-bristle scrub brush and copious amounts of decon
solution or detergent/water. Repeat as many times as necessary.
Equipment: container (30-50 gallons)
decon solution
or
detergent/water
2-3 long-handle, soft-bristle scrub brushes
Station 8: Suit/Safety Boot Rinse
A3-2
-------
Rinse off deccm solution or detergent/water using copious amounts
of water. Repeat as many times as necessary.
Equipment: container (30-50 gallons)
or
high-pressure spray unit
water
2-3 long-handle, soft-bristle scrub brushes
Station 9: Canister or Mask Change
If worker leaves Exclusion Zone to change canister (or mask), this
is the last step in the decontamination procedure. Worker's canister
is exchanged, new outer gloves and boots covers donned, and joints
taped. Worker returns to duty.
Equipment: canister (or mask)
tape
boot covers
gloves
Station 10: Safety Boot Removal
Remove safety boots and deposit in container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
boot jack
Station 11: Splash Suit Removal
With assistance of helper, remove splash suit. Deposit in container
with plastic liner.
Equipment: container (30-50 gallons)
bench or stool
liner
Station 12: Inner Glove Wash
Wash inner gloves with decon solution or detergent/water that will
not harm skin. Repeat as many times as necessary.
Equipment: decon solution
or
detergent/water
basin or bucket
A3-3
-------
Station 13: Inner Glove Rinse
Rinse inner gloves with water. Repeat as many times as necessary.
Equipment: water
basin or bucket
small table
Station 14: Facepiece Removal
Remove facepiece. Avoid touching face with gloves. Deposit
facepiece in container with plastic liner.
Equipment: container (30-50 gallons)
plastic liners
Station 15: Inner Glove Removal
Remove inner gloves and deposit in container with plastic liner.
Equipment: container (20-30 gallons)
plastic liners
Station 16: Inner Clothing Removal
Remove clothing soaked with perspiration. Place in container with
plastic liner. Do not wear inner clothing off-site since there is
a possibility small amounts of contaminants might have been
transferred in removing splash suite.
Equipment: container (30-50 gallons)
plastic liners
Station 17: Field Wash
Shower if highly toxic, skin-corrosive or skin-absorbable materials
are known or suspected to be present. Wash hands and face if shower
is not available.
Equipment: water
soap
tables
wash basins/buckets
— field showers
Station 18: Redress
Put on clean clothes. A dressing trailer is needed in inclement weather.
A3-4
-------
Equi prnent:
tables
chairs
lockers
clothes
C. FULL DECONTAMINATION (SIT. 1) AND THREE MODIFICATIONS
s
I
T
1
2
3
4
STATION NUMBER
1
X
X
X
X
2
X
X
3
X
X
4
X
X
5
X
X
6
X
X
7
X
X
X
X
8
X
X
X
X
9
X
X
X
10
X
X
11
X
X
12
X
13
X
14
X
X
15
X
X
16
X
X
17
X
X
18
X
Situation 1: The individual entering the Contamination Reduction Corridor
is observed to be grossly contaminated or extremely skin corrosive substances
are known or suspected to be present.
Situation 2: Same as Situation 1 except individual needs new canister or
mask and will return to Exclusion Zone.
Situation 3: Individual entering the CRC is expected to be minimally
contaminated. Extremely skin-corrosive materials are not present. No
outer gloves or boot covers are worn. Inner gloves are not contaminated.
Situation 4: Same as Situation 3 except individual needs new canister or
mask -and will return to Exclusion Zone.
A3-5
-------
EXCLUSION
ZONE
OUTER OLOV*
REMOVAL
REMOVAL
•OOT COVtJI
1,
QLOVC WASH
CANISTER OH
MASKCHANOi
•OOT COVW
ACMOVAL
7']
BOOT COVM-4
OLOVIKINSC
BOOT
WAXM
KINM
IOCT
•«-HOTUNg-«-
MCMOVAt.
CONTAMINATION
REDUCTION
ZONE
121
13
SPLASH SUIT
HCMOVAC
INNUI auovt
WASH
INNCT GUOVt
RINSC
Of CONTAMINATION LAYOUT
L£VIL C
PIOUM A>1
1*1
ptecc
NCMOVAL
,15]
INNCR GLOVt
NCMOVAt.
INNM CLOTHINa
MCMOVAL
WASH
I IT
NCOKKS*
., CONTAMINATION
CONTROL UN*
SUPPORT
ZONE
A3-6
-------
ANNEX 4
LEVEL A DECONTAMINATION, MINIMUM LAYOUT
A. EQUIPMENT WORN
The decontamination procedure outlined Is for workers wearing Level A
protection (with taped joints oetween gloves, boots, and suit) consisting
of:
- Fully encapsulating suit with integral boots and gloves.
- Self-contained breathing apparatus.
- Hard hat (optional).
- Chemical-resistant, steel toe and shank boots.
- Boot covers.
Inner and outer gloves.
B, PROCEDURE FOR FULL DECONTAMINATION
Station 1; Segregated Equipment Drop
Deposit equipment used on-site (tools, sampling devices and containers,
monitoring instruments, radios, clipboards, etc.) on plastic drop
cloths or in different containers with plastic liners. Each will be
contaminated to a different degree. Segregation at the drop reduces
the probability of cross-contamination.
Equipment: various size containers
plastic liners
plastic drop clothes
Station 2: Outer Garment, Boots, and Gloves Wash and Rinse
Scrub outer boots, outer gloves, and fully-encapsulating suit with
deconjjiplution or detergent water. Rinse off using copious amounts
of water.
Equipment: containers (30-50 gallons)
decon solution
or
detergent water
A4-1
-------
n nse water
2-3 long-handle, soft-bristle scrub brushes
Station 3: Outer Boot and Glove Removal
Remove outer boots and gloves. Deposit in container with plastic
1 iner.
Equipment: container (30-50 gallons)
plastic liners
bench or stool
Station 4: Tank Change
If worker leaves Exclusion Zone to change air tank, this is the last
step in the decontamination procedure. Worker's air tank is exchanged,
new outer gloves and boot covers donned, joints taped, and worker
returns to duty.
Equipment: ai r tanks
tape
boot covers
gloves
Station 5: Boot, Gloves, and Outer Garment Removal
Boots, fully-encapsulating suit, and inner gloves removed and deposited
in separate containers lined with plastic.
Equipment: containers (30-50 gallons)
plastic liners
bench or stool
Station 6: SCBA Removal
SCBA backpack and facepiece is removed. Hands and face are thoroughly
washed. SCBA deposited on.plastic sheets.
Equipment: plastic sheets
basin or bucket
soap and towels
— bench
Station 7: Field Wash
Thoroughly wash hands and face. Shower as soon as possible.
A4-2
-------
EXCLUSION
ZONE
TANK
CHANGE
0
SEGREGATED EQUIPMENT
OftOP
••-HOTLINE-«-
OUTER GARMENT, SOOTS. ANO
GLOVES WASH ANO RINSE
CONTAMINATION
REDUCTION
ZONE
OUTER SOOT ANO
GLOVE REMOVAL
SOOTS. GLOVES. ANO
OUTER GARMENT
REMOVAL
MINIMUM
DECONTAMINATION LAYOUT
LEVEL A PROTECTION
FIGURE .
SC8A REMOVAL
CONTAMINATION
CONTROL LINE
6
F1EL3 WASH
SUPPORT
ZONE
A4-4
-------
PART 3
AIR SURVEILLANCE
I. INTRODUCTION
Accidents involving hazardous materials or remedial actions at aban-
doned waste sites can release a variety of substances Into the air.
Chemical fires, transportation accidents, open or leaking containers,
wind-blown dust, and site cleanup activities produce emissions which
can rapidly affect the health and safety of response workers and the
public. Hazardous atmospheres can involve:
- Flammable or explosive vapors, gases, and aerosols (explosive
atmosphere).
- Displacement of breathable air (oxygen-deficient atmosphere).
- Radioactive materials (radioactive environment).
- Toxic vapors, gases, and aerosols (toxic atmosphere).
The presence of one or more of these hazards determines subsequent
actions to protect people or the environment, operations to mitigate
the incident, and safety considerations for response workers.
Airborne hazards can be predicted if the substance involved, its
chemical and physical properties, and weather conditions are known.
But air surveillance is necessary to confirm predictions, to identify
or measure contaminants, or to detect unknown air pollutants.
This part provides guidance primarily on longer-term air sampling for
toxic substances. Information is given in Part 4, Initial Site Entry-
Survey and Reconnaissance, regarding initial determination of airborne
hazards.
II. OBJECTIVE OF AIR SURVEILLANCE
Air surveillance consists of air monitoring (using direct-reading
instruments capable of providing real-time indications of air
contaminants) and air sampling (collecting air on an appropriate
media or in a suitable sampling container followed by analysis).
The objective of air surveillance during response is to determine the
type of chemical compound (and associated hazard) and quantity of
airborne contaminants on-site and off-site and changes in air contami-
nants that occur over the lifetime of the incident.
8-1
-------
The data obtained are used to help establish criteria for worker
safety, document potential exposures, determine protective measures
for the public, evaluate the environmental impact of the incident,
and determine mitigation activities. To accomplish this requires
establishing an effective air surveillance program, tailored to meet
the conditions generated by each incident.
III. TYPES OF INCIDENTS
As part of initial hazard evaluation, direct-reading instruments
(DRIs), visible indicators (signs, labels, placards, type of con-
tainer, etc.). and other Information (manifests, consists, inven-
tories, Agency records, etc.) are used to evaluate the presence or
potential for air contaminant release. Limited air sampling may also
be conducted If time is available. Based on an assessment of this
preliminary information, a more comprehensive air surveillance
strategy is developed and implemented.
Two general types of incidents are encountered:
- Environmental emergencies, including chemical fires, spills, or
other releasesof hazardous materials which occur over a rela-
tively short period of time. Since contaminants may be released
rapidly, there may be no time for air surveillance. In incidents
where the released material can be quickly identified (and suffi-
cient time is available), direct-reading, hand-held monitoring
instruments can be used to provide information on some types of
hazards. Air sampling generally is limited unless the release
continues long enough for appropriate equipment to be brought in.
- Longer-term cleanup, including planned removals and remedial
actions atabandoned waste sites as well as restoration after
emergency problems have been controlled. During this period,
especially at waste sites, workers and the public may be exposed
to a wide variety of airborne materials over a much longer period
of time. Since cleanup activities require more time (and planning)
to accomplish, appropriate equipment for air monitoring and samp-
ling can be secured, and an air surveillance program established.
IV. GENERAL SURVEILLANCE METHODS
During site operations, data are needed about air contaminants and any
changes that may occur. Surveillance for vapors, gases, and parti-
culates is done using DRIs and air sampling systems. DRIs can be
used to detect many organics and a few inorganics and provide approxi-
mate total concentrations. If specific organics (and inorganics)
have been identified, then DRIs, calibrated to those materials,
can be used for more accurate on-site assessment. In many instances
8-2
-------
however, only air sampling (and laooratory analysis) can be used for
detection and quantification.
The most accurate method for evaluating any air contaminant is to
collect samples and analyze them at a reliable laboratory. Although
accurate, this method has two disadvantages: cost and the time re-
quired to obtain results. Analyzing large numbers of samples in
laboratories is very expensive, especially if results are wanted
quickly. On-site laboratories tend to reduce the turn-around time,
but unless they can analyze other types of samples, they also are
costly. In emergencies, time is often not available for laboratory
analysis of samples either on-site or off-site.
To obtain air monitoring data rapidly at the site, instruments uti-
lizing flame ionization detectors (FIDs) photoionization detectors
(PIDs) and other similar instruments can be used. These may be used
as survey instruments (total concentration mode) or operated as gas
chromatographs (gas chromatograph mode). As gas chromatographs,
these instruments can provide real-time, qualitative/quantative data
when calibrated with standards of known air contaminants. Combined
with selective laboratory analysis of samples, they provide a tool
for evaluating airborne organic hazards on a realtime basis, at a
lower cost than analyzing all samples in a laboratory. An example of
an air surveillance program used by the U.S. Environmental Protection
Agency's Environmental Response Team is contained in Annex 5.
V. AIR SAMPLING
For more complete information about air contaminants, measurements
obtained with DRIS must be supplemented by collecting and analyzing
air samples. To assess air contaminants more thoroughly, air sampling
devices equipped with appropriate collection media are placed at var-
ious locations throughout the area. These samples provide air quality
information for the period of time they operate, and can indicate con-
taminant types and concentrations over the lifetime of site operations.
As data are obtained (from the analysis of samples, DRIs, knowledge
about materials involved, site operations, and potential for airborne
toxic hazards), adjustments are made in the type of samples, number
of samples collected, frequency of sampling, and analysis required.
In addition to air samplers, area sampling stations may also include
DBls equipped with recorders and operated as continuous air monitors.
Area sampling stations are located in various places including:
- Upwind - Because many hazardous incidents occur near industries or
highways that generate air pollutants, samples must be taken upwind
of the site to establish background levels of air contaminants,
- Support zone - Samples must be taken near the command post or other
support facilities to ensure that they are in fact located in a
clean area, and that the area remains clean throughout operations
at the site.
8-3
-------
- Contamination reduction zone - Air samples should be collected
along the decontamination line to ensure that decontamination
workers are properly protected and that on-site workers are not
removing their protective gear in a contaminated area.
- Exclusion zone - The exclusion zone presents the greatest risk of
exposure to chemicals and requires the most air sampling. The
location of sampling stations should be based upon hot-spots
detected by DRIs, types of substance present, and potential for
airborne contaminants. The data from these stations, in con-
junction with intermittent walk-around surveys with DRIs, are used
to verify the selection of proper levels of worker protection and
exclusion zone boundaries, as well as to provide a continual
record of air contaminants.
- Downwind - One or more sampling stations are located downwind from
the site to indicate if any air contaminants are leaving the site.
If there are indications of airborne hazards in populated areas,
additional samplers should be placed downwind.
VI. MEDIA FOR CO! LUTING AIR SAMPLES
Hazardous material incidents, especially abandoned waste sites,
involve thousands of potentially dangerous substances - gases, vapors,
and aerosols that could become airborne. A variety of media - liquids
and solids - are used to collect these substances. Sampling systems
typically include a calibrated air sampling pump which draws air into
selected collection media. Some of the most common types of samples,
and the collection media used for them are:
~ Organic vapors - Activated carbon is an excellent adsorbent for
most organic vapors. However, other solid adsorbents (such as
Tenax, silica gel, and Florisil) are routinely used to sample
specific organic compounds or classes of compounds that do not
adsorb or desorb well on activated carbon. To avoid stocking a
large number of sorbents for all substances anticipated, a smaller
number chosen for collecting the widest range of materials or for
substances known to be present generally are used. The vapors are
collected using an industrial hygiene personal sampling pump with
either one sampling port or a manifold capable of simultaneously
collecting samples on several sorbent tubes, for example, a mani-
folcTwith four sorbent tubes (or as individual pumps with varying
flow rates). The tubes might contain:
— Activated carbon to collect vapors of materials with a boiling
point above 0 degrees centigrade. These materials include
most odorous organic substances, such as solvent vapors.
— A porous polymer such as Tenax or Chromosorb to collect sub-
stances (such as high-molecular-weight hydrocarbons, organo-
8-4
-------
phosphorous compounds, and the vapors of certain pesticides)
that adsorb poorly onto activated carbon. Some of these porc_s
polymers also adsorb organic materials at low ambient tempera-
tures more efficiently than carbon.
A polar sorbent such as silica gel to collect organic vapors
(aromatic amines, for example) that exhibit a relatively high
dipole moment.
-- Another specialty adsorbent selected for the specific site.
For example, a Florisil tube could be used if polychlorinated
biphenyls are expected.
- Inorganic gases - The inorganic gases present at an incident would
primarily be polar compounds such as the haloacid gases. They can
be adsorbed onto silica gel tubes and analyzed by ion chromato-
graphy. Impingers filled with selected liquid reagents can also
be used.
- Aerosols - Aerosols (solid or liquid particulates) that may be en-
countered at an incident include contaminated and noncontaminated
soil particles, heavy-metal particulates, pesticide dusts, and
droplets of organic or inorganic liquids. An effective method for
sampling these materials is to collect them on a particulate
filter such as a glass fiber or membrane type. A backup impinger
filled with a selected absorbing solution may also be necessary.
Colorimetric detector tubes can also be used with a sampling pump
when monitoring for some-, specific compounds. Passive organic vapor
monitors can be substituted for the active system described if passive
monitors are available for the types of materials suspected to be
present at a given site.
The National Institute for Occupational Safety and Health's (NIOSH)
Manual of Analytical Methods, Volumes 1-7, contains acceptable
methods forcollecting and analyzing air samples for a variety of
chemical substances. Consult it for specific procedures.
VII. COLLECTION AND ANALYSIS
Samples are analyzed to determine types and quantities of substances
present. The following provides additional guidance on sample col-
lection and analysis.
- Aerosols
Samples for aerosols should be taken at a relatively high flow rate
(generally about 2 liters/minute) using a standard industrial
hygiene pump and filter assembly. To collect total particulates,
8-5
-------
a membrane filter having a 0.8 micrometer pore size is common.
The sample can be weighed to determine total particulates, then
analyzed destructively or non-destructively for metals. If the
metals analysis is done nondestructively or if the filter is
sectioned, additional analyses (for example, organics, inorganics,
and optical particle sizing) can be performed.
- Sorbent Samples
The sorbent material chosen, the amount used, and sample volume
will vary according to the types and concentrations of substances
anticipated at a particular site. Polar sorbent material such
as silica gel will collect polar substances which are not adsorbed
well onto activated carbon and some of the porous polymers. The
silica gel sample can be split and analyzed for the haloacid gases
and aromatic amines.
Activated carbon and porous polymers will collect a wide range of
compounds. Exhaustive analysis to identify and quantify all the
collected species is prohibitively expensive at any laboratory and
technically difficult for a field laboratory. Therefore, samples
should be analyzed for principal hazardous constituents (PHCs).
The selection of PHCs should be based upon the types of materials
anticipated at a given site, from generator's records, and from
information collected during the initial site survey. To aid in
the selection of PHCs, a sample could be collected on activated
carbon or porous polymer during the initial site survey and ex-
haustively analyzed off-site to identify the major peaks within
selected categories. This one thorough analysis, along with what
is already known about a particular site, could provide enough
information to select PHCs. Standards of PHCs could then ' be
prepared and used to calibrate instruments used for field analysis
of samples. Subsequent, routine off-site analysis could be limited
to scanning for only PHCs, saving time and money. Special adsor-
bents and sampling conditions can be used for specific PHCs if
desired, while continued multimedia sampling will provide a base
for analysis of additional PHCs that may be identified during the
course of cleanup operations.
- Passive Dosimeters
A less traditional method of sampling is the use of passive dosi-
meters. Th*-f£w passive dosimeters now available are only for
gases and vapors. Passive dosimeters are used primarily to monitor
personal exposure, but they can be used to monitor areas. Passive
monitors are divided into two groups:
— Diffusion samplers, in which molecules move across a concentra-
tion gradient, usually achieved within a stagnant layer of air,
between the contaminated atmosphere and the indicator material.
8-6
-------
Permeation devices, which rely on the natural permeation of a
contaminant through a membrane. A suUaole membrane is select-
ed that is easily permeated by the contaminant of interest and
impermeable to all others. Permeation dosimeters are therefore
useful in picking out a single contaminant from a mixture of
possible interfering contaminants.
Some passive dosimeters may be read directly, as are DRIs and
colorimetric length-of-stain tubes. Others require laboratory
analysis similiar to that done on solid sorbents.
VIII. PERSONNEL MONITORING
In addition to area atmospheric sampling, personnel monitoring - both
active and passive - can be used to sample for air contaminants. Repre-
sentative workers are equipped with personal samplers to indicate con-
taminants at specific locations or for specific work being done.
Placed on workers, generally within 1 foot of the mouth and nose, the
monitors indicate the potential for the worker to inhale the con-
taminant.
IX. CALIBRATION
As a rule, the total air sampling system should be calibrated rather
than the pump alone. Proper calibration is essential for correct
operation and for accurate interpretation of resultant data. As a
minimum, the system should be calibrated prior to and after use. The
overall frequency of calibration will depend upon the general handling
and use of a given sampling system. Pump mechanisms should be recali-
brated after repair, -when newly purchased, and following suspected
abuse. Calibration methods can be found in the NIOSH Manual of
Analytical Methods (Volumes 1-7).
X. METEOROLGICAL CONSIDERATIONS
Meteorological information is an integral part of an air surveillance
program. Data concerning wind speed and direction, temperature,
barometric pressure, and humidity, singularly or in combination,
a-P€ needed for:
- Selecting air sampling locations.
- Calculating air dispersion.
- Calibrating instruments.
- Determining population at risk or environmental exposure from
airborne contaminants.
8-7
-------
Knowledge of wind speed and direction is necessary to effectively
place air samplers. In source-orient-ed ambient air sampling
particularly, samplers need to be located downwind (at different
distances) of the source and others placed to collect background
samples. Shifts in wind direction must be known and samplers re-
located or corrections made for the shifts. In addition, atmodpheric
simulation models for predicting contaminant dispersion and concen-
tration need windspeed and direction as inputs for predictive calcu-
lations. Information may be needed concerning the frequency and
intensity with which that winds blow from certain directions (wind-
rose data), consequently, the wind direction must be continually
monitored.
Air sampling systems need to be calibrated before use and corrections
in the calibration curves made for temperature and pressure. After
sampling, sampled air volumes are also corrected for temperature and
pressure variations. This requires knowing air temperature and
pressure.
Air sampling is sometimes designed to assess population exposure (and
frequently potential worker exposure). Air samplers are generally
located in population centers irrespective of wind direction. Even
in these instances, however, meteorological data is needed for air
dispersion modeling. Models are then used to predict or verify
population-oriented sampling results.
Proper data is collected by having meteorological stations on site or
obtaining it from one or more of several government or private
organizations which routinely collect such data. The choice of how
information is obtained depends on the availability of reliable data
at the location desired, resources•needed to obtain meteorological
equipment, accuracy of information needed, and use of information.
8-8
-------
ANNEX 5
GUIDE TO ENVIRONMENTAL RESPONSE TEAM'S
AIR SURVEILLANCE PROGRAM
I. APPROACH
A variety of long-term air surveillance programs can be designed to
detect a wide range of airborne compounds. To implement any program
a number of factors must be considered, including type of equipment,
costs, personnel required, accuracy of analysis, time required to
obtain results (turn-around-time), and availability of analytical
laboratories.
One approach to air surveillance, developer! and used by the USEPA
Environmental Response Team (ERT), is described here. This program
achieves a reasonable balance between cost, accuracy, and time in
obtaining data using a combination of direct reading instruments
(DRIs) and air sampling systems to:
- Rapidly survey for airborne organic vapors and gases.
Identify and measure organic vapors and gases.
- Identify and measure particulates and inorganic vapors and gases.
The approach is based on:
- Using flame ionization detectors (FIDs) and/or photoionization
detectors (PIDs) for initial detection of total organic gases and
vapors and for periodic site surveys (for total organics). Equip-
ped with strip chart recorders, the detectors are used as area
monitors to record total organic concentration and changes in
concentration over a period of time. Calibrated to specific
organic contaminants, they are used to detect and measure those
substances.
- Collecting area air samples using personal pumps and organic gas/
vapor collection tubes. Samples are analyzed using the gas chroma-
—tograph (GC) capabilities of field instruments. Selected samples
are also analyzed in laboratories accredited by the American
Industrial Hygiene Association (AIHA).
- Using PIDs and/or FIDs (as a survey instrument or GC) to provide
real-time data and to screen the number of samples needed for
laboratory analysis.
A5-1
-------
Sampling for participates, inorganic acids, aromatic amines, *aio-
genated pesticides, etc., when they are known to be involved or
when there are indications that these substances may be a problem.
II. EQUIPMENT
At present, the following equipment is used for organic gas/vapor
monitoring however, other equivalent equipment can be substituted:
- HNU Systems Photoionizer (PID)
- Foxboro OVA (FID)
- MDA Accuhaler 808 Sampling Pump
- Gillian Model Number HFS-UT113 Sampling Pump
- Tenax adsorption tubes (metal)
- Carbon-packed adsorption tubes (metal)
- Carbon-packed adsorption tubes (glass)
— 150 milligram and 600 milligram sizes
III. PROCEDURE
This procedure is generally applicable to most responses. However,
since each incident is unique, modifications may be needed.
Organic Gases and Vapors. The sequence for monitoring organic gases
and vapors consists of several steps.
- Determine total background concentrations.
- Determine total concentration on-site.
- Collect on-site area samples.
Identify specific contaminants.
Background concentrations. Background readings of total organic gases
and vapors, using DRIs (FID/PID), are made upwind of the site in areas
not expected to contain air contaminants. If industries, highways, or
other potential sources contribute to concentrations on-site, these
contributions should be determined. Depending' on the situation and
the time available, additional monitoring should be done nearby to
determTrre if contaminants are leaving the site.
Concentrations on-site. The on-site area is monitored (using DRIs)
for totalgas/vaporconcentrations, measured at both ground and
breathing zone levels. The initial walk-throughs are to determine
general ambient concentrations and to locate higher-than ambient
concentrations (hot-spots).
A5-2
-------
TABLE 4-1 (Cont'd.)
Monitoring Equipment
Hazard
Ambient Level
Action
Colorimetric tubes
Photoionization
detector (PID)
Organic and
Inorganic
vapors/gases
Organic
vapors/gases
Flame ionization
detector (FID)
Organic
vapors/gases
Depends on
chemical
1) Depends on
species
2) Total
response
mode
1) Depends on
chemical
2) Total
response
mode
Consult standard
reference manual for
air concentrations/
toxicity data.
Consult standard
reference manuals
for air concentrations/
toxicity data.
Consult EPA Standard
Operating Safety Guides,
Consult standard reference
manuals for air concen-
trations/toxicity data.
Consult EPA Standard
Operating Safety Guides.
4-7
-------
PART 5
SITE ENTRY - LEVELS OF PROTECTION
I. INTRODUCTION
Personnel must wear protective equipment when response activities
involve known or suspected atmospheric contamination, when vapors,
gases, or particulates may be generated by site activities, or when
direct contact with skin-affecting substances may occur. Full face-
piece respirators protect lungs, gastrointestinal tract, and eyes
against airborne toxicants. Chemical-resistant clothing protects the
skin from contact with skin-destructive and absorbable chemicals.
Good personal hygiene limits or prevents ingestion of material.
Equipment to protect the body against contact with known or antici-
pated toxic chemicals has been divided into four categories according
to the degree of protection afforded:
- level A: Should be worn when the highest level of respiratory,
skin, and eye protection is needed.
- Level B: Should be worn when the highest level of respiratory
protection is needed, but a lesser level of skin protection.
- Level C: Should be worn when the criteria for using air-purifying
respirators are met.
P' Should be worn only as a work uniform and not on any
site with respiratory or skin hazards. It provides no protection
against chemical hazards.
The Level of Protection selected should be based on:
- Type and measured concentration of the chemical substance
in the ambient atmosphere and its toxicity.
- Potential for exposure to substances in air, splashes of liquids,
or other direct contact with material due to work being done.
In_situations where the type of chemical, concentration, and
possibilities of contact are not known, the appropriate Level of
Protection must be selected based on professional experience and
judgment until the hazards can be better identified.
While personnel protective equipment reduces the potential for contact
with toxic substances, ensuring the health and safety of responders
requires, in addition, safe work practices, decontamination, site
entry protocols, and other safety procedures. Together, these provide
an integrated approach for reducing harm to workers.
5-1
-------
II. LEVELS OF PROTECTION
A. Level A Protection
1. Personnel protective equipment
- Supplied-air respirator approved by the Mine Safety and
Health Administration (MSHA) and National Institute for
Occupational Safety and Health (NIOSH).
Respi rators may be:
-- pressure-demand, self-contained breathing apparatus
(SC8A)
or
-- pressure-demand, airline respirator (with escape bottle
for Immediately Dangerous to Life an
-------
atmospheric vapors, gases, or particulates
or
— site operations and work functions involves hig^
potential for splash, immersion, or exposure to un-
expected vapors, gases, or particulates of materials
highly toxic to the skin.
- Substances with a high degree of hazard to the skin are
known or suspected to be present, and skin contact is
possible.
- Operations must be conducted in confined, poorly venti-
lated areas until the absence of substances requiring
Level A protection is determined.
- Direct readings on field Flame lonizatlon Dectors (FID) or
Photoionization Detectors (PID) and similar instruments
indicate high levels of unidentified vapors and gases in
the air. (See Appendixes I and II.)
3. Guidance on selection
a. Fully encapsulating suits are primarily designed to
provide a gas or vapor tight barrier between the wearer
and atmospheric contaminants. Therefore Leve'i A is gen-
erally worn when high concentrations of airborne sub-
stances are known or thought to be present and these
substances could severely effect the skin. Since Level A
requires the use of a self-contained breathing apparatus,
the eyes and respiratory system are also more protected.
Until air surveillance data are available to assist in the
selection of the appropriate Level of Protection, the use
of Level A may have to be based on indirect evidence of
the potential for atmospheric contamination or other means
of skin contact with severe skin affecting substances.
Conditions that may require Level A protection include:
- Confined spaces: Enclosed, confined, or poorly ventilated
areas are conducive to build up of toxic vapors, gases, or
particulates. (Explosive or oxygen-deficient atmospheres
also are more probable in confined spaces.) Confined space
entry does not automatically warrant wearing Level A pro-
tection, but should serve as a cue to carefully consider
and to justify a lower Level of Protection.
- Suspected/known highly toxic substances: Various sub-
stances that are highly toxic especially through skin
5-3
-------
absorption for example, fuming corrosives, cyanide com-
pounds, concentrated pesticides, Department of Tran-
sportation Poison "A" materials, suspected carcinogens,
and infectious substances may be known or suspected to be
involved. Field instruments may not be available to
detect or quantify air concentrations of these materials.
Until these substances are identified and concentrations
measured, maximum protection may be necessary.
Visible emissions: Visible air emissions from leaking
containers or railroad/vehicular tank cars, as well as
smoke from chemical fires and others, indicate high
potential for concentrations of substances that could be
extreme respiratory or skin hazards.
- Job functio- s: Initial site entries are generally walk-
throughs in which instruments and visual observations
are used to make a preliminary evaluation of the hazards.
In initial site entries, Level A should be worn when:
-- there "'* a probability for exposure to high con-
centrat'--s of vapors, gases, or particulates.
-- substances are known or suspected of being extremely
toxic directly to the skin or by being absorbed.
Subsequent entries are to conduct the many activities needed
to reduce the environmental impact of the incident. Levels
of Protection for later operations are based not only on data
obtained from the initial a.nd subsequent environmental moni-
toring, but also on the probability of contamination and ease
of decontamination.
Examples of situations where Level A has been worn are:
- Excavating of soil to sample buried drums suspected of
containing high concentrations of dioxin.
- Entering a cloud of chlorine to repair a value broken in a
railroad accident.
- Handling and moving drums known to contain oleum.
- Responding to accidents involving cyanide, arsenic, and un-
diluted pesticides.
b. The fully encapsulating suit provides the highest degree of
protection to skin, eyes, and respiratory system if the suit
material resists chemicals during the time the suit is worn.
While Level A provides maximum protection, all suit material
may be rapidly permeated and degraded by certain chemicals
5-4
-------
from extremely high air concentrations, splashes, or immersion
of boots or gloves 1n concentrated liquids or sludges. Tnese
limitations snould be recognized when specifying the type of
fully encapsulating suit, Whenever possible, the suit
material should be matched with the substance 1t 1s used
to protect against.
B. Level 8 Protection
1. Personnel protective equipment
- Suppl1ed-a1r respirator (MSHA/N10SH approved).
Respirators may be:
-- pressure-demand, self-contained breathing apparatus
or
-- pressure-demand, airline respirator (with escape bottle
for IOLH or potential for IDLH atmosphere)
- Chemical-resistant clothing (overalls and long-sleeved
jacket; hooded, one or two-piece chemical-splash suit;
disposable chemical-resistant, one-piece suits)
- Long cotton underwear*
- Coveralls*
- Gloves (outer), chemical-resistant
- Gloves (inner)^ chemical-resistant
- Boots (outer), chemical-resistant, steel toe and shank
- Boot covers (outer), chemical-resistant (disposable)*
- Hard hat (face shield)*
- 2-Way radio communications* (intrinsically safe)
2. Criteria for selection
Meeting any one of these criteria warrants use of Level B
protection:
- The type and atmospheric concentration of toxic substances
has been identified and requires a high level of respira-
tory protection, but less skin protection than Level A.
These would-be atmospheres:
'Optional
5-5
-------
-- with concentrations Immediately Dangerous to Life and
Health, but substance or concentration in the air
does not represent a severe skin hazard
or
-- that do not meet the selection criteria permitting the
use of air-purifying respirators.
- The atmosphere contains less than 19.5% oxygen.
It is highly unlikely that the work being done will generate
high concentrations of vapors, gases or particulates, or
splashes of material that will affect the skin of personnel
wearing Level B protection.
- Atmospheric concentrations of unidentified vapors or gases
are indicated by direct readings on instruments such
as the FID or PID or similar instruments, but vapors and
gases are not suspected of containing high levels of
chemicals toxic to skin. (See Appendixes I and II.)
3. Guidance on selection
a. Level B does not afford the maximum skin (and eye) pro-
tection as does a fully encapsulating suit since the
chemical-resistant clothing is not considered gas, vapor,
or particulate tight. However, a good quality, hooded,
chemical-resistant, one-piece garment, with taped wrist,
ankles, and hood does provides a reasonable degree of
protection against splashes and to lower concentrations in
air. At most abandoned hazardous waste sites, ambient
atmospheric gas or vapor levels have not approached concen-
trations sufficiently high to warrant Level A protection.
In all but a few circumstances (where highly toxic mater-
ials are suspected) Level B should provide the protection
needed for initial entry. Subsequent operations at a site
require a revaluation of Level B protection based on the
probability of being splashed by chemicals, their effect
on the skin, the presence of hard-to-detect air contaim-
inants, or the generation of highly toxic gases, vapors,
or particulates, due to the work being done.
b. The chemical-resistant clothing required in Level B is
available in a wide variety of styles, materials, construc-
tion detail, and permeability. One or two-piece garments
are available with or without hoods. Disposal suits with
a variety of fabrics and design characteristics are also
available. Taping joints between the gloves, boots and
suit, and between hood and respirator reduces the pos-
siblity for splash and vapor or gas penetration. These
5-6
-------
factors and other selection cntenu all affect tne Degree
of protection afforded. Therefore, a specialist snc.^c!
select the most effective chemical-resistant clottiing
based on the known or anticipated hazards and job function.
Level B equipment does provides a high level of protection
to the respiratory tract. Generally, if a self-contained
breathing apparatus is required for respiratory protection,
selecting chemical-resistant clothing (Level B) rather than
a fully encapsulating suit (Level A) is based on needing
less protection against known or anticipated substances
affecting the skin. Level B skin protection is selected
by:
- Comparing the concentrations of known or identified
substances in air with skin toxicity data.
- Determining the presence of substances that are destruc-
tive to or readily absorbed through the skin by liquid
splashes, unexpected high levels of gases, vapor, or
particulates, or other means of direct contact.
- Assessing the effect of the substance (at its measured
air concentrations or potential 'for splashing) on the
small areas left unprotected by chemical-resistant
clothing. A hooded garment taped to the mask, and
boots and gloves taped to the suit further reduces area
of exposure.
c. For initial site entry and reconnaissance at an open site,
approaching whenever possible from upwind, Level B protec-
tion (with good quality, hooded, chemical-resistant cloth-
ing) should protect response personnel, providing the
conditions described in selecting Level A are known or
judged to be absent.
C. Level C Protection
1. Personnel protective equipment
- Air-purifying respirator, full-face, canister-equipped
(MSHA/NIOSH approved)
- Chemical-resistant clothing (coveralls; hooded, one-piece
or two-piece chemical splash suit; chemical-resistant hood
and apron; disposable chemical-resistant coveralls)
- Coveralls*
- Long cotton underwear*
- Gloves (outer), chemical-resistant
5-7
-------
- Gloves (Inner), chemical-resistant*
- Soots (outer), chemical-resistant, steel toe and shank
- Boot covers (outer), chemical-resistant (disposable)*
- Hard hat (face shield*)
- Escape mask*
- 2-Way radio communications* (Inherently safe)
2. Criteria for selection
Meeting all of these criteria permits use of Level C protec-
tion:
- Oxygen concentrations are not less than 19.5% by volume.
- Measured air concentrations of identified substances will
be reduced by the respirator below the substance's thres-
hold limit value (TLV) and the concentration is within
the service limit of the canister.
- Atmospheric contaminant concentrations do not exceed IDLH
levels.
- Atmospheric contaminants, liquid splashes, or other
direct contact will not adversely affect any body area
left unprotected by chemical-resistant clothing.
- Job functions do not require self-contained breathing
apparatus.
- Direct readings are a few ppms above background on in-
struments such as the FID or PID. (See Appendices I and
II.)
3. Guidance on selection
a. Level C protection is distinguished from Level 8 by the
equipment used to protect the respiratory system, assuming
the same type of chemical-resistant clothing is used. The
main selection criterion for Level C is that conditions
permit wearing air-purifying respirators.
The air-purifying device must be a full-face respirator
(MSHA/NIOSH approved) equipped with a canister suspended
from the chin or on a harness. Canisters must be able to
*OptionaT
5-8
-------
'Optional
remove the substances encountered. Quarter-or half-masKS
or cheekcartridge, full-face masks should be used only
with the approval of a qualified individual.
In addition, a full-face, air-purifying mask, can be used
only if:
- Substance has adequate warning properties.
- Individual passes a qualitative fit-test for the mask.
- Appropriate cartridge/canister is used, and its service
limit concentration is not exceeded.
An air surveillance program is part of all response opera-
tions when atmospheric contamination is known or suspected.
It is particularly important that the air be thoroughly
monitored when personnel are wearing air-purifying respira-
tors. Periodic surveillance using direct-reading instru-
ments and air sampling is needed to detect any changes in
air quality necessitating a higher level of respiratory
protection.
Level C protection with a full-face, air-purifying respi-
rator should be worn routinely in an atmosphere only after
the type of air contaminant is identified, concentrations
measured and the criteria for wearing air-purifying respi-
rator met. To permit flexibility in precribing a Level of
Protection at certain environmental incidents, a specialist
could consider .using air-purifying respirators in uniden-
tified vapor/gas concentrations of a few parts per million
above background as indicated by a needle deflection on the
FID or PID. However a needle deflection of a few parts per
million above background should not be the sole criterion
for selecting Level C. Since the individual components may
never be completely identified, a decision on continuous
wearing of Level C must be made after assessing all safety
considerations, including:
- The presence of (or potential for) organic or inorganic
vapors/gases against which a canister is ineffective or
has a short service life.
- The known (or suspected) presence in air of substances
with low TLVs or IDLH levels,
- The presence of particulates in air.
- The errors associated with both the instruments and
monitoring procedures used.
5-9
-------
The presence of (or potential for) substances in air
which do not elicit a response on the instrument
used.
The potential for higher concentrations in the ambient
atmosphere or in the air adjacent to specific site
operations.
d. The continuous use of air-purifying respirators (Level C)
must be based on the identification of the substances
contributing to the total vapor or gas concentration and
the application of published criteria for the routine use
of air-purifying devices. Unidentified ambient concen-
trations of organic vapors or gases in air approaching or
exceeding a few ppm above background require, as a mini-
mum, Level B protection.
D. Level D Protection
1. Personnel protective equipment
- Coveralls
- Gloves*
- Boots/shoes, leather or chemical-resistant, steel toe and
shank
- Safety glasses or chemical splash goggles*
- Hard hat (face shield)*
2. Criteria for selection
Meeting any of these criteria allows use of Level D protection;
- No contaminants are present.
- Work functions preclude splashes, immersion, or potential
for unexpected inhalation of any chemicals.
Level D protection is primarily a work uniform. It can be
_^orn only in areas where there is no possibility of
contact with contamination.
III. PROTECTION IN UNKNOWN ENVIRONMENTS
In all incident response, selecting the appropriate personnel pro-
tection equipment 1s one of the first steps in reducing health
effects from toxic substances. Until the toxics hazards at an
environmental incident can be identified and personnel safety measures
5-10
-------
commensurate with the hazards instituted, preliminary measures wil',
have to be based on experience, judgment, and professional knowledge.
One of the first concerns in evaluating an unknown situation is
atmospheric hazards. Toxic concentrations (or potential concentra-
tions) of vapors, gases, and particulates; low oxygen content explo-
sive potential and, to a lesser degree, the possibility of radiation
exposure all represent immediate atmospheric hazards. In addition to
making air measurements to determine these hazards, visual observa-
tion and review of existing data can help determine the potential
risks from other materials.
Once Immediate hazards, other than toxic substances have been elimi-
nated, the initial on-site survey and reconnaissance, which may
consist of more than one entry, continues. Its purpose is to further
characterize toxic hazards and, based on these findings, refine
preliminary safety requirements. As data are obtained from the
Initial survey, the Level of Protection and other safety procedures
are adjusted. Initial data also provide information on which to base
further monitoring and sampling. No one method can determine a Level
of Protection in all unknown environments. Each situation must be
examined individually.
IV. ADDITIONAL CONSIDERATIONS FOR SELECTING LEVELS OF PROTECTION
Other factors which should be considered in selecting the appro-
priate Level of Protection are:
A. Heat and Physical Stress
The use of protective clothing and respirators increases physical
stress, in particular heat stress, on the wearer. Chemical protec-
tive clothing greatly reduces body ventilation and diminishes its
ability to regulate its temperature. Even in moderate ambient
temperatures the diminished capacity of the body to dissipate
heat can result in one or more heat-related problems.
All chemical protective garments can cause heat stress. Some-
what less stress is associated with Level B or C when the
protective clothing does not require the use of a hood, tightly
fitted against the respirator face piece, and taped glove,
boot, suit Interfaces, since more body ventilation and evapora-
tlon may occur. As more body area is covered, the probability
of heat stress Increases. Whenever any chemical-protective
clothing 1s worn, a heat stress recovery monitoring program
must occur (see Part 3, Section V).
Wearing protective equipment also increases the risk of acci-
dents. It is heavy, cumbersome, decreases dexterity, agility,
Interferes with vision, and 1s fatiguing to wear. These factors
5-11
-------
B. Air Surveillance
A program must be established for routine, periodic air surveil-
lance. Without an air surveillance program, any changes could
go undetected and jeopardize response personnel. Surveillance
can be accomplished with various types of air pumps and fil-
tering devices followed by analysis of the filtering media;
portable real-time monitoring instruments located strategically
on-site; personal dosimeters; and periodic walk-throughs by
personnel carrying direct-reading instruments. (See Part 8)
C. Decision-Logic for Selecting Protective Clothing
No adequate criteria, similar to the respiratory protection
decision-logic, are available for selecting protective clothing.
A concentration of a known substance in the air approaching a TLV
or permissible exposure limit for the skin does not automa-
tically warrant a fully encapsulating suit. A hooded, high
quality, chemical-resistant suit may provide adequate pro-
tection. The selection of Level A over Level B is a judgment
that should be made by a qualified individual considering the
following factors:
- The physical form of the potential contaminant. Airborne
substances are more likely for body contact with personnel
wearing non-encapsulating suits, since they are not consid-
ered to be gas or vapor tight.
- Effect of the material on skin:
-- highly hazardous substances are those that are easily
absorbed through the skin causing systemic effects, or
that cause severe skin destruction. Skin contact with
liquids are generally more hazardous than vapors, gases
and particulates.
-- -fess hazardous substances are those that are not easily
absorbed through the skin causing systemic effects, or
that do not cause severe skin destruction
- Concentration of the material - the higher the concentration,
the higher the risk of harm.
5-12
-------
- The potential for contact with the material due to
function and the probability of direct exposure to the small
area of skin unprotected by Level B or C cnemical-resistant
clothing.
0. Chemicals Toxic to Skin
The chemicals listed 1n Appendix III are Identified 1n the 011
and Hazardous Materials Technical Assistance Data Base System
(OHMTADS) as having adverse skin effects ranging from Irritation
to absorption Into the body. Knowledge concerning the presence
or absence of these materials could be useful 1n selecting the
necessary Level of Protection. Other substances affecting the
skin, but not listed 1n OHMTADS, may be present. Therefore, a
major effort should be made to identify all substances.
E, Atmospheric Conditions
Atmospheric conditions such as stability, temperature, wind
direction, wind velocity, and barometric pressure determine the
behavior of contaminants 1n air or the potential for volatile
material getting Into air. These parameters should be consid-
ered 1n determining the need for and Level of Protection
required.
F. Work in Exclusion Zone
For operations 1n the Exclusion Zone (area of potential con-
tamination), different Levels of Protection may be selected,
and various types of chemical-resistant clothing worn. This
selection would be based not only on measured air concen-
trations, but also on the job function, reason for being in the
area, the potential for skin contact or inhalation of the
materials present, and ability to decontaminate the protective
equipment used. (See Part 6)
G. Escape Masks
The use of escape masks 1s an option in Level C protection. A
specialist should determine their use on a case-by-case basis.
Escape masks could also be strategically located on-s1te 1n areas
that have higher possibilities for harmful exposure.
V. VAPOR OR GAS CONCENTRATIONS AS INDICATED BY DIRECT-READING INSTRUMENTS
Instruments such as the FID and PID can be used to detect the presence
of many organic vapors or gases either as single compounds or mixtures.
Dial readings are frequently referred to, especially with unidentified
substances, as total vapor and gas concentrations (in ppm). More
5-13
-------
correctly they are deflections of the needle on the dial indicating
an instrument response and does not directly relate to total concen-
tration in the air. As a guide to selecting Level of Protections,
based on dial readings response, the following values could be used.
They should not be the sole criteria for selecting Levels of Pro-
tection.
Dial Reading Level of Protection
Background to 5 ppm C
above background
5 ppm above background 8
to 500 ppm above background
500 ppm above background
t.o 1000 onm abnvp harkarounc
ppm aove acgroun
to 1000 ppm above background
A
Vapor or gas concentration, as indicated by the readout on instruments
such as the FIDs or PIDs are a useful adjunct tt> professional judgment
in selecting the Level of Protection to be worn in an unknown envi-
ronment. It should not be the single selection criterion, but should
be considered with all other available information. Total vapor or
gas concentration as selection criteria for Levels of Protection
should only by used by qualified persons thoroughly familiar with the
information contained in Appendices I and II.
5-14
-------
PART 6
SITE CONTROL - WORK ZONES
I. INTRODUCTION
The activities required during responses to incidents involving
hazardous substances may contribute to the unwanted movement of con-
taminants from the site to uncontaminated areas. Response personnel
and equipment may become contaminated and transfer the material into
clean areas. Material may become airborne due to its volatility or
the disturbance of contaminated soil may cause it to become wind-
blown. To minimize the transfer of hazardous substances from the
site, contamination control procedures are needed. Two general
methods are used: establishing site work zones and removing
contaminants from people and equipment,
II. CONTROL AT THE SITE
A site must be controlled to reduce the possibility of: 1) contact
with any contaminants present and 2) removal of contaminants by per-
sonnel or equipment leaving the site. The possibility of exposure or
translocation of substances can be reduced or eliminated in a number
of ways, including:
- Setting up security and physical barriers to exclude unnecessary
personnel from the general area.
- Minimizing the number of personnel and equipment on-site consistent
with effective operations.
*»
- Establishing work zones within the site.
- Establishing control points to regulate access to work zones.
- Conducting operations in a manner to reduce the exposure of person-
nel and equipment and to eliminate the potential for airborne
dispersion.
- Implementing appropriate decontamination procedures.
in. WORK zones
One method of preventing or reducing the migration of contaminants
is to delineate zones on the site in which prescribed operations occur.
Movement of personnel and equipment between zones and onto the site
6-1
-------
W9
I
2
I
f
"3-4.
-------
itself would be limited by access control points. By these means,,
Three contiguous zones (Figure 6-1) are recommended:
Zone 1: Exclusion Zone
lone 2: Contamination Reduction Zone
lone 3: Support Zone
A. Zone 1: Exclusion Zone
The Exclusion Zone, the innermost of three areas, is the zone
where contamination does or could occur. All people entering the
Exclusion Zone must wear prescribed Levels of Protection. An
entry and exit check point must be established at the periphery
of the Exclusion Zone to regu-late the flow of personnel and
equipment into and out of the zone and to verify that the proced-
ures established to enter and exit are followed.
The outer boundary of Zone 1, the Hotline, is initially estab-
lished by visually surveying the immediate environs of the
incident and determining where the hazardous substances involved
are located; where any drainage, leachate, or spilled material
is; and whether any discolorations are visible. Guidance in
determining the boundaries is also provided by data from the
initial site survey indicating the presence of organic or in-
organic vapors/gases or particulates in air, combustible gases,
and radiation, or the results of water and soil sampling.
Additional factors that should be considered include the distances
needed to prevent fire or an explosion from affecting personnel
outside the zone, the physical area necessary to conduct site
operations, and the potential for contaminants to be blown from
the area. Once the Hotline has been determined it should be
physically secured, fenced, or well-defined by landmarks. During
subsequent site operations, the boundary may be modified and
adjusted as more information becomes available.
8. Subareas Within the Exclusion Zone
All personnel within the Exclusion Zone must wear the required
Level of Protection. Personnel protective equipment is designated
— based on site-specific conditions including the type of work to
be done and the hazards that might be encountered. Frequently
within the Exclusion Zone, different Levels of Protection are
justified. Subareas are specified and conspicuously marked as to
whether Level A, B, or C protection is required (Figure 6-2). The
Level of Protection is determined by the measured concentration
of substances in air, potential for contamination, and the known
or suspected presence of highly toxic substances.
6-3
-------
Different Levels of Protection in the Exclusion Zone might also
be designated by job assignment. For example, collecting samples
from open containers might require Level B protection, while for
walk-through ambient air monitoring, Level C protection might be
sufficient. The assignment, when appropriate, of different
Levels of Protection within the Exclusion Zone generally makes
for a more flexible, effective, and less costly operation while
still maintaining a high degree of safety.
C. Zone 3: Support Zone
The Support Zone, the outermost part of the site, 1s considered a
noncontamlnated or clean area. Support equipment (command post,
equipment trailer, etc.) 1s located in the zone; traffic 1s
restricted to authorized response personnel. Since normal work
clothes are appropriate within this zone, potentially contaminated
personnel clothing, equipment, and samples are not permitted, but
are left in the Contamination Reduction Zone until they are
decontaminated.
The location of the command post and other support facilities in
the Support Zone depends on a number of factors, including:
- Accessibility: topography; open space available; locations of
highways, railroad tracks; or other limitations.
• Wind direction: preferably the support facilities should be
located upwind of the Exclusion Zone. However, shifts in
wind direction and other conditions may be such that an ideal
location based on wind direction alone does not exist.
- Resources: adequate roads, power lines, water, and shelter.
D. Zone 2: Contamination Reduction Zone
Between the Exclusion Zone and the Support Zone is the Contamina-
tion Reduction Zone which provides a transition between contam-
inated and clean zones. Zone 2 serves as a buffer to further
reduce the probability of the clean zone becoming contaminated or
being affected by other existing hazards. It provides additional
assurance that the physical transfer of contaminating substances
on people, equipment, or in the air is limited through a combina-
tion of decontamination, distance between Exclusion and Support
Zones, aTr dilution, zone restrictions, and work functions.
Initially, the Contamination Reduction Zone 1s considered to be a
noncontamlnated area. At the boundary between the Exclusion and
Contamination Reduction Zones, Contmination Reduction Corridors
(decontamination stations) are established, one for personnel
and one for heavy equipment. Depending on the size of the opera-
tion, more than two corridors may be necessary. Exit from the
6-4
-------
Exclusion Zone is through a Contamination Reduction Corridor. As
operations proceed, the area around the decontamination station
may become contaminated, but to a much lesser degree than tne
Exclusion Zone. On a relative basis, the amount of contaminants
should decrease from the Hotline to the Support Zone due to the
distance involved and the decontamination procedures used.
The boundary between the Support Zone and the Contamination Reduc-
tion Zone, the Contamination Control Line, separates the possibly
low contamination area from the clean Support lone. Access to
the Contamination Reduction Zone from the Support Zone is through
a control point. Personnel entering there would wear the pre-
scribed personnel protective equipment, 1f required, for working
in the Contamination Reduction Zone. Entering the Support Zone
requires removal of any protective equipment worn in the Contami-
nation Reduction Zone.
IV. OTHER CONSIDERATIONS
A. Modifications
The use of a three-zone system, access control points, and exac-
ting decontamination procedures provides a reasonable assurance
against the translocation of contaminating substances. This site
control system is based on a worst case situation. Less string-
ent site control and decontamination procedures may be utilized
if more definitive information is available on the types of
substances involved and hazards they present. This Information
-can be obtained through air monitoring, instrument survey and
sampling, and technical data concerning the characteristics and
behavior of material present.
B. Area Dimensions
The distance between the Hotline, Contamination Control Line, and
command post and the size and shape of each zone have to be based
on conditions specific to each site (Figures 6-2 and 6-3). Con-
siderable judgment is needed to assure that the distances between
zone boundaries are large enough to allow room for the necessary
operations, provide adequate distances to prevent the spread of
contaminants, and eliminate the possibllty of Injury due to ex-
— plosion or fire. Long-term operations would Involve developing
reasonable methods (for example, air surveillance, swipe testing,
and visible deterioration) to determine if material 1s being
transferred between zones and to assist 1n modifying site bound-
aries.
The following criteria should be considered 1n establishing area
dimensions and boundaries:
6-5
-------
- Physical and topographical features of the site.
- Weather conditions.
- Field/Ta&oratory measurements of air contaminants and environ-
mental samples.
- Air dispersion calculations.
- Potential for explosion and flying debris.
- Physical, chemical, toxicological , and other characteristics of
the substances present.
- Cleanup activities required.
- Potential for fire.
- Area needed to conduct operations.
- Decontamination procedures.
- Potential for exposure.
- Proximity to residential or industrial areas.
C. Monitoring and Sampling
To verify that site control procedures are preventing the spread
of contamination, a monitoring and sampling program should be
established. The Support Zone should be periodically monitored
for air contaminants using direct-reading instruments and col-
lecting air samples for particulate, gas, or vapor analysis.
Analysis of soil samples collected in the most heavily trafficked
area would indicate contaminants being carried from the Exclusion
Zone by personnel, equipment, or wind. Occassional swipe tests
should be taken in trailers and other areas used by personnel.
These same types of samples should be collected and air monitored
in the Contamination Reduction Zone. Increased concentrations in
air or other environmental media may indicate a breakdown in
control over the Contamination Reduction Corridor, ineffective
decontamination procedures, or failure to restrict site access.
6-6
-------
0-,'
-------
I
8
O
5-3
-------
PART 7
SITE CONTROL - DECONTAMINATION
I. INTRODUCTION
Personnel responding to hazardous substance incidents may become
contaminated in a number of ways including:
- Contacting vapors, gases, mists, or particulates in the air.
- Being splashed by materials while sampling or opening containers.
- Walking through puddles of liquids or on contaminated soil.
- Using contaminated instruments or equipment.
Protective clothing and respirators help prevent the wearer from
becoming contaminated or inhaling contaminants; while good work
practices help reduce contamination on protective clothing, instru-
ments, and equipment.
Even with these safeguards, contamination may occur. Harmful mate-
rials can be transferred into clean areas, exposing unprotected
personnel. In removing contaminated clothing, personnel may contact
contaminants on the clothing or inhale them. To prevent such occur-
rences, methods to reduce contamination, and decontamination proced-
ures must be developed and established before anyone enters a site
and must continue (modified when necessary) throughout site opera-
tions.
Decontamination consists of physically removing contaminants or
changing their chemical nature to innocuous substances. How extensive
decontamination must be depends on a number of factors, the most
important being the type of contaminants involved. The more harmful
the contaminant, the more extensive and thorough decontamination must
be. Less harmful contaminants may require less decontamination.
Combining decontamination, the correct method of doffing personnel
protective equpment, and the use of site work zones minimizes cross-
contamination from protective clothing to wearer, equipment to
personnel, and one area to another. Only general guidance can be
given on methods and techniques for decontamination. The exact
procedure to use must be determined after evaluating a number of
factors specific to the incident.
II. PRELIMINARY CONSIDERATIONS
A. Initial Planning
The initial decontamination plan assumes all personnel and equip-
ment leaving the Exclusion Zone (area of potential contamination)
7-1
-------
are grossly contaminated. A system is then set up for personnel
decontamination to wash and rinse, at least once, all the pro-
tective equipment worn. This is done in combination with a
sequential doffing of protective equipment, starting at the first
station with the most heavily contaminated item and progressing
to the last station with the least contaminated article. Each
piece procedure requires a separate station.
The spread of contaminants during the washing/doffing process is
further reduced by separating each decontamination station by a
minimum of 3 feet. Ideally, contamination should decrease as a
person moves from one station to another further along in the
line.
While planning site operations, methods should be developed to
prevent the contamination of people and equipment. For example,
using remote sampling techniques, not opening containers by hand,
bagging monitoring instruments, using drum grapplers, watering
down dusty areas, and not walking through areas of obvious con-
tamination would reduce the probability of becoming contaminated
and require a less elaborate decontamination procedure.
The initial decontamination plan is based on a worst-case situ-
ation or assumes no Information is available about the incident.
Specific conditions at the site are then evaluated, including:
- Type of contaminant.
- The amount of contamination.
- Levels of protection required..
- Type of protective clothing worn.
The initial decontamination plan is modified, eliminating unneces-
sary stations or otherwise adapting it to site conditions. For
instance, the initial plan might require a complete wash and
rinse of chemical protective garments. If disposable garments
are worn, the wash/rinse step could be omitted. Wearing dis-
posable boot covers and gloves could eliminate washing and
rinsing these items and reduce the number of stations neededr.
8. Contamination Reduction Corridor
An area within the Contamination Reduction Zone is designated the
Contamination Reduction Corridor (CRC). The CRC controls access
into and out of the Exclusion Zone and confines decontamination
activities to a limited area. The size of the corridor depends
on the number of stations in the decontamination procedure.
7-2
-------
HEAVY EQUIPMENT
DECONTAMINATION
AREA
EXCLUSION
ZONE
u
EXIT
PATH
CONTAMINATION
REDUCTION
ZONE
IS
III
118
LEGEND
— »—
— o^—
„ HOTLINE
CONTAMINATION
° CONTROL LINE
® ACCESS CONTROL
POINT - EXTRANCE
PCTH ACCESS CONTROL
u=aj POINT - EXIT
SUPPORT
ZONE
; DRESSOUT !
I AREA '
i i
i .
i
i—
ENTRY
PATH
CONTAMINATION REDUCTION ZONE LAYOUT
FIGURE 7-1
-------
overall dimensions of work control zones, and amount of space
available at the site. A corridor of 75 feet by 15 feet should
be adequate for full decontamination. Whenever possible, it
snould be a straight path.
The CRC boundaries should be conspicuously marked, with entry and
exit restricted. The far end is the hotline - the boundary
between the Exclusion Zone and the Contamination Reduction Zone.
Personnel exiting the Exclusion Zone must go through the CRC.
Anyone in the CRC should be wearing the Level of Protection
designated for the decontamination crew. Another corridor may be
required for heavy equipment needing decontamination. Within the
CRC, distinct areas are set aside for decontamination of person-
nel, portable field equipment, removed clothing, etc. These
areas should be marked and personnel restricted to those wearing
the appropriate Level of Protection. All activities within the
corridor are confined to decontamination.
Personnel protective clothing, respirators, monitoring equipment,
and sampling supplies are all maintained outside of the CRC.
Personnel don their protective equipment away from the CRC and
enter the Exclusion Zone through a separate access control point
at the hotline.
III. EXTENT OF DECONTAMINATION REQUIRED
A. Modifications of Initial Plan
The original decontamination plan must be adapted to specific
conditions found at incidents. These conditions may require more
or less personnel decontamination than planned, depending on a
number of factors.
1. Type of Contaminant
The extent of personnel decontamination depends on the effects
the contaminants have on the body. Contaminants do not ex-
hibit the same degree »f toxicity (or other hazard). When-
ever it is known or suspected that personnel can become
contaminated with highly toxic or skin-destructive substances,
a full decontamination procedure should be followed. If less
— hazardous materials are involved, the procedure can be down-
graded.
2. Amount of Contamination
The amount of contamination on protective clothing is usually
determined visually. If it is badly contaminated, a thorough
decontamination is generally required. Gross material remain-
ing on the protective clothing for any extended period of
time may degrade or permeate it. This likelihood increases
7-4
-------
with higher air concentrations and greater amounts of liquid
contamination. Gross contamination also Increases the proba-
bility of personnel contact. Swipe tests may help determine
the type and quantity of surface contaminants.
3. Level of Protection
The Level of Protection and specific pieces of clothing worn
determine on a preliminary basis the layout of the decontamin-
ation line. Each Level of Protection Incorporates different
problems 1n decontamination and doffing of the equipment. For
example: decontamination of the harness straps and backpack
assembly of the self-contained breathing apparatus 1s "dif-
ficult. A butyl rubber apron worn over the harness makes
decontamination easier. Clothing variations and different
Levels of Protection may require adding or deleting stations
in the original decontamination procedure.
4. Work Function
The work each person does determines the potential for contact
with hazardous materials. In turn, this dictates the layout
of the decontamination line. For example, observers, photo-
graphers, operators of air samplers, or others in the Ex-
clusion Zone performing tasks that will not bring them in
contact with contaminants may not need to have their garments
washed and rinsed. Others in the Exclusion Zone with a
potential for direct contact with the hazardous material will
require more thorough decontamination. Different decontamin-
ation lines could be set up for different job functions, or
certain stations 1n a line could be omitted for personnel
performing certain tasks.
5. Location of Contamination
Contamination on the upper areas of protective clothing poses
a greater risk to the worker because volatile compounds may
generate a hazardous breathing concentration both for the
worker and for the decontamination personnel. There is also
an increased probability of contact with skin when doffing
the upper part of clothing.
— 6. Reason for Leaving Site
The reason for leaving the Exclusion Zone also determines the
need and extent of decontamination. A worker leaving the
Exclusion Zone to pick up or drop off tools or Instruments
and Immediately returning may not require decontamination. A
worker leaving to get a new air cylinder or to change a
respirator or canister, however, may require some degree of
decontamination. Individuals departing the CRC for a break,
lunch, or at the end of day, must be thoroughly decontaminated.
7-5
-------
B. Effectiveness of Decontamination
There is no method to immediately determine how effective decon-
tamination is in removing contaminants. Discolorations, stains,
corrosive effects, and substances adhering to objects may in-
dicate contaminants have not been removed. However, observable
effects only indicate surface contamination and not permeation
(absorption) into clothing. Also many contaminants are not
easily observed.
A method for determining effectiveness of surface decontamination
is swipe testing. Cloth or paper patches - swipes - are wiped
over predetermined surfaces of the suspect object and analyzed in
a laboratory. Both the inner and outer surfaces of protective
clothing should be swipe tested. Positive indications of both
sets of swipes would indicate surface contamination has not been
removed and substances have penetrated or permeated through the
garment. Swipe tests can also be done on skin or inside clothing.
Permeation of protective garments requires laboratory analysis of
a piece of the material. Both swipe and permeation testing
provide after-the-fact information. Along with visual obser-
vations, results of these tests can help evaluate the effec-
tiveness of decontamination.
C. Equipment
Decontamination equipment, materials, and supplies are generally
selected based on availability. Other considerations are ease of
equipment decontamination or disposability. Most equipment and
supplies can be easily procured. For example, soft-bristle scrub
brushes or long-handle brushes are used to remove contaminants.
Water in buckets or garden sprayers is used for rinsing. Large
galvanized wash tubs or stock tanks can hold wash and rinse
solutions. Children's wading pools can also be used. Large
plastic garbage cans or other similar containers lined with
plastic bags store contaminated clothing and equipment. Contam-
inated liquids can be stored temporarily in metal or plastic cans
or drums. Other gear includes paper or cloth towels for drying
protective clothing and equipment.
D. Decontamination Solution
Personnel-protective equipment, sampling tools, and other equip-
ment are usually decontaminated by scrubbing with detergent-water
using a soft-bristle brush followed by rinsing with copious
amounts of water. While this process may not be fully effective
in removing some contaminants (or in a few cases, contaminants
may react with water); it is a relatively safe option compared
with using a chemical decontaminating solution. This requires
that the contaminant be identified. A decon chemical is then
needed that will change the contaminant into a less harmful
substance. Especially troublesome are unknown substances or
7-6
-------
mixtures from a variety of known or unknown substances. Tne
appropriate decontamination solution must be selected in cons./-
tation with an experienced chemist.
E. Establishment of Procedures
Once decontamination procedures have been established, all person-
nel requiring decontamination must be given precise instructions
(and practice, if necessary). Compliance must he frequently
checked. The time it takes for decontamination must be ascer-
tained. Personnel wearing SCBA's must leave their work area witn
sufficient air to walk to CRC and go through decontamination.
IV. DECONTAMINATION DURING MEDICAL EMERGENCIES
A. Basic Considerations
Part of overall planning for incident response is managing medical
emergencies. The plan should provide for:
- Response team members fully trained in first aid and CPR.
- Arrangements with the nearest medical facility for transporta-
tion and treatment of injured, and for treatment of personnel
suffering from exposure to chemicals.
- Consultation services with a toxicologist.
- Emergency eye washes, showers, and/or wash stations.
- First aid kits, blankets, stretcher, and resuscitator.
In addition, the plan should establish methods for decontaminating
personnel with medical problems and injuries. There is the
possibility that the decontamination may aggravate or cause more
serious health effects. If prompt life-saving first aid and
medical treatment is required, decontamination procedures should
be omitted. Whenever possible, response personnel should accom-
pany contaminated victims to the medical facility to advise on
matters involving decontamination.
B. Physical Injury
Physical injuries can range from a sprained ankle to a compound
fracture, from a minor cut to massive bleeding. Depending on the
seriousness of the injury, treatment may be given at the site by
trained response personnel. For more serious injuries, additional
assistance may be required at the site or the victim may have to
be treated at a medical facility.
7-7
-------
Life-saving care should be instituted Immediately without consid-
ering decontamination. The outside garments can be removed
(depending on the weather) 1f they do not cause delays, Interfere
with treatment, or aggravate the problem. Respirators and back-
pack assemblies must always be removed. Fully encapsulating
suits or chemical-resistant clothing can be cut away. If the
outer contaminated garments cannot be safely removed, the Individ-
ual should be wrapped 1n plastic, rubber, or blankets to help
prevent contaminating the Inside of ambulances and medical person-
nel. Outside garments are then removed at the medical facility.
No attempt should be made to wash or rinse the victim at the
site. One exception would be 1f 1t is known that the Individual
has been contaminated with an extremely toxic or corrosive
Material which could also cause severe Injury or loss of life.
For minor medical problems or Injuries, the normal decontamination
procedure should be followed.
C. Heat Stress
Heat-related Illnesses range from heat fatigue to heat stroke,
the most serious. Heat stroke requires prompt treatment to
prevent Irreversible damage or death. Protective clothing may
have to be cut off. Less serious forms of heat stress require
prompt attention or they may lead to a' heat stroke. Unless the
victim 1s obviously contaminated, decontamination should be
omitted or minimized and treatment begun Immediately.
D. Chemical Exposure
Exposure to chemicals can be divided Into two categories:
Injuries from direct contact, such as add burns or Inhalation
of toxic chemicals.
- Potential Injury due to gross contamination on clothing or
equipment.
For Inhaled contaminants treatment can only be by qualified
physicians. If the contaminant 1s on the skin or 1n the eyes,
Immediate measures must be taken to counteract the substance's
effect. First aid treatment usually 1s flooding the affected
area with water; however, for a few chemicals, water may cause
more severe problems.
When protective clothing 1s grossly contaminated, contaminants
may be transferred to treatment personnel or the wearer and
cause Injuries. Unless severe medical problems have occurred
simultaneously with splashes, the protective clothing should be
washed off as rapidly as possible and carefully removed.
7-8
-------
V. PROTECTION FOR DECONTAMINATION WORKERS
The Level of Protection worn by decontamination workers Is determined
by:
- Expected or visible contamination on workers.
- Type of contaminant and associated respiratory and skin hazards.
- Total vapor/gas concentrations in the contamination reduction
corridor.
- Participates and specific inorganic or organic vapors in the CRC.
- Results of swipe tests.
A. Level C Use
Level C includes a full-face, canister-type air-purifying
respirator, hard hat with face shield (if splash is a problem),
chemical-resistant boots and gloves, and protective clothing.
The body covering recommended is chemical-resistant overalls with
an apron, or chemical-resistant overalls and jacket.
A face shield is recommended to protect against splashes because
respirators alone may not provide this protection. The respirator
should have a canister approved for filtering any specific known
contaminants such as ammonia, organic vapors, acid gases, and
particulates.
B. Level B Use
In situations where site workers may be contaminated with un-
knowns, highly volatile liquids, or highly toxic materials,
decontamination workers should wear Level 8 protection.
Level B protection includes SCBA, hard hat with face shield,
chemical-resistant gloves, and protective covering. The clothing
suggested is chemical-resistant overalls, jacket, and a rubber
apron. The rubber apron protects the SCBA harness assembly and
regulator from becoming contaminated.
VI. DFCONTAMINATION OF EQUIPMENT
Insofar as possible, measures should be taken to prevent contamination
of sampling and monitoring equipment. Sampling devices become con-
taminated, but monitoring instruments, unless they are splashed,
usually do not. Once contaminated, instruments are difficult to
clean without damaging them. Any delicate instrument which ca.nnot be
easily decontaminated should be protected while it is being used. It
7-9
-------
should be placed in a clear plastic bag, and the bag taped and secured
around the instrument. Openings are made in the bag for sample
intake.
A. Decontamination Procedures
1. Sampling devices
Sampling devices require special cleaning. The EPA Regional
Laboratories can provide information on proper decontamination
methods.
2. Tools
Wooden tools are difficult to decontaminate because they
absorb cnnmicaU. They should be kept on site and handled
only by protected workers. At the end of the response,
wooden tools should be discarded. For decontaminating
other tools, Regional Laboratories should be consulted.
3. Respiratf>rr
Certain parts of contaminated respirators, such as the harness
assembly and leather or cloth components, are difficult to
decontaminate. If grossly contaminated, they may have to be
discarded. Rubber components can be soaked in soap and water
and scrubbed with a brush. Regulators must be maintained
according to manufacturer's recommendations. Persons respon-
sible for decontaminating respirators should be thoroughly
trained in respirator maintenance.
4. Heavy Equipment
Bulldozers, trucks, back-hoes, bulking chambers, and other
heavy equipment are difficult to decontaminate. The method
generally used is to wash them with water under high pressure
and/or to scrub accessible parts with detergent/water solution
under pressure, if possible. In some cases, shovels, scoops,
and lifts have been sand blasted or steam cleaned. Particular
care must be given to those components in direct contact with
contaminants such as tires and scoops. Swipe tests should be
utilized to measure effectiveness.
B. Sanitizing of Personnel Protective Equipment
Respirators, reusable protective clothing, and other personal
articles not -only must.be decontaminated before being reused, but
also sanitized. The inside of masks and clothing becomes soiled
due to exhalation, body oils, and perspiration. The manufac-
turer's instructions should be used to sanitize .the respirator
mask. If practical, protective clothing should be machine washed
after a thorough decontamination; otherwise it must be cleaned by
hand.
7-10
-------
C. Persistent Contamination
In some instances, clothing and equipment will become contamin-
anted with substances that cannot be removed by normal aeconta-Mn-
ation procedures. A solvent may be used to remove such contamin-
ation from equipment if it does not destroy or degrade the pro-
tective material. If persistent contamination is expected,
disposable garments should be used. Testing for persistent
contamination of protective clothing and appropriate decon-
tamination must be done by qualified laboratory personnel.
D. Disposal of Contaminated Materials
All materials and equipment used for decontamination must be
disposed of properly. Clothing, tools, buckets, brushes, and
all other equipment that is contaminated must be secured in drums
or other containers and labeled. Clothing not completely decon-
taminated on-s1te should be secured in plastic bags before being
removed from the site.
Contaminated wash and rinse solutions should be contained by
using step-in-containers (for example, child's wading pool) to
hold spent solutions. Another containment method is to dig a
trench about 4 inches deep and line it with plastic. In both
cases the spent solutions are transferred to drums, which are
labeled and disposed of with other substances on site.
VII. ANNEXES
Annex 1, 2, and 3 describe basic decontamination procedures for a
worker wearing Level A, B, or C protection. The basic decontamination
lines (Situation 1), consisting of approximately 19 stations, are
almost identical except for changes necessitated by different pro-
tective clothing or respirators. For each annex, three specific
situations are described 1n which the basic (or full decontamination)
procedure 1s changed to take Into account differences 1n the extent
of contamination, the accompanying changes 1n equipment worn, and
other factors. The situations illustrate decontamination setups
based on known or assumed conditions at an incident. Many other
variations are possible.
Annex 4 describes a minimum layout for Level A personnel decontamin-
ation. The number of Individual stations have been reduced. Although
the decontamination equipment and amount of space required 1s less
than needed 1n the procedures previously described, there is also a
much higher probability of cross-contamination.
7-11
-------
Transient contributors on-site, for examnle, exhausts from engines,
should be avoided. Concentrations are recorded and plotted on a site
map. Additional DRI monitoring is then done to thoroughly define a"y
hot-spots located during the survey.
Area samples. Sampling stations are located throughout the site. The
number and locations depend on evaluating many factors, including hot-
spots (by DRI), active work areas, potentials for high concentrations,
and wind direction. As a minimum, stations should be located in a
clean off-site area (control or background station), exclusion zone,
and downwind of the site. As data are accumulated, location, number
of stations, and frequency of sampling can be adjusted.
Routinely, two 4-hour samples are collected, in the morning and after-
noon respectively, using personal sampling pumps equipped with Tenax
and/or carbon-packed, metal adsorption tubes. Total gas/vapor concen-
tration (using ORI) should also be determined at the start and finish
of each sampling run. The readings obtained may show an approximate
relationship (depending on organics present) which will be helpful
later in placing samplers.
Samples are desorbed with a thermal desorber and analyzed on the OVA-GC
for total organic concentration and number of peaks. Chromatograms
of samples taken at the same location but at different times or from
different stations can be compared. Differences in heights of "total"
peak, number of independent peaks, and relative peak heights, if
judiciously interpreted, are useful for making preliminary judgments
concerning air contaminant problems. Page A5-6 shows a suggested
format for calculating total gas/vapor concentration.
If relatively high concentrations are detected by the initial DRI
surveys samplers equipped with carbon-packed collection tubes (glass)
are run next to Tenax/carbon-packed, metal equipped samplers. The
latter samples are analyzed in the field. The carbon-packed collec-
tion tubes are analyzed by an AIHA accredited laboratory.
Area surveys using DRI are continued routinely two-four times daily.
These surveys are to monitor for general ambient levels, as well as
levels at sampling stations, hot-spots, and other areas of site activ-
ities. As information is accumulated on airborne organics, the
frequency of surveys can be adjusted.
Specific contaminants. Personal monitoring pumps with carbon-packed
collection tubes (glass) are run on the first afternoon, concurrent
with samplers equipped with Tenax/carbon-packed, metal collection
tubes. Generally, when total gas/vapor readings are low and only a
few peaks seen .(from the field GC analysis of morning samples),
100-150 mg carbon-packed 'tubes (glass) are used and operated at a
flow rate of 100 cubic centimeters/minute until approximately 30
liters of air have been collected. Depending on suspected contam-
inants and their concentrations, higher flow rates and/or volumes may
A5-3
-------
be needed. When total gas/vapor readings are high and there are many
peaks (from the morning samples), then larger glass carbon collection
tubes (600 mg) are operated at a flow rate from 0.5 to 1 liters/minute
to collect 90 to 150 liters of air.
The results from laboratory analysis of glass carbon tubes are used
for a number of different purposes, including:
- To identify and measure organic gases and vapors collected during
the sampling period.
- To compare laboratory chromatograms and field chromatograms. If
only a few peaks (but the same number) are seen on each chromatogram
(and identified on the laboratory chromatogram) from samples
collected at the same location, it may be reasonable to assume,
until standards are run on the field GC, that the two chromatograms
are identifying the same materials.
- To identify major contaminants on laboratory chromatograms and
determine what standards to prepare for the field GC. Field GC's
can then be used to identify and measure air contaminants against
laboratory prepared standards.
- To use the field GC as a screening device for determining when
samples should be collected for laboratory analysis, or when
samples previously collected should be analyzed. Changes in the
number of peaks on the field chromatograms from samples collected
at the same location indicate changes in the air, suggesting the
need for collecting additional samples for laboratory analysis.
If desorption equipment is not available for on-site sample analysis,
glass collection tubes should be .collected daily. Only samples
collected every third to fifth day are sent to AIHA accredited labora-
tories for analysis; the remaining samples are stored in a cool place
(preferably refrigerated). Selected stored samples are analyzed if
third to fifth day samples indicate changes in air contaminant pat-
terns. If daily on-site surveys detect low contaminant(s) levels,
then 100-150 mg glass carbon columns are used. If the survey reveals
relatively high levels of contaminants, then 600 mg glass carbon
tubes are used.
The National Institute for Occupational Safety and Health P&CAM Analy-
tical Method No. 127 (see Annex 6) should be followed as closely as
possible. Flow rates and collection tubes described in this guide
are primarily for organic solvents. If other than organic solvents
are suspected, then the NIOSH Manual of Analytical Methods (Volume
1-7) should be consulted for the appropriate collection media and
flow rates. Table 1 lists the organic solvents identified by the
NIOSH P4CAM No. 127, many of which are found at hazardous waste
sites. These are identified for possible gas chromatography/mass
spectrometry analysis.
A5-4
-------
Particulates and Inorganic Gases and Vapors. Sampling for oa"ticu-
lates is not done routinely. If these types of air contaminants are
Known or suspected to exist, a sampling program is institute:? *:~
them. Incidents where these contaminants might be present are:
fires involving pesticides or chemicals, incidents involving heavy
metals, arsenic, or cyanide compounds, or mitigation operations tnat
create dust (from contaminated soil and excavation of contaminated
soil).
Sampling media and analytical methods for these air contaminants
should follow guidance given in the NIOSH Manual of Analytical
Methods.
A5-5
-------
SAMPLE CALCULATION
1. Volume sampled by MDA Accuhaler 808 Personal Sampling Pump:
Volume sampled (cc) = (final stroke count - initial stroke count)
X (cc's/stroke*) X (multiplier factor for orifice used**)
*Specified on pump itself.
**Specified in pump operations manual and Table 2. (for MDA Accuhaler)
Calculation:
At beginning of sampling period, Accuhaler stroke counter reads
16292.9. At end of sampling period, it reads 16632.9. What is the
volume of air sampled?
Volume sampled (cc) = 16632.9 (final stroke count) - 16292.9 (initial
stroke count) X 5.7 (cc/pump stroke) X 1.1 (multiplier for orifice)
Volume sampled = 2131.8 cc or 2.1 liters.
2. Reporting Format (for OVA GC Thermal Desorber)
a. Total GC Mode: Total concentration determined = 22 ppm as
CH4 (methane)
b. Time weighted = volume desorbed (liters) X concentration (ppm)
average (ppm) volume collected (liters)
= 0.300 (liter) X 22 (ppm) = 3.14 ppm as CH4 (methane)
2.1 (liters)
c. Peaks: GC mode
4 peaks observed
d. Survey Concentration (total organics by DRI)
Start of sampling period ppm, time
End of sampling period ppm, time
ATTACH CHROMATOGRAM
A5-6
-------
TABLE 1
Organic Solvents Identified by P&CAM Analytic Method No. 127
Organic Solvent Molecular Weight
Acetone 58.1
Benzene 78.1
Carbon tetrachloride 154.0
Chloroform 119.0
Dichloromethane 84.9
p-Dioxane 88.1
Ethylene dichloride 99.0
Methyl ethyl ketone 72.1
Styrene 104.0
Tetrachloroethylene 166.0
Toluene 92.1
1,1-,2-Trichloroethane 133.0
1,1,1-Trichloroethane 133.0
(methyl chloroform)
Trichloroethylene 131.0
Xylene 106.0
Reference: Manual of Analytical Methods
U.S. Department of Health Education & Welfare,
Public Health Service, Center for Disease Control
National Institute of Occupational Safety & Health,
OHEW (NIOSH) Publication No. 77-157-A
A5-7
-------
TABLE 2
Multiplier Factor for MDA Accuhaler 808
Personal Sampling Pumps
Calibrat ion
at 20 cc/min
Ori fice Col or
Yellow
Orange
Red
Brown
Purple
Blue
Green
Black
Normal Flow Rate - cc/min
100
50
20
10
5
2
1
0.5
Volume/Stroke
Multiplier"
1.1
1.06
1.00
0.99
0.97
Reference: Instruction Manual, Accuhaler, Personnel Sampling Pump
Models 808 and 818
MDA Scientific, Inc., Elmdale Avenue,
Glenview, IL 60025
A5-8
-------
ANNEX 6
ORGANIC SOLVENTS IN AIR
Physical and Chemical Analysis Branch
Analytical Method
Analyte:
Matrix:
Procedure:
Date Issued:
Date Revised:
Organic Solvents
(See Table 1)
Air
Adsorption on charcoal
desorption with carbon
disulfide, GC
9/15/72
2/15/77
Method No.:
Range:
P&CAM 127
For the specific
compound, refer
to Table 1
Precision: 10.5% RSD
Classification: See Table 1
1. Principle of the Method
1.1 A known volume of air is drawn through a charcoal tube to trap the organic vapors present.
1.2 The charcoal in the tube is transferred to a small, graduated test tube and desorbed with
carbon disulfide.
1.3 An aliquot of the desorbed sample is injected into a gas chromatograph.
1.4 The area of the resulting peak is determined and compared with areas obtained from the
injection of standards.
2. Range and Sensitivity
The lower limit in mg/sample for the specific compound at 16 x 1 attenuation on a gas chromato-
,graph fitted with a 10:1 splitter is shown in Table 1. This value can be lowered by reducing the
attenuation or by eliminating the 10:1 splitter.
3. Interferences
3.1 When the amount of water in the air is so great that condensation actually occurs in the tube,
organic vapors wilt not be trapped. Preliminary experiments indicate that high humidity
severely decreases the breakthrough volume.
3.2 When two or more solvents are known or suspected to be present in the air, such information
(including their suspected identities), should be transmitted with the sample, since with dif-
ferences in polarity, one may displace another from the charcoal.
3.3 It must be emphasized that any compound which has the same retention time as the specific
compound under study at the operating conditions described in this method is an interference.
Hence, retention time data on a single column, or even on a number of columns, cannot be
considered as proof of chemical identity. For this reason it is important that a sample of
the bulk solvent(s) be submitted at the same time so that identity(ies) can be established by
other means.
127-1
A6-1
-------
3.4 If the possibility of interference exists, separation conditions (column packing, temperatures,
etc.) must be changed to circumvent the problem.
4. Precision and Accuracy
4.1 The mean relative standard deviation of the analytical method is 8% (11.4).
4.2 The mean relative standard deviation of the analytical method plus field sampling using an
approved personal sampling pump is 10% (11.4). Pan of the error associated with the
method is related to uncertainties in the sample volume collected. If a more powerful vacuum
pump with associated gas-volume integrating equipment is used, sampling precision can be
improved.
4.3 The accuracy of the overall sampling and analytical method is 10% (NIOSH-unpublished
data) when the personal sampling pump is calibrated with a charcoal tube in the line.
5. Advantages and Disadvantages of the Method
5.1 The sampling device is small, portable, and involves no liquids. Interferences are minimal,
and most of those which do occur can be eliminated by altering chromatographic conditions.
The tubes are analyzed by means of a quick, instrumental method. The method can also be
used for the simultaneous analysis of two or more solvents suspected to be present in the
same sample by simply changing gas chromatographic conditions from isothermal to a tem-
perature-programmed mode of operation.
5.2 One disadvantage of the method is that the amount of sample which can be taken is limited
by the number of milligrams that the tube will hold before overloading. When the sample
value obtained for the backup section of the charcoal tube exceeds 25% of that found on
the front section, the possibility of sample loss exists. During sample storage, the more
volatile compounds will migrate throughout the tube until equilibrium is reached (33% of
the sample on the backup section).
5.3 Furthermore, the precision of the method is limited by the reproducibility of the pressure
drop across the tubes. This drop will affect the flow rate and cause the volume to be im-
precise, because the pump is usually calibrated for one tube only.
6. Apparatus
6.1 An approved and calibrated personal sampling pump for personal samples. For an area
sample, any vacuum pump whose flow can be determined accurately at 1 liter per minute
or less.
6.2 Charcoal tubes: glass tube with both ends flame sealed. 7 cm long with a 6-mra O.O. and a
4-mm I.O., containing 2 sections of 20/40 mesh activated charcoal separated by a 2-mm
portion of urethane foam. The activated charcoal is prepared from coconut shells and is
fired at 600°C prior to packing. The absorbing section contains 100 mg of charcoal, the
backup section 50 mg. A 3-mm portion of urethane foam is placed between the outlet end of
the tube and the backup section. A plug of silylated glass wool is placed in front of the
absorbing section. The pressure drop across the tube must be less than one inch of mercury
at a flow rate of 1 1pm.
6.3 Gas chromatograph equipped with a flame ionization detector.
6.4 Column (20 ft X '/i in) with 10% FFAP stationary phase on 80/100 mesh, acid-washed
DMCS Chromosorb W solid support. Other columns capable of performing the required
separations may be used.
127-2
A6-2
-------
6.5 A mechanical or electronic integrator or a recorder and some method for determining p«ak
area.
6.6 Microcentnluge tubes, 2.5 ml, graduated.
6.7 Hamilton syringes: 10 n\, and convenient sizes for making standards.
$.8 Pipets: 0.5-ml delivery pipets or 1.0-ml type graduated in 0.1-ml increments.
6.9 Volumetric flasks: 10 ml or convenient sizes for making standard solutions.
7. Reagents
7.1 Spectroquality carbon disulfide (Matheson Coleman and Bell).
7.2 Sample of the specific compound under study, preferably chromatoqualhy grade.
7.3 Bureau of Mines Grade A helium.
7.4 Prepurified hydrogen.
7.5 Filtered compressed air.
8. Procedure
8.1 Cleaning of Equipment: All glassware used for the laboratory analysis should be detergent
washed and thoroughly rinsed with tap water and distilled water.
8.2 Calibration of Personal Pumps. Each personal pump must be calibrated with a representa-
tive charcoal tube in the line. This will minimize errors associated with uncertainties in
the sample volume collected.
8.3 Collection and Shipping of Samples
8.3.1 Immediately before sampling, the ends of the tube should be broken to provide an
opening at least one-half the internal diameter of the tube (2 mm).
8.3.2 The small section of charcoal is used as a back-up and should be positioned nearest
the sampling pump.
8.3.3 The charcoal tube should be vertical during sampling to reduce channeling through
the charcoal.
8.3.4 Air being sampled should not be passed through any hose or tubing before entering
the charcoal tube.
8.3.5 The flow, time, and/or volume must be measured as accurately as possible. The sam-
ple should be taken at a flow rate of 1 1pm or less to attain the total sample volume
required. The minimum and maximum sample volumes that should be collected for
each solvent are shown in Table 1. The minimum volume quoted must be collected if
the desired sensitivity is to be achieved.
-JL3.6 The temperature and pressure of the atmosphere being sampled should be measured
and recorded.
8.3.7 The charcoal tubes should be capped with the supplied plastic caps immediately
after sampling. Under no circumstances should rubber caps be used.
8.3.8 One tube should be handled in the same manner as the sample tube (break, seal, and
transport), except lhat.no air is sampled through this tube. This tube should be
labeled as a blank.
8.3.9 Capped tubes should be packed tightly before they are shipped to minimize tube break-
age during shipping.
127-3
A6-3
-------
8.3.10 Samples of the suspected solvent(s) should be submitted to the laboratory for quali-
tative characterization. These liquid bulk samples should not be transported in the
same container as the samples or blank tube. If possible, a bulk air sample (at least
50 I air drawn through tube) should be shipped for qualitative identification purposes
8.4 Analysis of Samples
8.4.1 Preparation of Samples. In preparation for analysis, each charcoal tube is scored
with a file in front of the first section of charcoal and broken open. The glass wool is
removed and discarded. The charcoal in the first (larger) section is transferred to a
small stoppered test tube. The separating section of foam is removed and discarded;
the second section is transferred to another test tube. These two sections are analyzed
separately.
8.4.2 Desorption of Samples. Prior to analysis, one-half ml of carbon disulfidc is pipetted
into each test tube. (All work with carbon disulfide should be performed in a hood
because of its high toxicity.) Tests indicate that desorption is complete in 30 min-
utes if the sample is stirred occasionally during this period.
8.4.3 GC Conditions. The typical operating conditions for the gas chromatograph are:
1. 85 cc/mm. (70 psig) helium carrier gas flow,
2. 65 cc/min. (24 psig) hydrogen gas flow to detector.
3. 500 cc/min. (50 psig) air flow to detector.
4. 200°C injector temperature.
5. 200°C manifold temperature (detector).
6. Isothermal oven or column temperature — refer to Table 1 for specific compounds.
8.4.4 Injection. The first step in the analysis is the injection of the sample into the gas
chromatograph. To eliminate difficulties arising from blowback or distillation within
the syringe needle, one should employ the solvent flush injection technique. The 10
/J syringe is first flushed with solvent several times to wet the barrel and plunger.
Three microlitcrs of solvent are drawn into the syringe to increase the accuracy and
reproducibility of the injected sample volume. The needle is removed from the sol-
vent, and the plunger is pulled back about 0.2 nl to separate the solvent flush from
the sample with a pocket of air to be used as a marker. The needle is then immersed
in the sample, and a 5-/J aliquot is withdrawn, taking into consideration the volume
of the needle, since the sample in the needle will be completely injected. After the
needle is removed from the sample and prior to injection, the plunger is pulled back
a short distance to minimize evaporation of the sample from the tip of the needle.
Duplicate injections of each sample and standard should be made. No more than a
3% difference in area is to be expected.
8.4.5 Measurement of area. The area of the sample peak is measured by an electronic
integrator or some other suitable form of area measurement, and preliminary results
are read from a standard curve prepared as discussed below.
8.5 Determination of Desorption Efficiency .
8.5.1 Importance of determination. The desorption efficiency of a particular compound can
vary from one laboratory to another and also from one batch of charcoal to another.
Thus, it is necessary to determine at least once the percentage of the specific compound
that is removed in the desorption process for a given compound, provided the same
batch of charcoal is used. NIOSH has found lhat the desorption efficiencies for the
compounds in Table I are between 81% and 100% and vary with each batch of
charcoal.
127-4
A6-4
-------
852 Procedure for determining desorption efficiency Activated charcoal equivalent to
the amount in the first section of the sampling tube (1UU mg) is measured into a
5-cm. 4-mm I D glass tube, flame-sealed at one enJ ''similar to commercially a\a;l-
ablc culture tubes). This charcoal must be from the same batch as that used in ob-
taining the samples and can be obtained from unused charcoal tubes. The open end
is capped with Parafilm. A known amount of the compound is injected directly
into the activated charcoal with a microliter syringe, and the tube is capped with more
Parafilm. The amount injected is usually equivalent to that present in a 10-liter sam-
ple at a concentration equal to the federal standard
At feast five tubes arc prepared in this manner and allowed to stand for at least ever-
night to assure complete absorption of the specific compound onto the charcoal. These
five tubes are referred to as the samples. A parallel blank tube should be treated in
the same manner except that no sample is added to it. The sample and blank tubes
are desorbed and analyzed in exactly the same manner as the sampling tube described
in Section 8.4.
Two or three standards are prepared by injecting the same volume of compound into
0.5 m! of CS-j with the same syringe used in the preparation of the sample. These
are analyzed with the samples.
The dcsorption efficiency equals the difference between the average peak area of the
samples and the peak area of the blank divided by the average peak area of the
standards, or
_ . • Area sample — Area blank
dcsorption efficiency = —— —
Area standard
9. Calibration and Standards
It is convenient to express concentration of standards in terms of mg '0.5 ml CS_- because samples
are desorbed in this amount of CS«. To minimize error due to the volatility of carbon disuifide.
one can inject 20 times the weight into 10 ml of CS;. For example, to prepare a 0.3 mg 0.5 ml
standard, one would inject 6.0 mg into exactly 10 ml of CS: in a glass-stoppered flask. The
density of the specific compound is used to convert 6.0 mg inlo microliters for easy measurement
with a microliter syringe. A series of standards, varying in concentration over the range of
"interest, is prepared and analyzed under the same GC conditions and during the same time period
as the unknown samples. Curves are established by plotting concentration in mg 0.5 ml versus
peak area.
NOTE: Since no internal standard is used in the method, standard solutions must be analyzed
at the same time that the sample analysis is done. This will minimize the effect of known day-
to-day variations and variations during the same day of the FID response.
10. Calculations
10.1 The weight, in mg, corresponding to each peak area is read from the standard curve for the
particular compound. No volume corrections arc needed, because the standard curve is
based on mg''0.5 ml CS- and the volume of sample micctcd is identical to the volume of the
standards injected.
10.2 Corrections for the blank must be made for each sample
Correct mg — mg. — mg,.
127-5
A6-5
-------
where:
mg. = mg found in front section of sample tube
mgt, = mg found in front section of blank tube
A similar procedure is followed for the backup sections.
10.3 The'corrected amounts present in the front and backup sections of the same sample tube
are added to determine the total measured amount in the sample.
10.4 This total weight is divided by the determined desorption efficiency to obtain the corrected
mg per sample.
10.5 The concentration of the analyte in the air sampled can be expressed in mg per m3.
. , _ Corrected mg (Section 10.4) x lOOOQiters/m3)
Air volume sampled (liters)
10.6 Another method of expressing concentration is ppm (corrected to standard conditions of 25 °C
and 760 mm Hg).
ppm .
where:
P = pressure (mm Hg) of air sampled
T = temperature (°C) of air sampled
24.45 = molar volume (liter/mole) at 25 'C and 760 mm Hg
MW = molecular weight
760 = standard pressure (mm Hg)
298 = standard temperature (°K)
11. References
11.1 White, L. D., D. G. Taylor, P. A. Mauer. and R. E. Kupelt "A Convenient Optimized Method
for the Analysis of Selected Solvent Vapors in the Industrial Atmosphere", Am Ind Hyg
Assoc J 31:225, 1970.
11.2 Young. D. M. and A. D. Crowell, Physical Adsorption of Cases, pp. 137-146, Butterworths.
London, 1962.
11.3 Federal Register, 37:202:22139-22142, October 18, 1972.
11.4 NIOSH Contract HSM-99-72-98, Scott Research Laboratories, Inc., "Collaborative Testing
of Activated Charcoal Sampling Tubes for Seven Organic, Solvents", pp. 4-22, 4-27, 1973.
127-6
A6-6
-------
TABLE 1
P«r«m«ter5 Associated With P&CAB Anahtical Method No. 127
Method
Organic Solvent Classification
Acetone
Benzene
Carbon tetrachloride
Chloroform
Dichloromethane
p-Dioxane
Ethylene dichloride
Methyl ethyl ketonc
Styrenc
Tetrachloroethylene
1 , 1 ,2-trichloroethane
1,1,1-trichloroethane
(methyl chloroform)
Trichloroethylene
Toluene
Xylene
D
A
A
A
D
A
D
B
D
B
B
B
A
B
A
Detection limit
(mg/s«mpl«)
—
0.01
0.20
0.10
0.05
0.05
0.05
0.01
0.10
0.06
0.05
0.05
0.05
0.01
0.02
Simple Volume (liters)
Minimum(«) Maiimumf1)
0.5
0.5
10
0.5
0.5
1
1
0.5
1.5
1
10
0.5
1
0.5
0.5
7.7
55
60
13
3.8
18
12
13
34
25
97
13
17
22
31
CC CoUrma
Temp.CC)
60
90
60
80
85
100
90
80
150
130
150
150
90
120
100
Mofecntar
Weigt*
58.1
78.1
154.0
119
84.9
88.1
99.0
72.1
104
166
133
133
131
92.1
106
(a) Minimum volume, in liters, required to measure 0.1 times the OSHA standard
(b) These are breakthrough volumes calculated with data derived from a potential plot (11 2) for activated coconut
charcoal. Concentrations of vapor in air at 5 times the OSHA standard (11.3) or 500 ppm, whichever is lower,
25*C. and 760 torr were assumed These values wiU be as much as 50% lower for atmospheres of high humidity.
The effects of multiple contaminants have not been investigated, but it is suspected that less volatile compounds
may displace more volatile compounds (See 3.1 and 3.2)
127-7
A6-7
-------
PART 9
SITE SAFETY PLAN
I. INTRODUCTION
The purpose of the site safety plan is to establish requirements for
protecting the health and safety of responders during all activities
conducted at an incident. It contains safety information, instruc-
tions, and procedures.
A site safety plan must be prepared and reviewed by qualified personnel
for each hazardous substance response. Before operations at an
incident commence, safety requirements must be written, conspicuously
posted or distributed to all response personnel, and discussed with
them. The safety plan must be periodically reviewed to keep it
current and technically correct.
In non-emergency situations, for example, long-term remedial action
at abandoned hazardous waste sites, safety plans are developed
simultaneously with the general work plan. Workers can become
familiar with the plan before site activities begin. Emergency
response generally requires verbal safety instructions and reliance
on existing standard operating procedures until, when time permits, a
plan can be written.
The plan must contain safety requirements for routine (but hazardous)
response activities and also for unexpected site emergencies. The
major distinction'between routine and emergency site safety planning
is the ability to predict, monitor, and evaluate routine activities.
A site emergency is unpredictable and may occur anytime.
II. GENERAL REQUIREMENTS
The site safety plan must:
- Describe the known hazards and evaluate the risks associated with
the incident and with each activity conducted.
-—tist key personnel and alternates responsible for site safety,
response operations, and for protection of public.
- Describe Levels of Protection to be worn by personnel.
- Delineate work areas.
- Establish procedures to control site access.
- Describe decontamination procedures for personnel and equipment.
- Establish site emergency procedures.
9-1
-------
- Address emergency medical care for injuries and toxicological
problems.
- Describe requirements for an environmental surveillance program.
- Specify any routine and special training required for responders.
- Establish procedures for protecting workers from weather-related
problems.
III. SITE SAFETY PLAN SCOPE AND DETAIL
The plan's scope, detail, and length is based on:
- Information available about the incident.
- Time available to prepare a site-specific plan.
- Reason for responding.
Three general categories of response exist - emergencies, character-
izations and remedial actions. Although considerations for personnel
safety are generic and independent of the response category, in
scope, detail, and length safety requirements and plans vary consid-
erably. These variations are generally due to the reason for
responding (or category of response) , information available, and the
severity of the incident with its concomitant dangers to the respon-
der.
A. Emergencies
1. Situation:
Emergencies generally require prompt action to prevent or
reduce undesirable affects. Immediate hazards of fire,
explosion, and release of toxic vapors or gases are of prime
concern. Emergencies vary greatly in respect to types and
quantities of material, numbers of responders, type of work
required, population affected, and other factors. Emergencies
last from a few hours to a few days.
- Information available: Varies from none to much. Usually
information about the chemicals involved and their associ-
ated hazards is quickly obtained in transportation-related
incidents, or incidents involving fixed facilities.
Determining the substances involved in some incidents,
such as mysterious spills, requires considerable time and
effort.
- Time available: Little time, generally requires prompt
action to bring the inci'dent under control.
- Reason for response: To implement prompt and immediate
9-2
-------
actions to control dangerous or potentially dangerous
situations.
2. Effects on Plan
In emergencies, time is not available to write lengthy and
detailed safety plans. Decisions for responder safety are
based on a continual evaluation of changing conditions.
Responding organizations must rely on their existing written
standard operating safety procedures or a generic plan, and
verbal safety instructions adapted to meet site-specific
conditions. Since heavy reliance is placed on verbal safety
instructions an effective system to keep all responders
informed must be established. Whenever possible, these
incident-specific instructions should be written.
B. Incident Characterization
1. Situation:
In non-emergency responses,for example, preliminary inspec-
tions at abandoned wastes sites or more comprehensive waste
site investigations the objective is to determine and charac-
terize the chemicals and hazards involved, the extent of
contamination, and risks to people and the environment. In
general, initial inspections, detailed investigations, and
extent of contamination surveys are limited in the activities
that are required and number of people involved. Initial or
preliminary inspections generally require 1-2 days. Complete
investigations may last over a longer time period.
- Information available: Much background information.
Generally limited on-site data for initial inspection.
On-site information more fully developed through additional
site visits and investigations.
- Time available: In most cases adequate time is available
to develop written site-specific safety plan,
- Reason for response: To gather data to verify or refute
existing information, to gather information to determine
scope of subsequent investigations, or to collect data for
planning remedial action.
2. Effects on Plan:
Sufficient time is available to write safety plans. In scope
and detail, plans tend to be brief containing safety require-
ments for specific on-site work relevant to collecting data.
As information is developed through additional investigations,
the safety plan is modified and, if necessary, more detailed
and specific requirements added.
9-3
-------
C. Remedial Actions
1. Situation:
Remedial actions are cleanups which last over a long period
of time. They commence after more immediate problems at an
emergency have been controlled, or they involve the mitigation
of hazards and restoration of abandoned hazardous waste
sites. Numerous activities are required involving many
people, a logistics and support base, extensive equipment,
and more involved work activities. Remedial actions may
require months to years to completely accomplish.
- Information available: Much known about on-site hazards.
- Time available: Ample time for work planning.
- Reason for response: Systematic and complete control,
cleanup, and restoration.
2. Effects on Plan:
Since ample time is available before work commences, site
safety plan tends to be comprehensive and detailed. From
prior investigations much detail may be known about the
materials or hazards at the site and extent of contamination.
IV. SITE SAFETY PLAN DEVELOPMENT
To develop the plan as much background information as possible should
be obtained, time permitting, about the incident. This would include,
but not be limited to:
Incident location and name.
- Site description.
- Chemicals and quantities involved.
- Hazards associated with each chemical.
- BehaTTor and dispersion of material involved.
- Types of containers, storage, or transportation methods.
- Physical hazards.
- Prevailing weather condition and forecast.
- Surrounding populations and land use.
- Ecologically sensitive areas.
9-4
-------
Faci1ity records.
- Preliminary assessment reports.
Off-site surveys.
Topographic and hydrologic information.
The information initially available or obtained through subsequent
characterization provides a basis for developing a site-specific safety
plan. Information is needed about the chemicals and hazards involved,
movement of material on and off the site, and potential contact with
responders or the public. This type of information is then used along
with the reason for responding (and work plan) to develop the safety
plan. The plan is tailored to the conditions imposed by the incident
and to its environmental setting. As additional information becomes
available the safety plan is modified to protect against the hazards
discerned and to provide for site emergencies that may occur.
V. ROUTINE OPERATIONS
Routine operations are those activities required in responding to an
emergency or a remedial action at a hazardous waste site. These
activities may involve a high degree of risk, but are standard opera-
tions that all incident responses may require.
Safety practices for routine operations closely parallel accepted
industrial hygiene and industrial safety procedures. Whenever a
hazardous incident progresses to the point where operations become
more routine, the associated site safety plan becomes a more refined
document. As a minimum, the following must be included as part of the
site safety plan for routine operations.
- Describe the Known Hazards and Risks
This must include all known or suspected physical, biological,
radiological, or chemical hazards. It is important that all health
related data be kept up-to-date. As air, water, soil, or hazardous
substance monitoring and sampling data becomes available, it must
be evaluated, significant risk or exposure to workers noted, poten-
-Mal impact on public assessed, and changes made in the plan.
These evaluations need to be repeated frequently since much of the
plan is based on this information.
- List Key Personnel and Alternates
The plan must identify key personnel (and alternates) responsible
for site safety. It should also identify key personnel assigned
to various site operations. Telephone numbers, addresses, and
organizations of these people must be listed in the plan and
posted in a conspicuous place.
9-5
-------
- Designate Levels of Protection to be Worn
The Levels of Protection to be worn at locations on-s1te or by
work functions must be designated. This includes the specific
types of respirators and clothing to be worn for each level.
No one shall be permitted in areas requiring personnel protective
equipment unless they have been trained in its use and are wearing
it.
- Delineate Work Areas
Work areas (exclusion zone, contamination reduction zone, and
support zone) need to be designated on the site map and the map
posted. The size of zones, zone boundaries, and access control
points into each zone must be marked and made known to all site
workers.
- List Control Procedures
Control procedures must be implemented to prevent unauthorized
access. Site security procedures - fences, signs, security
patrols, and check-in procedures - must be established. Procedures
must also be established to control authorized personnel into work
zones where personnel protection 1s required.
- Establish Decontamination Procedures
Decontamination procedures for personnel and equipment must be
established. Arrangements must also be made for the proper
disposal of contaminated material, solutions, and equipment.
- Address Requirements for an Environmental Surveillance Program
• A program to monitor site hazards must be implemented. This would
include air monitoring and sampling, and other kinds of media
sampling at or around the site that would indicate chemicals
present, their hazards, possible migration, and associated safety
requirements.
- Specify Any Routine and Special Training Required
Personnel must be trained not only in genera! safety procedures and
use of safety equipment, but 1n any^ specialized work they may be
expected to do.
- Establish Procedures for Weather-Related Problems
Weather conditions can affect site work. Temperature extremes,
high winds, storms, etc. impact on personnel safety. Work
practices must be established to protect workers from the effects
of weather and shelters provided, when necessary. Temperature
extremes, especially heat and its effect on people wearing protec-
tive clothing, must be considered and procedures established to
monitor for and minimize he-it stress.
9-6
-------
VI. ON-S1TE EMERGENCIES
The plan must address site emergencies - occurrences that require
immediate actions to prevent additional problems or harm to respon-
ders, the public, ^roperty, or the environment. In general, an
responses present a degree of risk to the workers. During routine
operations risk is minimized by establishing good work practices and
using personnel protective equipment. Unpredictable events such as
fire, chemical exposure, or physical injury may occur and must be
anticipated. The plan must contain contingencies for managing them.
- Establish Site Emergency Procedures
— List the names and emergency function of on-site personnel
responsible for emergency actions along with the special
training they have.
— Post the location of nearest telephone (if none at site).
— Provide alternative means for emergency communications.
— Provide a list of emergency services organizations that may be
needed. Names, telephone numbers, and locations must be
posted. Arrangements for using emergency organizations should
be made beforehand. Organizations that might be needed are:
- Fire
- Police
- He-alth
^
Explosive experts
- Local hazardous material response units
- Civil defense
- Rescue
— Address and define procedures for the rapid evacuation of
workers. Clear, audible warnings signals should be estab-
lished, well-marked emergency exits located throughout the
site, and internal and external communications plans devel-
oped. An example of codes that could be used for emergency
operations based on direct-reading instruments is contained in
Annex 7.
-- A complete list of emergency equipment should be attached to
the safety plan. This list should include emergency equipment
available on-site, as well as all available medical, rescue,
transport, fire-fighting, and mitigative equipment.
9-7
-------
Address emergency medical care.
-- Determine location of nearest medical or emergency care
facility. Determine their capability to handle chemical
exposure cases.
-- Arrange for treating, admitting, and transporting of injured
or exposed workers.
-- Post the medical or emergency care facilities location, travel
time, directions, and telephone number.
-- Determine local physician's office location, travel directions,
availability, and post telephone number if other medical care
is not available.
— Determir.- nearest ambulance service and post telephone number.
— List responding organization's physicians, safety officers, or
toxicologists name and telephone number. Also include nearest
poison '^rtrol center, if applicable.
— Maintain accurate records on any exposure or potential exposure
of site workers during an emergency (or routine operations).
The minimum amount of information needed (along with any
medical test results) for personnel exposure records is
contained in Annex 8.
- Advise workers of their duties during an emergency. In particular,
it is imperative that the site safety officers, standby rescue
personnel, decontamination workers-, and emergency medical techni-
cians practice emergency procedures.
- Incorporate into the plan, procedures for the decontamination of
injured workers and for their transport to medical care facilities.
Contamination of transport vehicles, medical care facilities, or
of medical personnel may occur and should be addressed in the
plan. Whenever feasible these procedures should be discussed with
appropriate medical personnel in advance of operations.
- Establish procedures in cooperation with local and state officials
for evacuating residents who live near the site.
VII. IMPLEMENTATION OF THE SITE SAFETY PLAN
The site safety plan, (standard operating safety procedure or a
generic safety plan for emergency response) must be written to avoid
misinterpretation, ambiguity, and mistakes that verbal orders cause.
The plan must be reviewed and approved by qualified personnel. Once
the safety plan is implemented, its needs to be periodically examined
and modified, if necessary, to reflect any changes in s.ite work and
conditions.
9-8
-------
All agencies and organizations which have an active role at the incid-
ent must be familiar with the plan. If possible the plan should
be written in coordination with the organizations involved. Lead
personnel from these organizations should sign the plan to signify
they agree with it and will follow its provisions.
All personnel involved at the site must be familiar with ttve safety
plan, or the parts that pertain to their specific activities.
Frequent safety meeting should be held to keep all informed about
site hazards, changes in operating plans, modifications of safety
requirements, and for exchanges of information. It is the responsi-
bility of personnel Involved at the site as workers or visitors to
comply with the requirements in the plan.
Frequent audits by the incident manager or the safety designee should
be made to determine compliance with the plan's requirements. Any
deviations should be brought to the attention of the incident manager.
Modifications in the plan should be reviewed and approved by appropri-
ate personnel.
VIII. SAMPLE SAFETY PLANS
Annex 9 and 10 are two exaaples of Site Safety Plans. Since no one
sample plan or plan format can adequately address all safety require-
ments for the variety of incidents that occur, they should be used
as a guide to help develop an incident-specific plan. They can also
be used, with necessary adaptation, as generic plans for emergency
response.
In some incidents, the sample plans contained in Annex 9 and 10 might
be satisfactory to use by themself. Filling in the blanks provides an
effective safety plan. In many incidents they should only be consid-
ered as a check list. Since they do not exhaustively cover every
condition which may need addressed, users of these sample plans and
any other type examples must realize their application to any one
incident may not be acceptable. Therefore they must be used with
discretion and tempered by professional judgement and experience.
They are not meant to be all inclusive but examples of considera-
tions, requirements, and format which should be adapted for
incident-specific conditions.
9-9
-------
ANNEX 7
Emergency Operation Codes
Real-Time Monitor
(suggested minimum action plan)
(Site Name)
CODE DESIGNATIONS
1. Green
A. Normal operations
2. YELLOW A
A, Cessation of specific work activity on-site because of:
(1) Continuous organic readings on direct-reading instrument of
* ppm above background (measured 20-30 ft. from point of
suspected release), and
(2) Current or projected meteorological conditions indicate
a probable impact on work activity.
B. If background readings above * ppm are obtained during
cesssation of activity, redesign activity to lower releases
and/or delay that on-site activity until off-site air monitoring
indicates accepted off-site concentration.
C. Site personnel will immediately notify EPA/State of site condi-
tion.
3. Yellow B
A. Termination of all work on-site because of:
(1) Continuous organic readings on direct-reading instrument
* ppm above background (measured approximately 1,000 ft,
from work area or site property limits), and
(2) Current or projected meteorologic conditions indicate a
potential impact on inhabited areas.
B. Site personnel will immediately notify EPA/State of site
conditions.
C. EPA/State will modify off-site air monitoring to meet the
needs of contingency plan.
A7-1
-------
4. RED
A. Termination of all work on-site because of:
(1) Continuous organic readings on direct-reading instruments
* ppm above background (measured downwind at the nearest
occupied area off-site, and
(2) Current or projected meteorologic conditions indicate a po-
tential impact on inhabited areas.
B. Site personnel will Immediatley notify EPA/State of site condi-
tions.
C. Local officials making evacuation/public health decisions will be
advised by EPA/State to:
(7) Release a public health advisory to potentially affected
areas since on-site control methods will not reduce the
source of contamination; and/or
(2) Implement a temporary relocation plan because on-site activi-
ties indicate a potential for continuous above background/
acceptable readings at the nearest inhabited area(s).
Concentration should be determined by appropriate
response personnel.
A7-2
-------
ANNEX 8
RESPONSE SAFETY CHECK-OFF SHEET
(minimum required data)
BEFORE RESPONSE
1.
2.
3.
4.
5.
Incident: Site
a. Response Dates
Type of Response:
Incident Safety PI
Suspected chemical
(c)
Protective Level (s
(a) If Level C - 1
2
Spill
an: Region
(s) involved
) involved:
Identify
. Describe
City
Fire Site
ERT
: (a)
(d)
A B
Canister
air monitoring source
Employee
State
Train Other
Not Developed
(b)
C D
(S)
(b) If Level D JUSTIFY (in comments section at bottom of page).
6. SCBA-Identify Buddy: Name/Organization
7. Last Response: (a) Level Used: A B
(b) Medical Attention/Exam Performed: Yes No
II. AFTER RESPONSE
1. Protective Level Used: A B C D
a. Level C - identify cannister: b. Level D (comment below)
c. Level B or C skin protection: Tyvek/Saran Acid/Rain Other
2. List possible chemical exposure: Same as above: (a)
3. Equipment Decontamination: (a) clothing (b) respirator (c) monitoring
Disposed:
Cleaned:
No Action:
4. Approximate time in exclusion area: hours per day for day
5. Was medical attention/exam required for this response: Yes No
Part I: DATE PREPARED: Reviewed by Date
Part II: DATE PREPARED: Reviewed by Date
COMMENTS:
-------
ANNEX 9
(Suggested format for minimum site safety plan)
SITE SAFETY PLAN
(Name of Hazardous Waste Site/Spill)
1. General Information
As a minimum, all personnel involved with emergency response, waste
site cleanup, drum handling and opening, sampling, site investigations,
etc., will follow the applicable Federal/State rules and regulations. In
addition, all site personnel will follow, as a minimum, U.S. Environmental
Protection Agency, Office of Emergency and Remedial Response, Hazardous
Response Support Division's, Standard Operating Safety Guides and Chapter
9 Hazardous Substance Response, from the EPA Occupation Health and Safety
Manual.
In the event of conflicting plans/requirements, personnel must imple-
ment those safety practices which afford the highest personnel protection.
If site conditions change and it is necessary to modify Levels of
Protection A, B, or C the safety designee on-site shall notify the On-Scene
Coordinator before making recommendations to site personnel.
II. APPROVALS
(SIGNATURE) (SIGNATURE)
On-Scene-Coordinator (OSC)-DATE Safety Officer DATE
(SIGNATURE) (SIGNATURE)
REVIEW COMMITTEE DATE OTHERS DATE
III. Summary of Minimum Requirements
A. The safety officer/designee shall:
1. Describe chemicals, hazards, and risk Involved
2. List key personnel
a. Response manager (OSC)/alternate
b. Safety off1cer(s)/altern«te
c. Other responsible site personnel/alternate
3. Prescribe Levels of Protection
4. Designate work zones: Support area, contamination reduction
area, exclusion area.
5. Implement procedures to control site access.
-------
6. Define decontamination procedures.
7. Delineate entry and escape routes.
8. Identify/contact medical facility, etc.:
a. Fire
b. Ambulance
c. Police
d. Health
e. Etc.
9. List responsible parties and emergency contacts:
a. Federal Government EPA/USCG/CDC/OSHA
b. State Government Environmental/Health Agency
c. County/City Government
10. Establish personnel air monitoring.
11. Specify routine and special training needed
12. Establish procedures for managing weather-related problems.
B. Levels of Protection
1. Level C protection should be used for those job functions
listed belowwhere there is no potential for personnel
contact with either hazardous materials or gases, vapors, or
particulates exceeding requirements for wearing air-purifying
respirators.
(Identify job functions in this paragraph:
e.g. - monitoring/surveillance, supervisors,
observers, etc.)
(Identify specific type of respirator in this paragraph:
e.g."^"approved respirator and type of canister.)
(Identify skin protection in this paragraph:
e.g. - double boots, double gloves, tyvek/saran hooded,
disposable coveralls, etc.)
A9-2
-------
2. Level B protection should be used for those job functions
1isted below which based either on potential or known
site conditions and/or vapor and gas concentrations,
Level C is unsatisfactory.
Identify job functions in this paragraph:
(e.g. - Heavy equipment operations, samplers, equipment/
drum handlers, etc,)
Identify specific respiratory protection in this paragraph:
(e.g. - self-contained breathing apparatus (SCBA), air-line
respirator)
Identify skin protection in this paragraph:
(e.g. - double boots, double gloves, type of chemical re-
sistant garment, etc)
3. If Level A protection is applicable, write a paragraph in
plan listing where and when it is to be worn.
4. Level D is not adequate protection for any work on-site
where potential for exposure is possible.
5. Levels C and B may be modified based on monitoring and
sampling data collected on-site. Safety designee should
not make any modification to the Level of Protection
without discussing it with the On-Scene-Coordinator.
C. Air monitoring - Refer to, Standard Operating Safety
Guides, Part 8, Air Surveillance.
D. Training -
Personnel will have either formal training or prior on-the-
job-training for those tasks they are assigned to at the
incident. All unfamiliar activities will be rehearsed
beforehand.
E. Respiratory Protection Program
All contractor and government personnel involved in on-site
_ activities shall have a written respiratory protection pro-
gram. All personnel wearing air-purifying respirator on-site
are required to be fit-tested. All personnel wearing respir-
ators must have been properly trained in their use. All
respirators are to be properly decontaminated at the end of
each workday.
Persons having beards or facial hair must not wear a respir-
ator if a proper mask-to-face-seal can not be demonstrated by
a fit test. A log of all individuals wearing personnel
protective equipment shall be maintained including time in
the exclusion zone.
A9-3
-------
F. All contractor and government personnel who are exposed to
hazardous levels of chemicals must be enrolled in a medical
monitoring program.
G. General Safety Rules and Equipment
1. There will be no eating, drinking, or smoking in the ex-
clusion or contamination reduction zone.
2. All personnel must pass through the contamination reduc-
tion zone to enter or exit the exclusion zone.
3. As a minimum, emergency eye washes will be on the hot side
of the contamination reduction zone and/or at the work
station.
4. As a minimum, an emergency deluge shower/spray cans are to
be located on the clean side of the contamination reduc-
tion area.
5. At the end of the work day, all personnel working in the
exclusion area shall take a hygienic shower.
6. All supplied breathing air shall be certified as grade D or
better.
7. Where practical, all tools/equipment will be spark proof,
explosion resistant, and/or bonded and grounded.
8. fire extinguishers will be on-site for use on equipment
or small fires only.
9. Since site evacuation may be necessary if an explosion,
fire, or release occurs, an individual shall be assigned
to sound an alert and notify the responsible public
officals if required. For example, the evacuation signal
may be two long blasts every 30 seconds until all person-
nel are evacuated and accounted for.
. An adequately stocked first-aid kit will be on-scene at
all times during operational hours. It is suggested that
an oxygen inhalator respirator be available and a quali-
fied operator present. The location of these items and
the operator shall be posted.
H. Morning Safety Meeting
A morning safety meeting will be conducted for all site per-
sonnel and they will sign a daily attendance sheet and should
sign a master sheet indicating they have read the site safety
plan and will comply. The safety procedures, and the day's
planned operations should be discussed.
A9-4
10
-------
ANNEX 10
1440 TNI 2
5/15/64
OCCUPATIONAL HEALTH AND SAFETY MANUAL
APPENDIX A - SAMPLE SAFETY PLAN
Assistance in preparing the safety plan can be obtained fronv
the OHS
Designee located in Room of Building
or by telephoning .
REVIEW
Response Safety Committee Chairperson
APPROVALS
OSC/SFC
OHS Designee
OIC
PROJECT LEADER
Branch
Building
Room
Phone
DATE OF PLATT PREPARATION
HAZARDOUS SUBSTANCE RESPONSE
Site Name Site No.
HAZARDOUS/SUBSTANCES (known or suspected, contaminated media
or in storage container, etc.):
AlO-i
-------
1440 TNI 2
5/15/84
OCCUPATIONAL HEALTH AND SAFETY MANUAL
HAZARD ASSESSMENT (toxic effects, reactivity, stability,
f lammabi lity, and operational hazards with
sampling, decontaminating, etc.):
MONITORING PROCEDURES (If required by the Project Leader)
Monitoring the site, for identity and concentration of
contamination in all media:
Medical monitoring procedures for evidence of personnel
exposure:
Personnel monitoring procedures:
Ain-2
-------
1443 TN12
5/15/84
OCCUPATIONAL HEALTH AND SAFETY MANUAL
DECONTAMINATION AND DISPOSAL
Decontamination Procedures (contaminated: personnel
surfaces, materials, instruments
equipment, etc):
Disposal Procedures (contaminated equipment, supplies
disposable, washwater):
EMERGENCY PROCEDURES
In event of overt personnel exposure (skin contact,
inhalation, ingestion)
In event of personnel injury:
A1Q-3
-------
1440 TN12
5/15/84
OCCUPATIONAL HEALTH AND SAFETY MANUAL
In event of potential or actual fire or explosion:
In event of potential or actual ionizing radiation exposure
In event of environmental accident (spread of contamination
outside sites) :
EMERGENCY SERVICES (complete here or have separate list available
on-«ite)
Location Telephone
Emergency Medical Facility
Ambulance Service
A10-4
-------
1440 TNI 2
5/15/84
OCCUPATIONAL HEALTH AND SAFETY MANUAL
Location Telephone
Fire Department
Police Department
Poison Control Center
PERSONNEL POTENTIALLY EXPOSED TO HAZARDOUS SUBSTANCES
Personnel Authorized to Enter sit*
1.
-2.
3.
4.
5.
A10-5
-------
1440 TN12
5/15/84
OCCUPATIONAL HEALTH AND SAFETY MANUAL
Other Personnel Assigned to Handle Hazardous Substances
(decontaminate, analyze samples)
1.
2.
3.
4.
5.
ALTERNATIVE WORK PRACTICES
(Describe alternative work practices not specified in this
Chapter. Indicate work practices specified in the
Chapter for which proposed alternative work practices
will serve as substitute.)
APPROPRIATE LITERATURE CITATIONS
LEVEL OF PTOTECTION
SITE MAP
(Attach a site map in advance of a response, if possible, or
at an early stage of an emergency response. Map should be
properly scaled and keyed to local landmarks.)
AIO-6
-------
APPENDIX I
CHARACTERISTICS OF THE HNU PHQTOIONI2ER
AND
ORGANIC VAPOR ANALYZER
I. INTRODUCTION
The HNU Photoionizer and the Foxboro Organic Vapor Analyzer (OVA)* are
used 1n the field to detect a variety of compounds in air. The two
instruments differ in their modes of operation and in the number and
types of compounds they detect (Table 1-1). Both instruments can be
used to detect leaks of volatile substances from drums and tanks,
determine the presence of volatile compounds in soil and water, make
ambient air surveys, and collect continuous air monitoring data. If
personnel are thoroughly trained to operate the instruments and to
interpret the data, these instruments can be valuable tools for
helping to decide the levels of protection to be worn, assist in
determining other safety procedures, and determine subsequent moni-
toring or sampling locations.
II. OVA
The OVA operates in two different modes. In the survey mode, it can
determine approximate total concentration of all detectable species
in air. With the gas chromatograph (GC) option, individual components
can be detected and measured independently, with some detection
limits as low as a few parts per million (ppm).
In the GC mode, a small sample of ambient air is injected into a
chromatographic column and carried through the column by a stream of
hydrogen gas. Contaminants with different chemical structures are
retained on the column for different lengths of time (known as reten-
tion times) and hence are detected separately by the flame ionization
detector. A strip chart recorder can be used to record the retention
times, which are then compared to the retention times of a standard
with known chemical constituents. The sample can either be injected
inttf the column from the air sampling hose or injected directly with
a gas-tight syringe.
In the survey mode, the OVA is internally calibrated to methane by
the manufacturer. When the instrument is adjusted to manufacturer's
instructions it indicates the true concentration of methane in air.
In response to all other detectable compounds, however, the instrument
reading may be higher or lower than the true concentration. Relative
*The use of any trade names does not imply their endorsement by
the U.S. Environmental Protection Agency.
1-1
-------
TABLE 1-1
COMPARISON OF THE OVA AND HNU
OVA
HNU
Response
Application
Detector
Limitations
Calibration gas
Ease of
operation
Detection limits
Response time
Maintenance
Useful range
Service 1ife
Responds to many organic gases
and vapors.
In survey mode, detects total
concentrations of gases and
vapors. In GC mode, identifies
and measures specific compounds.
Responds to many organic
and some inorganic gases
and vapors.
In survey mode, detects
total concentrations of
gases and vapors. Some
identification of compounds
possible, if more than one
probe is used.
Flame ionization detector (FID) Photoionization detector (PID)
Does not respond to inorganic
gases and vapors. Kit available
for temperature control.
Methane
Requires experience to inter-
pret correctly, especially
in GC mode.
0.1 ppm (methane)
2-3 seconds (survey mode)
for CH4
Periodically clean and inspect
particle filters, valve rings,
and burner chamber. Check
calibration and pumping system
for leaks. Recharge battery
after each use.
0-1000 ppm
8 hours; 3 hours with strip
chart recorder.
Does not respond to methane.
Does not detect a compound if
probe has a lower energy than
compound's ionization potential
Benzene
Fairly easy to use and
interpret.
0.1 ppm (benzene)
3 seconds for 90t of
total concentration of benzene
Clean UV lamp frequently.
Check calibration regularly.
Recharge battery after each
use.
0-2000 ppm
10 hours; 5 hours with
strip chart recorder.
1-2
-------
response ratios for substances other than methane are available. To
correctly interpret the readout, it is necessary to either make
calibration charts relating the instrument readings to the true
concentration or to adjust the instrument so that it reads correctly.
This is done by turning the ten-turn gas-select knob, which adjusts
the response of the instrument. The knob is normally set at 3.00 when
calibrated to methane. Calibration to another gas is done by mea-
suring a known concentration of a gas and adjusting the gas select
knob until the instrument reading equals that concentration.
The OVA has an inherent limitation in that it can detect only organic
molecules. Also, it should not be used at temperatures lower than
about 40 degrees Fahrenheit because gases condense in the pump and
column. It has no column temperature control, (although temperature
control kits are available) and since retention times vary with
ambient temperatures for a given column, determinations of contam-
inants are difficult. Despite these limitations, the GC mode can
often provide tentative information on the identity of contaminants
in air without relying on costly, time-consuming laboratory analysis.
III. HNU
The HNU portable photoionizer detects the concentration of organic
gases as well as a few inorganic gases. The basis for detection is
the ionization of gaseous species. Every molecule has a character-
istic ionization potential (I.P.) which is the energy required to
remove an electron from the molecule, yielding a positively charged
ion and the free electron. The incoming gas molecules are subjected
to ultraviolet (UV) radiation, which is energetic enough to ionize
many gaseous compounds. Each molecule is tranformed into charged ion
pairs, creating a current between two electrodes.
Three probes, each containing a different UV light source, are avail-
able for use with the HNU. Ionizing energies of the probe are 9.5,
10.2, and 11.7 electron volts (eV). All three detect many aromatic
and large molecule hydrocarbons. The 10.2 eV and 11.7 eV probes, in
addition, detect some smaller organic molecules and some halogenated
hydrocarbons. The 10.2 eV probe is the most useful for environmental
response work, as it is more durable than the 11.7 eV probe and
detects more compounds than the 9.5 eV probe.
Th« HNU factory calibration gas is benzene. The span potentiometer
(calibration) knob is turned to 9.8 for benzene calibration. A knob
setting of zero increases the response to benzene approximately
tenfold. As with the OVA, the instrument's response can be adjusted
to give more accurate readings for specific gases and eliminate the
necessity for calibration charts.
1-3
-------
While the primary use of the HNU is as a quantitative instrument, it
can also be used to detect certain contaminants, or at least to
narrow the range of possiblities. Noting instrument response to a
contaminant source with different probes can eliminate some conta-
minants from consideration. For instance, a compound's ionization
potential may be such that the 9.5 eV probe produces no response, but
the 10.2 eV and 11.7 eV probes do elicit a response. The HNU does
not detect methane.
The HNU is easier to use than the OVA. Its lower detection limit
is also in the low ppm range. The response time is rapid; the meter
needle reaches 90% of the indicated concentration in 3 seconds for
benzene. It can be zeroed in a contaminated atomosphere and does
not detect methane.
IV. GENERAL CONSIDERATIONS
Both of these Instruments can monitor only certain vapors and gases
in air. Many nonvolatile liquids, toxic solids, particulates, and
other toxic gases and vapors cannot be detected. Because the types
of compounds that the HNU and OVA can potentially detect are only
a fraction of the chemicals possibly present at an incident, a zero
reading on either instrument does not necessarily signify the absence
of air contaminants.
The instruments are non-specific, and their response to different
compounds is relative to the calibration setting. Instrument readings
may be higher or lower than the true concentration. This can be an
especially serious problem when monitoring for total contaminant
concentrations if several different compounds are being detected at
once. In addition, the response of these instruments is not linear
over the entire detection range. Care must therefore be taken when
interpreting the data. All identifications should be reported as
tentative until they can be confirmed by more precise analysis.
Concentrations should be reported in terms of the calibration gas and
span potentiometer or gas-select-knob setting.
Since the OVA and HNU are small, portable Instruments, they cannot be
expected to yield results as accurate as laboratory instruments.
They were originally designed for specific Industrial applications.
They are relatively easy to use and interpret when detecting total
concentrations of Individually known contaminants in air, but
interpretation becomes extremely difficult when trying to quantify
the components of a mixture. Neither instrument can be used as an
indicator for combustible gases or oxygen deficiency.
The OVA (Model 128) 1s certified by Factory Mutual to be used in
Class I, Division 1, Groups A,B,C, and D environments. The HNU is
certified by Factory Mutual for use in Class I, Division 2, Groups,
A, B, C, and D.
1-4
-------
APPENDIX II
RATIONALE FOR RELATING TOTAL ATMOSPHERIC VAPOR/GAS CONCENTRATIONS
TO THE SELECTION OF THE LEVEL OF PROTECTION
I. INTRODUCTION
The objective of using total* atmospheric vapor/gas concentrations for
determining the appropriate Level of Protection is to provide a
numerical criterion for selecting Level A, B, or C. In situations
where the presence of vapors or gases is not known, or if present,
the individual components are unknown, personnel required to enter
that environment must be protected. Until the constituents and
corresponding atmospheric concentrations of vapor, gas, or particulate
can be determined and respiratory and body protection related to the
toxicological properties of the identified substances chosen, total
vapor/gas concentration, with judicious interpretation, can be used
as a guide for selecting personnel protection equipment.
Although total vapor/gas concentration measurements are useful to a
qualified professional for the selection of protective equipment,
caution should be exercised in interpretation. An instrument does
not respond with the same sensitivity to several vapor/gas contam-
inants as it does to a single contaminant. Also since total vapor/
gas field instruments see all contaminants in relation to a specific
calibration gas, the concentration of unknown gases or vapors may be
over or under-estimated.
Suspected carcinogens, particulates , highly hazardous substances, or
other substances that do not elicit an instrument response may be
known or believed to be present. Therefore, the protection level
should not be based solely on the total vapor/gas criterion. Rather,
the level should be selected case-by-case, with special emphasis on
potential exposure and chemical and toxicological characteristics of
the known or suspected material.
II. FACTORS FOR CONSIDERATION
total atmospheric vapor/gas concentrations as a guide
for selecting a Level of Protection, a number of other factors should
also be considered:
- The uses, limitations, and operating characteristics of the
monitoring instruments must be recognized and understood.
Instruments such as the HNU Photoioni zer , Foxboro Organic Vapor
*See Part VII for explanation of term.
II-l
-------
Analyzer (OVA), MIRAN Infrared Spectrophotometer, and others do
not respond identically to the same concentration of a substance
or respond to all substances. Therefore, experience, knowledge,
and good judgement must be used to complement the data obtained
with instruments.
- Other hazards may exist such as gases not detected by the HNU or
OVA, (i.e. phosgene, cyanides, arsenic, chlorine), explosives,
flammable materials, oxygen deficiency, liquid/solid particles, and
liquid or solid chemicals.
- Vapors/gases with a very low TLV or IDLH could be present. Total
readings on instruments, not calibrated to these substances, may
not indicate unsafe conditions.
- The risk to personnel entering an area must be weighed against
the need for entering. Although this assessment is largely a
value judgment, it requires a conscientious balancing of the
variables involved and the risk to personnel against the need to
enter an unknown environment.
- The knowledge that suspected carcinogens or substances extremely
toxic or destructive to skin are present or suspected to be present
(which may not be reflected in total vapor/gas concentration)
requires an evaluation of factors such as the potential for ex-
posure, chemical characteristics of the material, limitation of
instruments, and other considerations specific to the incident.
- What needs to be done on-site must be evaluated. Based upon total
atmospheric vapor concentrations, Level C protection may be judged
adequate; however, tasks su-ch as moving drums, opening containers,
and bulking of materials, which'increase the probability of liquid
splashes or generation of vapors, gases, or particulates, may
require a higher level of protection.
- Before any respiratory protective apparatus is issued, a respir-
atory protection program must be developed and implemented ac-
cording to recognized standards (ANSI Z88.2-1980).
III. LEVEL A PROTECTION (500 to 1,000 PPM ABOVE BACKGROUND)
Level -Ap-protection provides the highest degree of respiratory tract,
skin, and eye protection if the inherent limitations of the personnel
protective equipment are not exceeded. The range of 500 to 1,000
parts per million (ppm) total vapors/gases concentration in air was
selected based on the followjng criteria:
- Although Level A provides protection against air concentrations
greater than 1,000 ppm for most substances, an operational re-
striction of 1,000 ppm is established as a warning flag to:
11-2
-------
evaluate the need to enter environments with unknown
concentrations greater than 1,000 ppm
— identify the specific constituents contributing to the total
concentration and their associated toxic properties
— determine more precisely concentrations of constituents
— evaluate the calibration and/or sensitivity error associated
with the instrument(s)
— evaluate instrument sensitivity to wind velocity, humidity
temperature, etc.
- A limit of 500 ppm total vapors/gases in air was selected as the
value to consider upgrading from Level B to Level A. This concen-
tration was selected to fully protect the skin until the constit-
uents can be identified and measured and substances affecting the
skin excluded.
- The range of 500 to 1,000 ppm is sufficiently conservative to pro-
vide a safe margin of protection if readings are low due to instru-
ment error, calibration, and sensitivity; if higher than antici-
pated concentrations occur; and if substances highly toxic to the
skin are present.
With properly operating portable field equipment, ambient air
concentrations approaching 500 ppm have not routinely been encoun-
tered on hazardous waste sites. High concentrations have been
encountered only in closed buildings, when containers were being
opened, when personnel were working in the spilled contaminants,
or when organic vapors/gases were released in transportation
accidents. A decision to require Level A protection should also
consider the negative aspects: higher probability of accidents due
to cumbersome equipment, and most importantly, the physical stress
caused by heat buildup in fully encapsulating suits.
IV. LEVEL B PROTECTION (5 to 500 ABOVE BACKGROUND)
Level B protection is the minimum Level of Protection recommended
foc^initially entering an open site where the type, concentration,
and presence of airborne vapors are unknown. This Level of Protection
provides a high degree of respiratory protection. Skin and eyes are
also protected, although a small portion of the body (neck and sides
of head) may be exposed. The use of a separate hood or hooded,
chemical-resistant jacket would further reduce the potential for
exposure to this area of the body. Level B impermeable protective
clothing also increases the probability of heat stress.
11-3
-------
A limit of 500 ppm total atmospheric vapor/gas concentration on
portable field instruments has been selected as the upper restriction
on the use of Level B. Although Level B personnel protection should
be adequate for most commonly encountered substances at air concen-
trations higher than 500 ppm, this limit has been selected as a
decision point for a careful evaluation of the risks associated with
higher concentrations. These factors should be considered:
The necessity for entering unknown concentrations higher than 500
ppm wearing Level B protection.
- The probability that substance(s) present are severe skin hazards.
- The work to be done and the increased probability of exposure.
- The need for qualitative and quantitative identification of the
specific components.
Inherent limitations of the instruments used for air monitoring,,
Instrument sensitivity to winds, humidity, temperature, and other
factors.
V. LEVEL C PROTECTION (BACKGROUND TO 5 PPM ABOVE BACKGROUND)
Level C provides skin protection identical to Level B, assuming the
same type of chemical protective clothing is worn, but lesser pro-
tection against inhalation hazards. A range of background to'5 ppm
above ambient background concentrations of vapors/gases in the atmos-
phere has been established as guidance for selecting Level C pro-
tection. Concentrations in the air of unidentified vapors/gases
approaching or exceeding 5 ppm would warrant upgrading respiratory
protection to a self-contained breathing apparatus.
A full-face, air-purifying mask equipped with an organic vapor can-
ister (or a combined organic vapor/particulate canister) provides
protection against low concentrations of most common organic vapors/
gases. There are some substances against which full-face, canister-
equipped masks do not protect, or substances that have very low
Threshold Limit Values or Immediately Dangerous to Life or Health
concentrations. Many of the latter substances are gases or liquids
in theirTTormal state. Gases would only be found in gas cylinders,
while the liquids would not ordinarily be found in standard con-
tainers or drums. Every effort should be made to identify the in-
dividual constituents (and the presence of particulates) contributing
to the total vapor readings of a few parts per million. Respiratory
protective equipment can then be selected accordingly. It is ex-
ceedingly difficult, however, to provide constant, real-time iden-
tification of all components in a vapor cloud with concentrations of
a few parts per million at a site where ambient concentrations are
constantly changing. If highly toxic substances have been ruled out,
11-4
-------
but ambient levels of a few parts per million persist, it is unreas-
onable to assume only self-contained breathing apparatus should be
worn. The continuous use of air-purifying masks in vapor/gas concen-
trations of a few parts per million gives a reasonable assurance that
the respiratory tract is protected, provided that the absence of
highly toxic substances has been confirmed.
Full-face, air-purifying devices provide respiratory protection
against most vapors at greater than 5 ppm; however, until more
definitive qualitative information is available, concentration(s)
greater than 5 ppm indicates that a higher level of respiratory
protection should be used. Also, unanticipated transient excursions
may Increase the concentrations in the environment above the limits
of air-purifying devices. The increased probability of exposure due
to the work being done may require Level 8 protection, even though
ambient levels are low.
VI. INSTRUMENT SENSITIVITY
Although the measurement of total vapor/gas concentrations can be a
useful adjunct to professional judgment in the selection of an appro-
priate Level of Protection, ca'ution should be used in the inter-
pretation of the measuring instrument's readout. The response of an
instrument to a gas or vapor cloud containing two or more substances
does not provide the same sensitivity as measurements involving the
individual pure constituents. Hence the instrument readout may
overestimate or underestimate the concentration of an unknown com-
posite cloud. This same type of inaccuracy could also occur in
measuring a single unknown substance with the instrument calibrated
to a different substance. The idiosyncrasies of each instrument must
be considered in conjunction with the other parameters in selecting
the protection equipment needed.
Using the total vapor/gas concentration as a criterion used to deter-
mine Levels of Protection should provide protection against concen-
trations greater than the instrument's readout. However, when the
upper limits of Level C and B are approached, serious consideration
should be given to selecting a higher Level of Protection. Cloud
constituent(s) must be identified as rapidly as possible and Levels
of Protection based on the toxic properties of the specific sub-
Slance(s) identified.
VII. EXPLANATION OF PHRASE TOTAL ATMOSPHERIC VAPOR/GAS CONCENTRATION
The phrase total atmospheric vapor/gas concentration 1s commonly
used to describe the readout, in ppm, on PIDs and FIOs. More
correctly it should be called a dial reading or needle deflection.
In atmospheres that contain a single vapor/gas or mixtures of
vapors/gases that have not been identified, the Instruments do not
II-5
-------
read the total vapors/gases present only the instrument's response
This response, as indicated by a deflection of the needle in the
dial, does not indicate the true concentration. Accurate dial
readings can only be obtained by calibrating the instrument to the
substance being measured.
[1-6
-------
APPENDIX III
DERMAL TOXICITY DATA
I. SELECTION OF CHEMICALS
The approximately 350 chemicals listed in Table III-l, at the end of
this appendix, are identified in the Oil and Hazardous Materials
Technical Assistance System (OHMTADS) as being dermally active.
Since OHMTADS contains only about 1200 chemicals, or may not indicate
a listed chemical as a skin hazard, other reference sources should
also be consulted.
The data in Table III-l were compiled by a toxicologist through a
special project with the U.S. Environmental Protection Agency. As
with any source of information, the data should be cross-checked
against other standard references.
II. USE OF TABLES
A. Categories
Table III-l divides chemicals into two categories:
Category 1 (more serious), which includes:
- Gases having a systemic dermal toxicity rating of moderate to
extremely hazardous and a skin penetration ranking of moderate
to high.
- Liquids and solids having a systemic dermal toxicity rating of
extremely hazardous and a skin penetration ranking of moderate
to high.
- Gases having a local dermal toxicity rating of moderate to
extremely hazardous.
- Liquids and solids having a local dermal toxicity rating of
extremely hazardous.
Category 2 (less serious), which includes:
- Gases having a systemic dermal toxicity rating of slightly
hazardous and a skin penetration ranking of slight.
- Liquids and solids having a systemic dermal toxicity rating of
slightly hazardous and a skin penetration ranking of moderate
to slight.
III-l
-------
- Gases having a local dermal toxicity rating of slightly haz-
ardous.
- Liquids and solids having a local dermal toxicity rating of
moderate to slightly hazardous.
B. Physical State
The physical state of the chemicals listed 1s their normal state.
In a fire, some listed as solids or liquids could vaporize and
represent a greater hazard to the skin. The chemicals listed may
also be found mixed with other substances, which could change how
they affect the skin.
C. Skin Penetration
Negligible Penetration (solid - polar)
+ Slight Penetration (solid - nonpolar)
+•+ Moderate Penetration (liquid/solid - nonpolar)
+++ High Penetration (gas/liquid - nonpolar)
D. Potency (Systemic)
+++ Extreme Hazard
++ Moderate Hazard
1 mg/kg-50 mg/kg)
50-500 mg/kg)
* Slight Hazard (LD5n,: 500-15,000 mg/kg)
E. Potency (Local)
Extreme - Tissue destruction/necrosis
Moderate - Irritation/infTarnation of skin
Slight - Reddening of skin
Lethal amount to
a 70-kilogram man
drops to 20 ml
1 ounce - 1 pint
(.1 pound)
1 pint - 1 quart
(2.2 pounds)
III. RELATION OF TABLE III-l AND LEVELS OF PROTECTION
The purpose of Table III-l is to provide data that a qualified person
can use in conjunction with other site-specific knowledge to select
protective clothing. The data relate to skin toxicity only and
should not be used to select respiratory protection equipment.
III-2
-------
The known or suspected presence and/or measured concentration of
Category 1 chemicals at or above the listed concentrations warrants
wearing a fully encapsulating suit (Level A). The known or suspected
presence and/or measured concentration cf Category 2 chemicals at or
above the listed concentrations suggests that a lesser level of skin
protection (Level B or C) is needed.
There is no decision-logic for choosing protective clothing as there
is for choosing respiratory protective equipment. The use of a fully
encapsulating suit over other types of chemical-resistant clothing is
generally a judgment made by a qualified individual based on an
evaluation of all pertinent information available about the specific
incident. Other guidance and criteria for selecting personnel pro-
tection equipment are contained in Part 5, Site Entry - Levels of
Protection and in Appendix II.
IV. OTHER REFERENCES
Table III-l does not include all substances affecting the skin.
Other standard references should be consulted, in particular:
- Threshold Limit Values for Chemical Substances and Physical Agents
in the Workroom Environment With Intended Changes for 1982,
American ConferenceofGovernmentalIndustrialHygienists, 6500
Glenway Ave., Building D-5, Cincinnati, OH 45211 (1982).
- NIOSH/OSHA Pocket Guide to Chemical Hazards, U.S. Government
Printing Office, Washington, DC20402 (August 1981).
- Registry of Toxic Effects of Chemical Substances, U.S. Government
Printing Office, Washington, DC20402 (1980).
Whenever possible, data in one reference should be cross-checked with
other references.
III-3
-------
I <_>
^^ ^1^
CO *K
0 0
H-
0
C «S
tO 4)
c
4)
0.
^
U 4)
•^ ^J
V* *
>n ^j
0.
p.
k)
***
+
•a
«^»
r™
o
T-J
5
^
i
Ln
^
H)
**
+
•o
•^•B
^v
0
^|
a»
e
i
t
us
^r
CM
(M
S
rn**
E
en
o
u »—
VI
>^
VI
•f
•o
^•B
^^
O
VI
b
LU
1—
1
in
^/
CM
(M
S
^^^
**E
1
O
f-4
•f
U r-
£ o
VI
"*
+
•o
^•^
0
2
^
a.
i
in
^
«M
l)
VI
t
•o
3
^W
l_
2
VI
LU
•o
£
a.
i—
i
wo
*r
CM
CM
CO
jwj*1
S
E
O
O i—
vi *""
>^
VI
•f
*ity
•*~
^^
o
jj
15
h-
1
CO
*f
CM
o
»— i
•f
u ^~
go
o
v»
VI
+
•o
^^
o
VI
*,
•a
5
a.
i
<<*•
CM
CM
1
*•
f ^
VI
^
•a
^•B
O
VI
i
O
c
V
_^
Q.
O
u
o
JC,
u
«^B
o
1
«r
CM
00
*•*•»
E
w
0
(J •—
£ o
VI
VI
•f
•a
3
^^
•^
VI
u
VI
LU
,
o
t
5T
CM
1
•+•
U
O
•f-
•f
•o
•*«•
3
cr
^^
a>
,
^
u
^_
K
^
>»
JC
LU
1
CM
1
i
1
]
!
U
0
i
!
t
•a
<^
3
cr
•^
i
**** '
fe
E
f^ *
Jh_L f
QJ 1
f
If, •
f
*>,
^» 0}
4-> C-
4; »-
z: -a
F
«V
in-4
-------
o o
^^ fc^
o
u
o
41
C
4) O
JO 4->
10 U
*/> 4J
— c
E4>
U
4> C
Cw O
^^
u
2
f— 4J
15
4) X
0 0
c
o
c 4)
C
41
Cv
-
U 4)
•^ 4J
V) ^
JE V>
u
4^M
S
^J
^^
(VJ
1
$
.-
U
O
+
•o
*—
W)
"o
^£
4->
0.
3C
1
C*J
csj
i
t +
o^
| J
^
>i^
W1
+
^53
<^»
!•—
VI
^"*
0
e
*"•
3^
^C
1
wn
*
Q.E
O O
f^t t.ft
<\j m
$ -t-
^u
o 5
wt
wt
•f
TJ
«^»
3
cr
•—
ft)
"5,
jgj
^&-
•o
l^
VI
•f
•o
•^
3
cr
•—
ft)
V.
J=
c
<
u
•*•>*
4J
4)
^
*
(VI
CO
o. ^^
CL E
(^5 €3
i^^ CD
I^D ^^
* *»
*M CSJ
t
**5
u
0
•f
^
«^»
3
cr
•—
4)
C
0
4J
4)
(J
<
i— <
JC
00
Q.
0.
O
""
t
u
I
Irt
M%
•*•
^
•r"
3
cr
*-
e
u
^»
o
c
5,
^^
4)
C
O
4)
U
<
CM
1
t
•O
U
e
t
•^*
3
cr
•-"
4)
C
O
41
U
•e
o
4)
w
*
^H
"i
in
«— i
a.
Q.
4fl
5
r
o
•4.
t
C —•
— 3
E cr
3 •*-
4)
^O
•r*
i
u
CO
^-»
9^
^j
4)
<
^^
C
"E
in
»— t
i
a.
in
•*
t
i-
o
o
1
cn-o
c —
•»- 3
5^
4)
•fM
U
0
^J
^J
^_
^t
*J
V
*
CV4
i
•4-
$
r- 4)
O 4->
I/I
C
4)
l/t
•f
^3
^v
r*»
O
0)
c
^3
•^M
«^
^
<
Cvi
00
ecro
C 1*^^
o.
c
4)
"*
+
TJ
•^—
3
cr
•—
c
4)
o
^»
**
^«^
1
i
^»-
CO
e
d
EX
fsl
$ t
u «-
-»- K
i <
^ ^
>s
V)
t
fifEK
3
cr
•—
Oi
QJE*
4-
c
^1
3
V
v
III-5
-------
o
UJ
o o
tj •—
LU
_J
CO
L.
O
at
o
c
4J O
t— •»•
J3 4^
•r- *O
VI i-
VI 4-1
•«- C
E 4>
i- U
4) C
Cu 0
0
u
41
O
a.
^
*•• +J
E U
4) *K
0 0
*~
C
o
4J
C» fQ
t/O 4)
a.
^
O 41
•*• 4->
VI ^
>i)4^
a.
,_
ia
u
j™
o
cvi
l
10
U
o
*""
•o
f**
o
—
•o
o
o
"a.
5
»••«
-C
CO
^^
CO
E
01
E
CO
r-l
i
u
I
VI
>)
VI
•*•
•a
2
o-
41
ffm
«^»
^
*J
«^»
c
o
a.
•^
«c
CNJ
I
IQ
o
0
•a
3
o-
i
i "^
Q
^^ R
* B
M 5
^1W
— >>
C C
41 ^
E O 4>
»- u -a
T3 O i-
r- •— L.
>|JC 0
^ 0 t—
< O <_)
CVI
JC
CO
con
g ^^
a. en
Ct E
CSJ tjft
tt
o •—
£ o
VI
V)
J
•o
"y
cr
*M»
O
_f
o
r—
«J^
^-»
9^
^-
<
CVI
^
CO
GOTO
*«^ c
g ««^
a. en
a. E
»-( <*»
t
|Q
o
^~
t
•o
3
or
41
n^»
u
a
r*
O
r-~
9b|
^—
<
t-H
^
CO
J^ "^^^
con
^ e
E-^
o. o^
Q- E
vn co
tvi .-«
4-
IQ
|^
JC
u
^^»
CO
E
3
«^—
C
CVI
1
t
p—
(O
u
0
*""
•o
^•B
o
VI
0)
•a
**"
tw
0
3
fW
*4_
«•••
ea
E
3
•V*
e
CVi
1
i
fO
u
o
*X3
*^*
^**
o
VI
41
^^
•*—
**-
*—"
3
in
^^
ea
E
3
•^
c
CVI
i
+
*o
u
o
*~
•o
^m
O
VI
41
4^
•O
ft
u
10
CJ
•^
c
CVI
1
t
15
• o
*""
•*•
•o i
^•B
0
I/I
j
CJ
^J
4Q
<•
0
L.
"C !
CJ '
E
3
^•«
C
111-6
-------
O «-"
«•- X
UJ UJ
_J O
CD
u
o
5
o
4) O
.O •*->
vi u
VI 4->
Is S
C w
^ c
a. o
u
o
V
o
a.
-£
25
12
o
.fcl
I/) V
c
a.
•8
U 4)
*^ik ^j
V> 10
*•» **
O.
u
u
«s
<*-
3
O
P
E
c
CO
JZ
CO
i
CL
^rt
t
«9
U
O
•f
^
g
cr
V
c
e
fV
CO
^6
-- — _
CT>
E
V-O
«
o
<• 4
« •*
^1 ^
|i
VI
•o
^1^
0
w
a
c
1
III-7
-------
o o
«_> «->
^^^ 5^
o
r* t—
I
CO
o
s*
CJ
c
vt u.
VI *J
••- c.
E &)
J- O
E 'u
>j ^J
-C CO
0.
IQ
u
C
w
JZ
<^j
,
•)
VI
J
VI
(0
Ol
1
10
o
•a
E
IT)
O
*
O
1
U
i
t«
>>)
VI
i
VI
HJ
Ol
c
«^-
VI
u
<:
i— <
g™
CO
^^
CO
E
Ol
E
in
h)
VI
*
+
•f
•a
^v
o
VI
u
c
VI
l_
f^
1
i
u
i
y,
>^
V)
t
•o
^•B
o
4-t
0
>)
VI
t
•o
•«>B
^»
o
VI
u
o
^~
^3
«9
L
^--_r"
IO
1
u
c
V)
!•»
<
rH
I
J
u
1
*^
>l^
VI
t
•a
^^
o
VI
*->
i0
O
•5
k
•^••^
E:
t
u
"c
V
VI
u
r— )
f*
CO
**m^
PO
£
*•*•*,
a>
E
^1^
•
O
* •+•
•— o
o S
^" tn
>i^
VI
$
•a
r~*
O
V»
•a
«^»
^
o
c
4)
V»
i_
t— <
1
H
•— o
IQ -^
u E
o ai
VI
>,
VI
+
•a
^»
o
VI
41
^JJ
*^»
•4-
3
VI
a
u
c
VI
u
«— 1
1
H
f0 *^>
o S
VI
>,
VI
4-
4-
•o
^»
O
VI
41
•o
K
O
^J
C
a.
u
c
4)
VI
u
^^
^
CO
CO
E
^^
E
l^>
•
0
It
•— u
u E
o 4J
vt
X,
VI
I
^g
•^
^M
0
VI
4>
•o
u
•O
•^
u
u
c
41
VI
u
I— t
i
1
.e
CO
CO
E
CT*
E
in
«
O
i!
•— u
o i
V)
>^
VI
4-
•a
P—
0
VI
•o
^_
O
f
U
•»••
<> >
u
c
4)
VI
l_
III-8
-------
o u
o —
"-" as:
ac.
UJ UJ
—i o
j^
o
CT>
4)
O
C
O) O
r~~ ••••
.0 4J
•»- •*•»
vi "0
^^ 4^
.C CO
o.
— —
1
o
•^H
.c
CO
^^
c^
E
CD
tO
CM
+ •*•
•*• +
-0
*"* tn
X,
v>
t
^Q
»^
)»•
o
4)
•o
K
O
"u
t-
u
•f»
c
4)
VI
t_
*
•^•4
^^
CO
^^
^o
E
i"
IT)
*
0
J t
^— o
U E
O &)
VI
V)
t
•^3
»^*
*""•
O
<*_
3
"^
h-
U
•t—
C
4)
VI
t.
**
CVJ
s.
CO
^•^
ro
E
cn
to
•
0
•f
-*•
^
U
0
*~
•f
•a
•^
f
o
V)
E
«*—
t-
lv
VI
t-
«^—
3
cr
f*m
4)
C
4)
P^
C
4)
CQ
tvi
1
t
«3
U
O
*~
•f
•a
«^«
*••
o
VI
41
C
O
£
_c*
ex
o
Kl
c
4)
ca
•^H
r~
CO
CO
E
CD
E
*
-f
t
V-
o
o
4-
^
•»-•
3
cr
f«»
4)
•o
t-
O
f
0
PMB
>^
O
c
ca
•»«^
JC
CO
CO
E
CD
E
u,
-f
t
1C
U
O
^~
•*•
•t-
^5
•«H
^1^
o
VI
4)
b
u
4)
O.
^•M
^^
o
(M
c
4)
ca
CM
i
•*•
•*• +
^ u
u E
O QJ
VI
VI
t
«««
3
cr
^B
^
o
o
u
pHIB
^
M
c
4)
CQ
CM
1
t
to
(^
O
*~
t
•a
3
cr
riw
4)
*J
O
N
C
41
CO
^•M
^
f^
C
41
CO
CM
1
+
r-
0
o
r^
t
-a
3
cr
p!^
4)
-a
«*—
o
^p*
>^
N
C
41
CQ
1
C\J CX
r-
CO
d.
a.
•f
t
—
u
o
r~
*
•^
3
CT
^^
4)
•o
t.
O
g
^^
^^
IM
C
V
CO
cc
f*^
g
*^^
C"
w~)
fs*
,
0
4.
4-
—
U
c
*~
^
••
f
\
\
-------
o u
o •—
Q£
LU
O
u
0
$
"•9
e
»
u
4)
O
0.
^
*•" ' ^^
| 0
-------
O
UJ
X
o
CO
<
X,
o
w l_
VI 4^
•»- C
E fl}
1- U
0) C
0. 0
u
0)
o
o.
^
1 1— *-»
a; K
0 0
*~
o
c «
•»- u
_^ -*— *
^K 4»
to v
C
OJ
Q.
U *•
**" 4^
VI «0
>^4>J
.COO
Q_
ia
u
i
5
•
oo
-C
CO
•**^,
Q.
ex
in
O
•
4- -4-
4- 4-
*- 0
Q •«•*
o £
«/i
>»)
VI
4-
•o
^•M
0
V)
w
c
o
V
JC
ex
o
•4VI
V
u
o
-C
0
<\J
J_
CO
^Xfc
PO
J=
E
in
*
tt
- u
4O •^>
O
VI
t>
C
o
JJ
o
T^
f*
CO
ex
ex
•
3:
«— o
0 "g
o 33
^~ t/i
>•)
VI
4-
4-
«»- C
3 •»-
•^ 3
f^ t^*
^
e
1
L.
CD
•v-4
f-
CO
1
ex
m
4-
0
U
O
*~
»•.
TS
*3
er
^•»
^|
• c
«*•
s
*>•
3
CD
C«4
^j
CO
1
ex
in
•
3
iQ
u
o
*~
t
-o
3
^M
^^
e
ex
lO
u
^|
x
*>>
3
CO
cu
1
J
IQ
o
0
^"
J
,3
3
cr
f""
•o
*^
u
^^
u •
.k,
3
«n .
•«MH
.c
CO
**E
1*
*"*
tJ
»- 0
fl3 *^»
0 1
t/l
"*
4-
•^
^^
0
0
i
VI
u
'' ^C
§
"5"
*«
. 0
VH
1
4-
*- O
<-> E
o 53
*~" ^J
^
VI
^M
fmm
O
VI
O
£
C
VI
u
^c
E
*7™
I
u
*«»
T— (
c
*i
o
^^
"i
I*
in
Jj
<-
^- "5
53 o
VI
VI
t
,^
^H
O
VI
C?i
'ft1"
"C1*
©
"O
L.
^
1
4J
C
U
O
^
0
Ili-il
-------
X
o
LU UJ
_l O
03
o
o>
ssible
tration
eg
t- w
*» e
0. O
X
w
8
o
a.
^
f^ ^j
§2
E
o 53
" ft
VI
t
XI
"3
cr
o
J£
CJ
•^
s
JC
i
•f +
— VJ
10 *fM
u e
o 0
r** +A
VI
I/I
•f
XI
^KI
o
3C
0
ex
§
U)
tt
— u
'O *^
u E
o 53
VI
VI
%
XI
3
cr
9)
4-1
e
ex
z
fc
ex
ex
o
u
CVI
1
% i
- u
fQ ^»
0 g
o 53
"ft
VI
XI
^•v
o
VI
VI
o
ex
I
o
1
%
10
u
o
$
x»
3
cr
-------
x
o
Of
UJ UJ
_J O
CD
u
o
0
o
e
4) O
S"5
VI U
V) 4-1
'i £
i- U
E^J
t» *f" '
O) K
00
H-
O
C «3
i- U
CO 4)
C
4>
a.
~
U 4)
•f~ 4J
v> *
>>**
.c U1
a.
_
*4f
U
«*•
£
°
OJ
s
1
0.
CM
tt
»•" U
IQ •»•
o 0
f*** ^^
V)
£
TJ
9
cr
D
*o
*
•o
^*
t
«^M
9
cr
4)
£
§
0
tM
CO
CO
E
E*
t— <
0
It
•— O
•o •»-
u 6
o
c
4)
{^
o
c
0
•*•*
CO
1
CL
in
O
It
•- u
'O *f*
0 §
"""ft
V)
*
^
*^*
"o
VI
4)
T3
•f"
c
V-
co
c
4)
en
o
c
u
*-"
•^
JC
m co
2m
tt
•— o
o i
"U
VI
-f
V)
4)
•a
4
o
u
c
V
en
o
c
«0
0
fM
CO
i
o.
o
m
t +
«— v>
^n .^M
U E
o «D
^™ ^^
VI
VI
^
,^k
3
er
*o
c
1C
K
4)
0
£,
U
(M
CO
a.
o
m
^
•— o
•a •»-
u E
o S
"ft
VI
+
^M
3
er
V
c
o
c
>
K
(•
O
"^
O
CM
cc
"H
a.
a.
o
•*• •*
|M .,
U
©
^
.^
•V*
*0
v^
1
(
1
-
1
-------
o
CJ
CO
<
X
o
UJ
a
o
en
41
•O
e
4) o
JO 4->
VI L.
•»- C
E 4)
i. U
41 C
CL o
o
41
O
CL.
.-£
"»<
a o
t—
o
c <«
•«- u
J* *•»
>!
VI
J
•o
er
•••>
^•B*
o
o
u
<
c*
e
o
41
*^B>
a
CM
1
tt
>— o
^
VI
^
VI
lO
en
41
e
<*y
u
o
^»
o
CM
1
ft
f U
o 0
>>,
VI
^
•o
^1
0
^J
^5
u
0
CM
1
+ •*•
^ u
o S
>,
VI
+
•o
)Z
0
VI
«~
c
O
u
•#••
a
CM
1
$
i«
o
o
+
•o
|H
o
I/I
41
C
o
JC
u
*w*
a
CM
j—
CO
•"ts^
E
0.
Q.
O
O
o
•"•
,
u
1
VI
VI
$
VI
*Q
CO
at
c
2
jj
0)
k
3
O
>*-
•o
! °
o
J=
o
•*"
a
CM
t"
CO
E
Q.
a.
in
tj
•— o
o 53
X,
VI
+
•o
•^
p—
u
-,
VI
•f
•o
«^»
p^
41
c
a.
o
a.
o
u
o
u
•»~
0
CM
i
i
,,
— U
o H
>»,
l/l
•*•
"O
cr
^•»
4>
C
4J
CL
O
CL
O
o
*•••»
u
•*~
a
111-14
-------
ce
UJ LU
o
O)
•»- C
E 01
V. U
4> C
a. o
u
g
"o
a.
~£
§5
^U K
0 0
*~
c
o
c *)
W1
$
'O
•^
3
cr
•^
i
0
u
- Q.
O
u
0
*•"
JS1
u
Q
4)
D
ex
o
ex
o
o
f^
J£ Q)
u e
••- *
o a
{NJ
J=
J= 00
00 ^v
CX en
f"H
• «— 4
t
0
1
VI
>)
"^
•4.
•o
«^»
J3
cr
•r""
*
o
0
f""*
«c
^)
«^>
a
CM
jj
CO
1
ex
to
J
^5
|Q
c
ex
O
O
$^
U
o
<\jj
1
t
^>
u
o
-
^3
<*^> :
fM>
O
I/I
ft)
c
•^
s
o
"O
JC
4J
4)
•••»
o
(Nl
^
CO
1
ex
w?
CJ
t
^-
u
o
*~
$
«^"
•J
cr
»^*
V
c
i
j^
4,1
V
o
CW
i
+
u
1
VI
>«l
IS)
•f»
3
Cr
•*^
r~
o
^w
^D
a>
*>,
JJJ
4-»
^
^•~
o
<\j
JC
CO
1
ex
1-1
t
—
u
o
^^
3
cr
*^*
V
e
i
•*M
U
c
V
*>>
JC
V
•p*
a
tNJ
1
•4-
19
U
O
^~
•f
•*•
•o
*^»
3
cr
•*•*
fHM
^^
J=
Ul
* »
01
^j
*c
IQ
•«C
Cu
*>>4^
JC «
a; u
«^» o
GUI
<\j
j=
GO
r^ i*^
COnO
CX cn
Q. E
O CO
t— ( •— 1
•*•
t
•a
o
o
„.
•o
X 3
•— cr
"o ^-
^
c
1
*>»
J^J
at
*^»
o
CVI
JC
CO
f"T^
a. E
a.
y^
tn CM
-f -f
o •—
i o
V)
>^
«/l
•o
^% J
f— cr
O r—
4)
C
pw
«^»
e
*>>
JZ
•o
1
y^
«
X
CNJ
jjj
CO
o.
o.
^
1
•Q
u
o
*~~
•4-
•o
3
QT
«^M
4)
•O
V*_
3
*>>
^M1
^
£
•^-
a
CM
JZ
CO
o.
CL
O
4 -f
i— U
u "e
0 4
^~ *
>
V
^
^^
3
cr
^.•T^,
4)
e
X
o
^5
1
O
4)
C
AQ
M
c
c
-------
o
UJ
LU
—I
oa
o
M
X
o
UJ
O
o
c
O) O
^J 4^
°^"
I- U
Ol C
a. o
o
u
r^ 4.J
VI
>•>
«/l
^>
4*
•*^
*o
3
CP
•T™1
0
f— t
CO
CO
E
en
t—4
•
•f
$
y
*^»
i
^jt
VI
V)
^
^
•o
•«-•
3
cr
*^-
^»
4)
C
O
4-1
O
^™-
13
^l
^•B
O
CNJ
I
*t
•— u
o E
O w
«>•• 4^
v>
v>
•f
•f
c
0
u
3
•^
a
>
VI
4»
+
O.
OQ
z
o
CM
1
•*•
U
«
I/I
4»
J^
4J)
^•^
E
>— i
«
O
I
U
§
4-1
V)
VI
4^
4»
•o
F~"
o
VI
e
<+-
F*»
3
VI
O
•a
c
UJ
t
1C
u
0
p^
P"»
10
f^
^f
a
•o
c
UJ
CM
OO
J30
00 E
"cl^1
^^
tn<~1
•f +
•— o
U c
o 83
^"* 4^
VI
>•,
V)
4»
J^
T3
«^»
3
cr
^~
c
u
•a
JC
o
u
*•-•
j^
u
Q.
UJ
1
t
U
8
^i
<«
VI
^
^»
^
•^
3
cr
•^-
*"
c
o
^
^ «
UJ
CM
CO
^^^
00 E
E O"5
CL E
CL.
08
O T
t
*Q
O
P""
^
^
f
•^3
•^
3
cr
•"
V
4»J
IO
,1^
0)
u
*"•
>^
^^
^>
UJ
111-16
-------
UJ UJ
_j a
u
o
1 »
•o
c
4) O
J3 **
•*• M0
VI t-
VI *•»
••- C
e -|
to
t
•^B
3
cr
c
^^
A3
*•••
^n
u
y
4^
*>>
JC
UJ
CM
JC
CO
a.
a.
o
o
»— 4
tt
•— o
to ^~
o 25
•— •*->
V)
>•>
V)
t
•o
3
cr
&J
c
V
IM
e
4J
00
*>,
jr
UJ
CM
e-
CO
c
Q.
Q.
O
O
O
*"•
t
O)
10 — -
U jQ
0 *J
r- VI
O
**"
t
«^»
J5
CT
4>
^3
•«»*
I_
O
^~
JC
o
*>,
JC
UJ
CM
1
,
4>
*O 'fm
U J3
0 *J
r—
O
<*-
$ •'
VI
•
t_>
*•*
UJ
CVI
1
+
0
»^~
g
+J
V)
>>)
tn
t
•o
^»
3
cr
c
«^»
u
•o
^f
JC
o
c
«o
^^
o
4}
c
4>
">,
JC
UJ
CM
c
c
JC
co tn
11
ex a.
0 0
CM U1
tt
•— u
o S
*^ ^*
VI
>^
VI
t
•o
•^*
3
er
4)
•o
•^
u
^^»
o
41
c
41
*>,
JC
UJ
CM
C
JC U-)
00 ->>.
Cv CX
0.
o
0 0
"* ^
JJ
*— O
fQ *^"
0 S
»~ 4-»
VI
>s
1/1
"-*•
*^
3
cr
4)
*«•»
u
o
aCt
u
^^
o
^
c
4)
*>,
•C
UJ
CM
1
u
*^H>
g
•4-1
V)
^
v>
t
•^
3
cr
4)
10
4)
*>,
JC
UJ
CM
JC
00
***^
a.
a.
o
o
*^
•f H-
U •—
*^^ *O
S o
*J *—
V)
>•)
V)
t
•»^
3
er
JC
4)
O
C
o
x:
r>^
0
3*% *•*
^•^ *o
CD 4J
V
V O
C *t
4)
1>> 4>
JC JC
UJ UJ
CM
f~
00
ex
ex
vn
CM
u
«^v
§
*J
V)
>^
v>
t
•o
3
cr
JC
4)
O
C
jr
^•*
Q
y
jt^
^"*
CO
m
c
4J
>> 4)
JC JC
UJ UJ
I
CM
JC
eo
ex
ex
O
in
1
_
f^
u
0
^"
^.
•o
3
cr
4)
•a
K
O
0}
C
4)
*>>
JC
UJ
CM
t
1
JC
cc
•^^v^
ex
ex
O
o
'T
-*•
-f
UJ
u
o
^"*
*
•o
•*•
3
cr
u
4)
jj^
^j
UJ
*>,
JC
UJ
r ; T i •
1 i i ~ i. i
-------
X
o
k.
o
4*
U
41 0
f <«
«/» 4.
f C
6 41
k. u
4> e
a. o
u
g
S
a.
•sS
e"o
u ••-
4) X
0 0
*~
e «o
f~ U
CO 4)
g
a.
15
U 4>
•»- •*••
yi ^
^t ^ji
JC CO
u
8
JJJ
o
CNJ
co
^^
co
E
m
r-t
U
U £
O +J
f™ ' ^
^^
V)
•f
^3
•^
p*"
o
wl
i
j0
i.
U.
CNJ
1
t
U
o
^™
1
^o
•^
**•
o
VI
41
X
o
i.
1
u
k.
u
41
**•
CSJ
JC
GO
CO
E
1
-«
t
*
•a
4^B
3
u
T
u
4>
U.
CSJ
1
,
U
0
,
^3
•p*
fm
o
W)
41
JQ
«*-
f*
CO
1^
o'
k.
u
41
u.
CM
1
t
15
u
0
1
^g
«p«
fMM
O
M
41
X
O
^3
^»
VI
o
u.
k.
41
U.
(VI
.
1
,
15
u
o
1
^g
•^M
^•^
o
«*
41
•fM
4^
^•B
CO
^}
3
O
k.
k.
41
U.
CS!
|
+
•— e
•O 4)
U 91
O k.
^w
r—
10
i
«^
3
tr
^^
Ifm:
o
JC
^
«^»
u.
ff— <
g
CL
^^
J
15
u
o
^w
J
4^
15
E
O
U.
CSJ
JC
00
1
a.
wo
1
u
0
jj:
73
3
^^
^B
73
JQ
U
"e
0
u_
CSJ
JC
00
^v.^
E
CL
LO
i
<0
u
o
pmm
^
•^M
3
a-
^^
«s
k.
t^.
k.
3
U.
MI-IS
-------
o o
*^ ^M
»-- X
o
ee.
UJ
o
u
o
id
4) 0
Ho •*»
«^» m
VI i.
VI •*->
«•- c
E 4>
U U
4) C
CL. O
U
U
ft)
O
0.
«— •*•» •
ft) K
0 0
t—
C!
0
-M
C «0
•»- u
(/I 4)
4)
0.
,5
U 4)
>^ *•»
VI <0
^> ^^
£ «/>
0.
15
4i
1
J^
o
<\j
i
—
u
0
t
«^»
a
cr
«^
^w
VI
"o
VI
t^
0
CM
1
«*•
IQ
U
O
•^
a
cr
•yv
|M»
^**
X
s,
o
CM
1
t
u
1
&
I/I
t
•o
^MB
Q
VI
e
o
•M
a
o
csi
_^
00
CO
E
o>
E
lA
*
,+
u •—
J, « ^B«»
^* ^^
VI
v>
J-.
'^3
•V
^
Q
v»
^
o
^
u
to
CL.
a:
PW
J^
00
^^
E
o.
a.
O
O
to
+ t
•— u
o S
I/I
VI
t
•a
a
•*••
fM»
4)
C
cx
4)
«XJ
i
*
i— O
«O t-
o cB
VI
VI
t
-o
a
cr
^"»
^•w
f^
O
g
Ou
4)
X
«— •
i
i
u
1
VI
v»
|
•*•
a
cr
*f»
|MW
CL.
UJ
ac
CVI
1
tt
s^
o £
"s,
VI
t
T3
a
cr
^H>
4U
e
u
o
JQ
K
4)
rvi
i
|,
•— 0
*O -w-
0 §
VI
V)
t
•o
fi*»
o
VI
4)
C
I
•o
ft)
£
^M
^^
JC
«)
§
K
ft)
CM
JC
00
g
Q.
Q.
O
O
in
+
i
— 0
o S
VI
V)
T3
a
cr
^"™
4)
C
«O
K
4)
CVI
1
It
«
O
0
t
•o
a
cr
f**
r*.
O
c
•9
X
4)
3=
Cw
j^
cc
j^j '» j
eo E
ie"o
Q. E
Q.
in cv
cv »—
•4-
«3 -
U |
• o <
*~ "-
t
*«•»
a
cr
^"»
^•B
e
3
u
^
(
f
1
:
111-19
-------
k,
I
•M
O
e
4) O
J3 -•-»
VI <-
VI •*>
•*- e
ECU
U
^y ^»
a. o
0
u
g
o
a.
^£
* *K
H-
c
O
••- U
«/l 41
e
4)
a.
-
U 41
•^ ^^
yi *9
^^ ^^
JM» ^^
a.
49
u
i
J3
^J
-
.c
oo
1
Q.
i— 1
J,
s"
o 0
VI
*
^
•fi*
3
«^»
^^
Cl
e
«^»
M
lO
U
"gj
3C
^
_
1
o.
to
l+
3"
o S
VI
*
^
«^*
3
cr
«^»
^w
•^
^M»
^
U
O
J~
y
Q
iw
"5,
z
^
__
1
o.
CO
{*
•— o
O £
o 6
VI
w
^
«^»
3
^^
•#*•
fMB
Ty
^M
^
U
U
o
3
P"*
I*.
O
1^,
5
-•
1
J
u
i
VI
*
i
VI
-------
UJ
00
o
5
<«
tj
c
0) O
VI U
•*- c
E V
C u
0. 0
U
«u
o
0.
»•" 4J
^ "f^
s"i
*~
o
c «
— U
I/I QJ
c
0.
*> 4V
a.
U
6
JC
^J
(SI
1
l+
•o •*-
o i
ft
"*
$
"3
cr
«*«•
"5,
XI
V)
2
^
5^
^^
9
49
O
VI
*"*
(SI
1
J+
U g
o 53
ft
VI
+
•rs
*9
^
3
u
<
u
L»
^i|
4J
9
JO
O
V)
fc—
(SI
00
1
Q.
^n
(SI
tt
0 S
ft
*"
t
"5
a-
«^»
e
• o
u
o
CL
O
1 *
(SI
I
J +
10 —
O V
ft
"*
^
2
pM
0
VI
"u
o
o
^^
o
^1
JC
JC
a.
o
""
(SI
§
^^
o.
o
^n
(SI
0 S
ft
"*
t
9
o-
**
4-*
o
*
^^
CL
0
k.
o.
o
1— 1
(Si
^g
00
i
a.
in
tt
LU
^^
O.
O
u
CL
O
VI
*H
E
^O
•
+ J
IS i2
0 S
"ft
VI
+
5
pM
o
V)
D
4>J
«
i
VI
U
•o
S
(SI
1
tt
*
-------
UJ
_J
GO
ai
UJ
o
en
*
c
4) O
ja •«->
f tO
VI U
VI *-»
•»- c
E ^
^ O
4) C
0. O
U
4)
O
0.
^
I— 4-»
•0 •»-
E U
Is
*~
0
4-*
t/> 41
41
a.
»**
J=
8
2,
VI
u
3
J=
4J
i
^3
o
^J
Q.
U
I.
0)
CM
j-
oo
oo
E
en
E
f**4
o
*
,1
- u
fO *F"
U E
o O
2,
VI
^3
*v*
^™ >
o
VI
41
•o
C
2,
^J
u
•^
u
u
u
X
CM
JC
00
m
E
O>
E
U)
O
•
*i
•— 0
"9 *^~
o S
ft
VI
•a
«|M»
!*••
O
VI
ti
•%
J-
2C
U
•^
u
u
£
CM
J=
00
i
a.
f-H
+•
•— u
o i
VI
VI
•^
3
cr
^^
4)
^*
U
4^
c
o
>%
1^
jj
J=
4^
4)
CM
J=
00
^
Q.
a.
o
•"•
1:
— u
*« ^-
ft
VI
t
•*•
s
*^—
^1^
4)
|Q
*>>
^
^
^c
•r
j=
a*
3E
CM
JZ
CO
^
a.
o.
o
LO
+ t
•— 0
*
o £
VI
VI
•^
3
cr
^^
,
*o
J=
o
^£
*^
^^
C
^
*r*
^
^^
«
^H
f*
CO
E
Q.
a.
0
CM
J
|0
U
O
•f
*O VI
•»• >
V.
t
•o
3
cr
i«^
4;
•a
V.
o
j=
o
4J
C
41
•T
JZ
^j
41
111-22
-------
03
a:
UJ
o
o
en
o>
us
o
c
4) O
J3 4->
•H- (O
V) U.
VI 4J
••- C
E 4f
U U
4) C
a. o
u
g
o
a.
~2
4)
C
4)
O.
-
U *V
f- 4-1
15
o.
^M
4-
4- 4-
*- U
u "E
O 53
^•- 4»J
VI
VI
t
,
•^
o
cr
r»-
4)
e
o
£
JC
UJ
pv
^)
JZ
4J
2
IVI
t^
00
"E
a.
a.
g
«— i
4- -*•
•— U
U E
o 45
^•- 4Jt
VI
V>
4-
^
•^
3
cr
^»
o
4}
**
•^
3
O
V)
^~>
9^
JM
4^
£
fSJ
J=
00
1
a.
o
r— *
J$
UJ •«•
o i
^™" 4^
V)
>•>
^
i
•3
en
e
ex
u
1
f" «•
)B^
•C
4«J
X
tvj
J£
CO
*E
O.
ex
o
o
*~*
4-
r-
u
0
^•*
•*••
3
cr
pw
4)
•O
*>»
u
z
p^»
)b^
f£
4-*
4)
Z
^H
ro
E
en
O
O
CNJ
1
u
i
•4^
4ri
>^
1/1
•j
»^
3
cr
IM
e
o
|
«
CL.
^"
>^
_f^
4^
£
ru
i
t
^- o
o "p
O 4)
^"" 4^
VI
*"
4-
T5
•**•
o
Vt
4*
4J
JQ
U
IQ
u
•0
K
41
CU
4
tj
_ u
o C
«— ' -4J
>,
V>
4-
^
•^
3
cr
**"
^m
4)
e
o
4)
«
O
U
o
^»
J£
u
o
c
£
(VI
JC
CO
^^
g
p^
ex
o
o
o
*"*
4-
^^^
4)
F— 4-1 U
*o •»-•»-
OU3 E
o 4J> 4;
r- V) 4->
O VI
U >)
>*- VI
4-
•a
3
cr
f-»
i
x:
g
K
o
o
u
o
4=
u
0
c
^-4
J=
00
ex
ex
o
*^
-*>
^.
u
o
^**
4-
Jg
en
4)
c
1
***»
JC
4J
4*
O
C
rw
i
*
-f
4 4
^ U
U E
O -,
VI
4.
4-
•*#
^
•^
3
cr
r~
41
e
P1*
0
JC
Q.
IM
*
111-23
-------
O
Ul
9
O U
O "-•
—- X
o
l_
o
on
O
C
4) O
5 "«
VI ^
-r- C
E 4)
L. U
4) e
0. O
cj
,
"« f
U**"»
-*~-
0 0
H-
O
e «w
t/1 4)
C
41
O»
—
,
X
1
E
CM
1
£ t
*— o
II
I/I
I/I
t
'O
^•B
o
I
10
z
CM
.C
03
e
E
ro
4-
•— 0
11
VI
VI
.*
•o
3
cr
r^
•o
4)
|Q
z
CM
jr
CO
1
Cv
8
•-H
t
,_
U
o
$
•o
3
o-
^He
a*
4^^
*O
^
41
u
1
1
c
CM
j.
CO
-C ^^
CO")
a. en
a.£
O O
ft W1
t t
f. o
0 »
VI
VI
+
^5
^-»
^M
O
VI
41
C
41
f**
*
4-1
a.
^—
0)
^
4-1
41
^
4^
•JT
4J
1
C
CM
|
+
t
„
U
O
+
•o
«»^
3
or
*^>
^-"
•^
^^
1^)
L.
^j
i^^
rr
3
jQ
1
C
CM
JZ
CO
Q.
Q.
O
in
t 4-
f O
u e
o 33
VI
>i
V)
4-
H^
3
o-
•^
^—
"o
^2
O
u
r^
^(
fT
3
1
C
CM
1
+
i
„
. u
o
t
•o
«^»
3
or
•^
^"
-o
•^
JT
«u
^3
^i»
•e
u
3
1
C
111-24
-------
O «-i
O <_)
*™' X
^H O
LU
CO
<:
o
cr>
OJ
»o
c
41 O
JQ *J
VI V-
vi 4->
••- C
E 41
U U
4) C
Q. O
U
U
4)
O
n_
^
r * +J
15 5
O) K
0 0
t—
O
C "9
•«- L.
i/i 41
4)
Q.
*««
O 41
•. - 4_>
VI ^
•^i 4^
£"»
f—
M9
o
*
-f *
T— U
*T3 *^
^"^ *J
VI
t/>
$
*^B>
3
o-
"^"
*>.
C
O
L»
IO
o
*4»
^^
U
*^»
z
^^
oo
o.
o.
CM
I
_
IQ
U
0
+
•o
*v^
3
^^
•*•
^3
*fM
U
<.
o
u
• J
/^
z
*^
jC
00
o.
0.
co
CM
I
^"™
«0
u
o
4.
VI
A}
4)
•o
K
O
U
u
4^
•»»
z
CNJ
1
•*•
•t-
~
«0
u
o
•*•
^o
^>
(•^
o
l/t
tJ
u
^
o
"^
u
4»)
**••
z
**H
c
m
LT>
r-1
"e
0.
a.
LD
t
«
u
0
4-
VI
IQ
4)
•o
K
o
o
1
o
L.
^J
•^
z
CM
_c
oo
"e'-^
o. o>
0. E
^H ur>
* -f
-*• 4-
•— o
*"~ t/1
>>,
v>
•+•
•*•
*^~
3
CT
«^»
i
tNJ OJ
1
t
iQ
o
O
^~
t
•o
3
cr
4)
^
C
4)
N
4)
.0
O
i.
«^»
z
•o
i.
o
f
^__J
c
41
O
U
^pv
z
JC
oo
ro
E
cn
E
CVJ
tt
^9 •«*•
O U
*"* ^A
>,
VI
-f
•o
3
CT
4>
C
t
4)
^
cr
o
V.
•^B
Z
1
C\J
f
CO
Q.
o.
t— 4
•
tt
•— o
O V
4/1
v>
+
wt
0.
41
C
o
N
0
C\J
^"
CO
Q.
Q.
CM
i
*o
u
o
•
*
^
KJ
0.
41
•o
K
o
3
O
k.
•*•
Z
-Vj
i
«*•
IQ
U
o
*~
J
•o
3
cr
4J
C
C
o
111-25
-------
O O
^-. X
o
UJ
O
u
Q
Ol
41
4-*
e
u o
VI L.
VI *•»
f~ C
E 01
U U
41 c
o. o
V
**" ^J1
VI «O
J= (/I
ex.
!«•
U
1
o
eg
1
1
<9
O
£
•o
3
cr
pM
. ,1
I
JS
a.
^^
^^
i
cu
1^^
a.
a.
i
•— o
*•> £
o O
ft
1/1
t
•o
3
cr
#M»
^M
e
o
u
^M
^k
a.
o
u
o.
e
eg
i
,,
•- u
t
VI
t
•o
"5
cr
•*•»
^*
«;
c
*4l
^^
>^
K
O
CNJ
jg
1
0.
t— (
t:
— 0
<« f-
o 5
VI
VI
+
^B
fM»
0
VI
«
c
*e
o
^J
«^»
e
i
«Q
U
a.
eg
,+
— 0
40 **^
o e
o «
ft
VI
$
•o
3
cr
•»••
^»
^^
JQ
C
^
^J
c
a.
eg
JZ
03
i
a.
t J
— 0
40 •*"
ss
ft
VI
4,
t
•o
3
cr
•^
*^
C
<0
^^
a.
(O
u
I
*>>
|
O
u
o
f**
^J
o
u
a.
eg
i
+
___
lO
u
o
*
5
3
or
•^
•"•
•a
i.
O
JC
«!
e
s
jQ
i.
40
u
!*•
o
c
a.
eg
i
4, 4=
f— O
«v
ft)
^c
u
3
O
u
V
E
*•*
O
c
JC
CL
111-26
-------
o o
2, 5
o
»-l »—
I
cc
LU LU
_J O
CO
o
en
%
o
c
HI O
JO -4J
4/1 t.
I/) *->
•»- c
6 ft)
t- u
o> c
ex, o
u
0)
o
CL.
^
^— **
15
0) X
Q 0 „
H-
O
e
00 ft)
«u
Q_
lie
u n ^j
4= VO
0.
*
f^
(Q
u
•^
1
o
«— 1
f™
CO
^E
CX
ex
•
j
•O
U
O
•f
VI
IQ
en
*»
c
0)
en
VI
o
JC
O.
»-4
4
J,
»— O
o £
V)
>•,
VI
+
•o
«^H
r-»
O
VI
**"
o
**"»
>•>
~l 1"
I/I
3
0
0
CX
VI
o
0.
4U
^J
^i~
J^
*
CM
1
it
«— o
.,
VI
t
«HP»
3
CT
«^B
F**
4)
•o
"jD
O
JC
u
V.
VI
3
O
0
JC
ex
VI
Q
J^
CL.
CM
4
•O
U
o
j£
•o
3
CT
f^
V.
*»
I/I
LU
1
">,
JC
^J
V
••P1*
o
1
«^»
^
u
*•**
|Q
.jC
^4
JC
CL.
CM
g*
oo
^^^
H
CX
t— 1
^
»— o
»— *J
VI
VI
•*•
^g
<^B
i*—
O
^
4^
^3
«^
u
•a
J^
c
u
^>»
. to
JC
+*
JC
ex.
CM
1
,,
^- «J
^
4^B
C
VI
*
I
VI
VI
•a
^-*
o
ex.
CM
1
•f
_
•e
0
o
^.
TJ
f~
O
I/I
**
40
C
4O
en
c
i
4U
CL.
§
^M
VI
I/I
«a
^j
o
ex.
i
«M
I
1
CO
"^..^
E
CX
ex
o
o
O
**"
jj:
VI
10
en
eg
c
40
ex
o
ex.
111-27
-------
Ul
H- I-
ac >— •
o u
O '-»
»-^ x
o
»^ 3G
01
ua tu
—j Q
u
i-
*j
Isslble
ntratlon
e 41
a. o
u
u
g
e
OL
^
^^ ^rf
BO
22
H-
O
C «
-* 4-*
V) 41
41
Q.
*«8
U 4)
•*- 4-»
jC
U
a.
o
u
o.
rsj
i
1
^_
^o
u
0
«^»
s
cr
*~
41
j?
tt
•a
e
o
"a.
o
k
Q.
CM
S
I
a.
o
$
^
•e
u
0
•o
•^
3
cr
^
•a
•3
i^£
u
C
o
"5.
o
u
a.
CVI
1
i
^
IQ
u
o
*
•a
4«M
3
er
*~
•o
^
>i
i
^^
u
C
o
"g^
o
u
a.
esi
S
i
Q.
1
t
_
|Q
U
O
•a
"S
^
«
4-*
4t£
41
O
**
•JT
a.
0
u
G_
(VI
1
|t
•— u
f*
3
*™
^|
e
i
•TT
ex
0
u
o.
(VI
i
a.
8
o
•f
>MI1
IQ
U
o
1
ft
^9
41
C
•T"
a.
0
u
a.
•
S
1
o
o
t
_
1Q
u
o
•a
3
cr
r~
41
•o
O
41
g
•T"-
Q.
O
U
a-
(VI
•«N.
i
O.
S
t-4
j +
*-> 0
«a •»-
ft
**
•**
3
cr
*~
41
C
41
"^
X
1
a.
CVI
1
C
p— O) O
0 ^y ^^^
U U E
3 dj 53
« ft
— V,
t
f*
3
cr
*"
^^
e
i_
JC
•*J
41
5">
a.
CSJ
1
+> +
<••»
C
F- 4J U
0 ^Jl *v">
U U E
o 41 53
•5 ft
*— • V*
*
•o
3
cr
'"*
,_^
^^
C
l_
41
5^
a.
"
s
E
I*
t 1
i— 41 0
Q O^ *^"*
U U g
& v >
""""
•o
»~
VI
g
3
U
JC
at
^>
eu
rn-28
-------
UJ LU
_J O
00
o
"to
o
c
V O
JO *J
VI U
VI 4-»
IS
Ij
U
§
o
a.
^
*™ "" ^J
| u
4) X
O O
t—
C
0
C 10
J* «J
IO U
ft)
a.
*«
O V
•^ 4J
V^' *0
5*S 4^
.C 40
a.
*(O
u
C
o
(M
CO
I
o.
^
•— 0
IO *^*
0 g
ft
VI
t
^M
a
o-
—
V
c
5
L
o.
L
JS
«p»
O"
CVI
1
•- 0
fQ •*•
0 g
ft
1/1
+
•o
^**
Q
VI
«
e
"c
^M
S
u e
o e
VI
VI
•f
^o
*v**
pIM
O
Vt
V
c
o
4^»
£
CM
»•*
i
Q.
O
<->*
It
•— O
« —
u E
o «
ft
VI
•*•
-o
^^
o
(A
"o
U
k
o
VI
QC
PJ
1
< +
«— 0
49 ***
0 g
v»
VI
$
•*•
9
er
«
^2»
1
*
gg
ft
VI
+
•o
pi*
o
VI
"JJ"
in >
*j
«- o
V *O
^M IQ
«* QC
-------
O
u
LU
X
o
ce.
UJ
o
t_
o
41
41 0
«S) L.
^ 4J
••- C
E 4)
«- u
41 C
0. 0
u
u
5
o
Cl.
»— 4-1
0 ^*
H-
O
C «
•»- u
CO 41
C
41
0.
-
U 41
•f 4-»
V» *S
>^4J
.C CO
Q.
,_
«9
U
i
^2
°
CM
i
t t
• -
15 •*-
j3 i
«/)
Wl
4.
•o
••»
O
trt
—
41
^B%
v»
CM
1
4- +
^ u
0 §
V)
«/>
4"
•o
•pv>
3
cr
^"*
^j
e
M
«
g
^^
VI
CsJ
i
$
—
u
o
+
^3
•f"
^•B
0
i/)
e
o
*V
cr
•9
u,
*J
C 41
^c ^^
CM
00
CT^
E
O^
E
in
+
tt
^- o
o "E
O W
mum ' *
^^ <^^
g
^|
U
•C
E
3
«p*
T3
O
V>
CSI
1
t
—
o
0
4.
•o
^w»
o
V)
4)
4^
a
y|
«^M
OQ
E
3
^•M
T3
O
V>
CM
1
t +
•— O
o "g
o «
ABM ^.J
^^ 4^
(/I
4-
•™3
••V
•MB
0
VI
4)
»
•o
0
(VI
1
%
15
u
o
t
TO
3
^H»
^^
*>,
|
CL
^3
*>»
3 4)
CO *-
§C
C
•a »—
0 3
VJ VO
CM
1
* t
«£
O E
O V
1/1
4-
V
•a
c
O
u-
5
41
C
4)
M
41
rjQ
•^
U
4)
O
g
3
•o
00
f\j
oo
•*^
CO
E
o>
E
|^*J
r-
O
4-
•o
!•»
O
yt
41
"J^
U
^^
wl
O
O
3
U.
E
^•K
•o
00
f
CM
1
!
15
u
o
4" '
•BK
3
<*•
f^
4)
if
*fr
3
(/I
0
T5
Z
E <
3
or*
"Q
0
111-30
-------
•M
t £
o o
i.
O
u
VI t_
VI 4J
J!
^3
1
o
0.
^
*"* ^J
15
*"
e
e
•^ *»
>ii^j
o.
u
f
JS
°
(VI
1
J
_
10
u
o
t
-o
9
er
^1
u
e
S
g
§j
32
§
•o
~
1
,
^
«
U
o
+
^^
^"»
o
„
Itl
a
oo
^*
_J
I
CVl
1
t
^_
4|
|
4-
<*^
p^
O
V
«
f^
£
^
3IJQ
g
1
S
rvi
i
+ t
«— o
o«
"ft
VI
•f
*5
jg
^h
^L
9C
4^
§*j
<0
XI t—
OO 00
«VJ
1
tt
•— o
«O f
U 6
o v
If,
t/t
+
V*
^—
0
41
^^
. «
**
2E
Sodium
(VI
t
_
|0
|
4-
«^»
f~
O
41
«
H"»
3
|/|
*>»
y
^5
§
t •
t!
»— u
o|
"ft
Ml
4-
^**
^W
O
e
e
t
•«•»
(SJCS4
ss
II
o. o.
gin
rj
^•^
tt
- u
j
40
u
• o
4-
t
VI
o>
4;
ts
5
o
u
3
3
111-31
-------
o
UJ
O O
CJ ^"^
>i^ X
o
CQ
•f.
o
en
c
4) O
^— •*•
J3 4J
I/I t_
VI 4-»
•*- C
E 41
i. U
4) C
0- O
o
o
c
4)
4J
O
Q.
^
^- 4J
41 X
U 0
*"~
C
O
4-1
c «s
Ix 4_>
VI 4)
4)
0.
•O
U 4)
•«- 4J
VI *O
^"1 4^
.C «/>
a.
_
—
i
u
*^»
1
V)
v»
4;
•o
**•
r*^
0
VI
l*J
U^
O
•"
1
•— o
^
^j
3
^
i
4-»
41
1
J I
— 0
fO *^
o 53
vt
VI
^1
T3
3
cr
^^
41
C
^n
g^
j^J
4>
l_
•JJ
t—
CVI
CO
o^
E
Ol
E
•—4
|
T
— — — ' '
u
1
VI
VI
•f
"^
•*—
^.^
o
VI
i
1
E '
3
•^
^*
•—
_2
H-
11-32
-------
o
IU
X
o
a:
UJ UJ
_j o
CO
o
0>
0.
r-
U 4)
V) <0
>^ 4.)
JC ^O
o.
o
i
JC
u
csj
,-
GO
^O
E
E*
^•4
•
O
I
w
•*~
1
If,
>-,
VI
+
T3
•«••
p«»
O
VI
*3
u
^J
*•"
JE
W»
9
O
r^ •
!•)
*
C^
1
•*•
to
u
o
+
«•"•
3
^y
«»—
•1M«
V
c
V
V)
o
JC
Q.
O
•*•
-C
CSJ
^^*
GO
^^
m
E
in
tt
f- O
*-> 5
0 V
v>
>,
VI
t
^y
•^
^—
o
V)
§
u
•V*
H-
(VI
-
1
f—
|Q
U
0
+
^g
••"•
^~
o
VI
^^
•^
c
lO
^al
i^
CJ
1
t
)
v>
+
^•B
9
o-
•*»
^^
Q^
V
9
«•»
»2
CJ
JC
CO
GOTO
-^ E
Q. O1
Q. E
CVJ TT
O «-"
* •
Jt
•— o
o 33
vt
VI
•*•
•a
9
o-
•r-
^^
m
*
*
^- o
o 5
VI
>•)
VI
£
^O
^•B
•IBB
O
w
0)
e
4)
a.
«
X
0
CJ
i
t
«••
i
^
>i
*"
4:
^j
«•»
•••
o
VI
e
o
•*-
0
u
«••
L.
^J
jf*
CO
jr-^
GOTO
a. en
Q- E
o in
»-i <*
tj
•— u
(Q *^*
o «
V)
VI
J
•a
9
o-
«•—
r"»
C
«
JC
4^
*>
o
o
JC
u
•*•
»—
CSI
1
•f
•— o
-,
*"
t
••M
a
^J*
••—
•••
c
a.
e
Q.
f^
^k
VI
u
o
u
^^ '
1
•4-
•3
O
O
+
«p.
3
cr
**•
^™ •
rs
c
^M
m
^^
>»
JC
D
^B
U
111-33
-------
O O
o •—
»—» X
o
r-> t—
I
o
cn
V
o
e
«l 0
Permlsslbl
oncentrati
U
u
§
o
O.
*
le £
-------
i vl
j-c
oo
UJ
O
o
o>
OJ
c
41 O
43 -*J>
•r- «O
«/» i_
t/1 4->
•«- C
E 4>
U U
41 C
0. o
u
g
o
0.
^
*•* ^*
e [o
41 "»<
12
o
c «
••- i.
\_/ ^4
CO 4>
4)
0.
U 4»
°v» «o
>•! ^j
S^
*«
u
V
JC
^^
I
•4-
*
•^B
1
vt
«A
3
«A
»
Sj
O
•5
•o
u
4^
2
o
e
41
**
CM
JC
00
CO
.E
E
0
«— (
t
4Q
U
0
^.
^Z
o
ft)
^J
|Q
o
QQ
U
C
«^>
ISI
(\J
JC
CO
^^
&
CL
«— I
t
|Q
U
o
•*•
T3
^_
O
vt
41
•^
U
O
JC
o
c
««»•
INI
•^H
1
•*•
-L t
«— o
U E
o «
*~ VI
w>
^
•a
|H
o
4>
•o
C
2,
u
tj
c
^
^J
1
4-
t
•a
u
0
' +
-o
JIT
0
«A
4t
+J>
<*_
^M»
3
IA
O
"gj
z
U
C
fsj
CJ
1
4-
t
IQ
U
0
^
•o
jm
o
V)
41
•O
c
o
^«»
3
^«
Q
c
«
JC
CL.
U
C
«^»
1^4
CU
I
3 t
^- o
«e •*-
u E
o
^
^
•o
)H
0
w»
41
•o
g*
CL
^|
O
a.
u
c
4pV
^
111-35
'•AS <»\2 208149
------- |