T55.3 .H3
S72
1988i
540R88101
Standard Operating
Safety Guides
Waste
U-s- EPA, REGION V
U.S. Environmental Protection Agency
Region 5, Library (PH2J)
77 West Jackson Boulevard, 12th Floor
Chicago, II 60604-3590
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t
V
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON. D.C. 20460
JUL
MEMORANDUM
SUBJECT: Standard Operating Safety Guides, j0\ilyj 18 B8
/ l
Henry L. Longest II, Director v^>- r
Office of Emergency and Remedial Response
FROM:
TO:
Regional Office Addressees
The enclosed Standard Operating Safety Guides, July 1988, replace
the November 1984 edition. The guides have been updated and
revised to reflect the experience EPA personnel have gained in
responding to environmental incidents involving hazardous
materials.
The Standard Operating Safety Guides are in accordance and
consistent with the policies and procedures for employee health
and safety contained in EPA's Health and Safety Manual, May 5,
1984. The current OSHA regulations (29 CFR 1910, Part 120) for
hazardous waste workers has also been incorporated into these
guides.
The guides are not meant to be a comprehensive safety manual for
incident response. Rather, they provide information on health and
safety to complement professional judgement and experience, and
to supplement existing Regional Office safety procedures.
If you have any questions or comments concerning the guides,
please contact Mr. Timothy Fields, Jr., Director, Emergency
Response Division or Dr. Joseph Lafornara, Chief, Environmental
Response Branch.
Addressees
Director,
Director,
Director,
Director,
Director,
Director,
Director,
Environmental Services Division, Regions I, VI, and VII
Office of Emergency and Remedial Response, Region II
Hazardous Waste Management Division, Regions III and V
Air and Waste Management Division, Region IV
Waste Management Division, Region VIII
Toxic and Waste Management Division, Region IX
Hazardous Waste Division, Region X
cc Gene Lucero, Director, OWPE
Sylvia Lowrance , Director, OSW
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STANDARD OPERATING SAFETY GUIDES
JULY 1988
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF EMERGENCY AND REMEDIAL RESPONSE
EMERGENCY RESPONSE DIVISION
ENVIRONMENTAL RESPONSE BRANCH
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TABLE OF CONTENTS
Environmental Incidents, Part 1 Page 1-1
Standard Operating Safety Procedures, Part 2 Page 2-1
Health and Safety Requirement, Part 3 Page 3-1
Site Safety Plan, Part 4 Page 4-1
Annex 1 - Summary of the Occupational Safety and Page Al-1
Health Administration's Requirements
Annex 2 - ERT's Safety Checklist Page A2-1
Annex 3 - Site Health and Safety Plan, Page A3-1
Table of Contents
Initial Site Survey and Reconnaissance, Part 5 Page 5-1
Levels of Protection, Part 6 Page 6-1
Stress, Part 7 Page 7-1
Site Control - Work Zones, Part 8 Page 8-1
Site Control - Decontamination, Part 9 Page 9-1
Annex 4 - Level A Decontamination Page A4-1
Annex 5 - Level B Decontamination Page A5-1
Annex 6 - Level C Decontamination Page A6-1
Annex 7 - Level A Decontamination, Minimum Layout Page A7-1
Air Surveillance, Part 10 Page 10-1
Annex 8 - Guide to Environmental Response Team's Page A7-1
Air Surveillance Program
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
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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 the public's health and welfare or the
environment. The incident may be an emergency, requiring a
prompt response, or a longer-term remedial action at an
abandoned hazardous waste site. Regardless of how it happens,
each incident presents special problems. Response personnel
must evaluate these problems and determine an effective course
of action to abate the situation.
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 public or the environment as well as
response personnel. Physical hazards may also be encountered.
Workers may fall, trip, be struck by objects, or be subjected
to danger from electricity and heavy equipment. Injury and
illness may also occur due to the physical stress of response
personnel. While the response activities needed at each
individual incident are unique, there are many similarities.
One is that all responses require protecting the health and
ensuring the safety of response personnel.
II. EXPOSURE TO TOXIC SUBSTANCES
Toxic (including radioactive material and biological agents)
or chemically active substances present a special concern
because they can be inhaled, ingested, or be absorbed through
or destructive to the skin. They may exist in the air, or due
to site activities, become airborne. Liquids or sludges can
splash on the skin. The effects of these substances can vary
significantly. Ingested or inhaled the substances may cause
no apparent illness or they can be fatal. On the skin they
may cause no demonstrable effects. Other substances, however,
may damage the skin or be absorbed through it, leading to
systemic toxic effects.
Two types of potential exposures exist:
Acute; Exposures occur for relatively short periods
of time, generally minutes to 1-2 days. Concentrations
of toxic air contaminants are high relative to their
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protection criteria. In addition to inhalation, airborne
substances might directly contact the skin, or liquids
and sludges may be splashed on the skin or into the eyes,
leading to toxic effects.
Chronic; Continuous exposure occurs over longer periods
of time, generally months to years. Concentrations of
inhaled toxic contaminants are relatively low. Direct
skin contact by immersion, splash, or by contaminated air
involves contact with substances exhibiting low dermal
activity.
In general, acute exposures to chemicals in air are more
typical in transportation accidents and fires, or releases at
chemical manufacturing or storage facilities. High
concentrations of contaminants in air usually do not persist
for long periods of time. Acute skin exposures may occur when
workers must be in close contact with the substances in order
to control the release, for example, patching a tank car, off-
loading a corrosive material, uprighting a drum, or to contain
and treat the spilled material.
Chronic exposures are usually associated with longer-term
removal and remedial operations. Contaminated soil and debris
from emergency operations may be involved, soil and ground
water may be polluted, or temporary impoundment systems may
contain diluted chemicals. Abandoned waste sites typically
represent chronic exposure problems. As activities start at
these sites personnel engaged in certain activities (sampling,
handling containers, or bulking compatible liquids) face an
increased risk of acute exposures from splashes, or from
vapors, gases, or particulates that might be generated.
At any specific incident, the hazardous properties of the
materials may only represent a potential risk. For example,
if a tank car of liquified natural gas is involved in an
accident remains intact, the risk from fire and explosion is
low. In other incidents, the risks to response personnel are
high. For instance, when toxic or flammable vapors are being
released from a ruptured tank truck. The continued health and
safety of response personnel requires that the risks (real or
potential) at an episode be assessed and appropriate measures
instituted to reduce or eliminate the threat to response
personnel.
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III. HEALTH AND SAFETY OF RESPONSE PERSONNEL
To reduce the risks to personnel responding to hazardous
substance incidents, an effective health and safety program
must be developed and followed. As a minimum, a comprehensive
worker health and safety program should address:
Safe work practices.
Engineered safeguards.
Medical surveillance.
Environmental and personnel monitoring.
Personnel protective equipment.
Education and training.
Standard operating safety procedures.
As part of a comprehensive program, standard operating safety
procedures 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. At a particular incident they are adapted and
modified to correspond to the safety requirements that are
needed. For example, the requirement for personnel to wear
protective equipment is an initial consideration for all
incidents. The 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 for protecting the health and safety of response
personnel. The guidance included is not meant to be a
comprehensive treatment of the subjects covered. Rather, it
is meant to be used as an addition to, and to complement
professional training, experience, and knowledge.
IV. U.S. EPA OCCUPATIONAL HEALTH AND SAFETY POLICIES
The U.S Environmental Protection Agency's (EPA) Occupational
Health and Safety Staff is responsible for developing,
supporting, and evaluating a program to protect the health
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and safety of EPA employees. The Standard Operating Safety
Guides complement and supplement the policies, procedures,
and practices contained in EPA's Occupational Health and
Safety Manual (EPA Order 1440), particularly, Chapter 9,
Hazardous Substances Responses, EPA Order 1440.2, Health and
Safety Requirements for Personnel Engaged in Field Activities,
and EPA Order 1440.3 , Respiratory Protection.
VI. U.S. OSHA HEALTH AND SAFETY REGULATIONS
The U.S. Occupational Safety and Health Administration (OSHA)
has regulations governing employee health and safety at
hazardous waste operations and during emergency responses to
hazardous substance releases. These regulations (29 CFR
1910.120) contain general requirements for safety and health
programs, site characterization and analysis, site control,
training, medical surveillance, engineering controls, work
practices along with personal protective equipment, exposure
monitoring, informational programs, material handling,
decontamination, emergency procedures, illumination,
sanitation, and site excavation.
EPA's Standard Operating Safety Guides supplement and
complement these regulations, but for specific legal
requirements, OSHA's regulations must be used. Other OSHA
regulations may pertain to employees working with hazardous
materials or working at hazardous waste sites. These, as well
as, state and local regulations must also be considered when
developing worker health and safety programs.
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PART 2
STANDARD OPERATING SAFETY PROCEDURES
I. INTRODUCTION
There are many procedures for performing the variety of
tasks associated with a response to environmental incidents
involving hazardous substances. These may be administrative,
technical, or management-oriented. All of these procedures
are intended to provide uniform instructions for accomplish-
ing a specific task. In addition to other types of procedu-
res, safety-oriented operating procedures are needed. The
purpose of this document is to provide selected standard
operating safety guides which can be used by other organiza-
tions to develop more specific operating safety procedures.
II. DEVELOPMENT OF STANDARD OPERATING SAFETY PROCEDURES
A major consideration in responding to accidental releases
of hazardous substances or to abandoned hazardous waste
sites, is the health and safety of response personnel. Not
only must a variety of technical tasks be conducted effi-
ciently, but they must be accomplished safely. Appropriate-
ly equipped and trained personnel, combined with standard
operating procedures, help reduce the possibility of harm to
response personnel.
Standard operating safety procedures should be developed and
written by competent safety professionals. To be effective:
They must be prepared in advance. Developing and
writing safe, practical procedures is difficult to
accomplish when done 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.
They must be understandable, feasible, and appropriate.
All personnel involved in site activities must have
access to copies of the safety procedures and be
briefed on their use.
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Response personnel must be trained and periodically re-
trained in personnel protection and safety.
III. ADAPTATION TO SITE SPECIFIC RESPONSE ACTIVITIES
In concept and principle, standard operating safety
procedures 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
initially be needed 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. Containment, cleanup, and disposal
activities may be required.
All of these activities require that safety procedures be
developed or existing procedures be adapted so that response
personnel are protected.
IV. STANDARD OPERATING SAFETY GUIDES
The standard operating safety guides contained in this
document consist of technical information that should be
considered in developing standard operating safety
procedures. For a given incident, the guides recommended
herein should be adapted and modified to provide the safety
criteria required to protect response personnel against the
hazards created by that specific incident.
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PART 3
HEALTH AND SAFETY REQUIREMENTS
I. INTRODUCTION
Personnel responding to environmental incidents involving
hazardous substances may encounter a wide range of health
and safety problems. Besides hazards associated with the
physical, chemical, and toxicological properties of the
materials involved, other safety concerns, such as
electrical hazards, heat stress, cold exposure, faulty
equipment, and construction dangers, can also have adverse
effects on personnel.
To ensure the safety of response personnel, an effective,
comprehensive health and safety program must be established
and followed. This part discusses the minimum components
that should be addressed in a health and safety program.
II. MEDICAL PROGRAM
To safeguard the health of response personnel, a medical
program must be developed, established, and maintained.
This program has two essential components: routine health
care and emergency treatment.
A. Routine Health Care
At a minimum, routine health care and maintenance should
consist of:
Pre-employment medical examinations to establish the
individual's state of health, baseline physiological
data, and ability to wear personnel protective
equipment.
Annual examinations, of which, the frequency and
content will be determined by the examining physician.
The examination may vary depending on: the length and
type of work assignment, the frequency of exposure, and
the individual's physical condition.
More frequent examinations (determined by the
physician) due to the workers"s assignment and
potential exposure levels.
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Special medical examinations, care, and counseling in
case of known or suspected exposures to toxic substances.
Any special tests needed depend on the chemical substance
to which the individual has been exposed.
Termination examinations conducted at the end of
employment or upon reassignment. The content of the
examination should be similar to the baseline
examination.
B. Emergency Medical Care and Treatment
The Medical Program must address emergency medical care
and treatment of response personnel, including possible
exposures to toxic substances and injuries resulting from
accidents or physical hazards. The following items
should be included in emergency care provisions:
Name, address, and telephone number of the nearest
medical treatment facility. This should be
conspicuously posted. A map and directions for
locating the facility, plus the travel time, should
be readily available.
The facility's ability to provide care and treatment
of personnel exposed or suspected of being exposed
to toxic (or otherwise hazardous) substances. If the
facility lacks toxicological capability,
arrangements should be made for consultant services.
Administration 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 advanced first aid and emergency
lifesaving training.
Provisions for the rapid identification of the
substance to which the worker has been exposed (if
this has not previously been done). This
information must be given to medical personnel.
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Procedures for decontamination of injured workers
and preventing contamination of medical personnel,
equipment, and facilities.
Protocols for heat stress and cold exposure
monitoring, and working in adverse weather
conditions.
Medical evacuation requirements.
The EPA's Environmental Response Team's "Occupational
Medical Monitoring Program Guidelines for SARA Field
Activity Personnel", June 2, 1988, addresses specific
medical monitoring concerns and procedures.
C. Maintenance of Records
Due to the nature and risk of the work associated with
hazardous material incidents and that the potential
exposure to harmful substances may have an adverse
effects on an employee, it is essential that proper
records be maintained and retained.
Medical records should contain the following information:
Any occupational exposure.
Employees use of respirators and personnel
protective clothing.
Any work-related injuries.
Physician's written opinion of medical problems and
treatment.
Record of all medical examinations.
D. Indicators of Toxic Exposure
As part of the medical program, response personnel should
be instructed in the signs and symptoms that might
indicate potential exposure to toxic substances.
Some of these are:
Observable by others
changes in complexion, skin discoloration
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lack of coordination
changes in demeanor
excessive salivation
pupillary response
changes in speech pattern
breathing difficulties
difficulties with coordination
coughing
Non-Observable by others
headaches
dizziness
blurred vision
cramps
irritation of eyes, skin, or respiratory
tract
behavior changes
III. HEALTH AND SAFETY TRAINING
Safety and health training must be an integral part of the
total response health and safety program. Safety training must
be continuous and frequent for response personnel to maintain
their proficiency in the use of equipment and their knowledge
of safety requirements.
All personnel involved in responding to environmental
incidents and who could be exposed to hazardous substances,
health hazards, or safety hazards must receive safety training
prior to carrying out their response functions. Health and
safety training must, as a minimum, include:
Use of personal protective equipment, for example,
respiratory protective apparatus and protective clothing.
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Use of personal protective equipment, for example,
respiratory protective apparatus and protective
clothing.
Safe work practices, engineering controls, and standard
operating safety procedures.
Hazard recognition and evaluation.
Medical surveillance requirements, symptoms and signs
which might indicate medical problems, and first aid.
Site safety plans and plan development.
Site control and decontamination.
Use of monitoring equipment, if applicable.
Training must be as practicle as possible and include hands-
on use of equipment and exercises designed to demonstrate
and practice classroom instruction. Formal training should
be followed by at least three days of on-the-job experience
working under the guidance of an experienced, trained
supervisor. All employees should, as a minimum, complete
annually an 8 hour safety refresher training course. Health
and safety training must comply with OSHA's training
requirements as defined in 29 CFR 1910.120.
IV. QUALIFIED SAFETY PERSONNEL
Personnel responding to chemical incidents must make many
complex decisions regarding safety. Making these decisions
correctly requires more 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 professional
judgment.
Only a competent, qualified person (safety specialist) has
the technical judgment to evaluate a particular incident and
determine the appropriate safety requirements. It's through
a combination of professional education, on-the-job
experience, specialized training, and continual study, that
the safety professional acquires the expertise to make sound
decisions.
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V. STANDARD OPERATING SAFETY PRACTICES
Standard operating safety procedures should include safety
precautions and operating practices, that all responding
personnel should follow. These would include:
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 beverages should be avoided,
in the off-duty hours, during response operations.
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B. 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 protection and chemical
protective 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 protection. As a minimum, two
other persons, suitably equipped, are required as
safety backup 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 unfamiliar operations
prior to doing the actual procedure.
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.
Wind indicators visible to all personnel should be
strategically located throughout the site.
Personnel and equipment in the contaminated area
should be minimized, consistent with effective
site operations.
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Work areas for various operational activities must
be established.
Procedures for leaving a contaminated area must be
planned and implemented prior to going on-site.
Work areas and decontamination procedures must be
established based on expected site conditions.
VI. SITE SAFETY PLAN
A site safety plan must be developed and implemented for all
phases of site operations. The safety plan should address
the safety and health hazards of each phase of the site
operation, as well as specify the requirements and
procedures for employee protection.
The plan must be written and posted on site,.
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 adhere to the information contained
in the Site Safety Plan.
A more detailed description of site safety plans and what
they must contain is in Part 4.
VII. SUMMARY
The health and safety of response personnel are major
considerations in all response operations. All site
operation planning must incorporate an analysis of the
hazards involved and procedures for preventing or minimizing
the risk to personnel.
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PART 4
SITE SAFETY PLAN
I. INTRODUCTION
The purpose of the site safety plan is to establish policies
and procedures for protecting the health and safety of
response personnel during all operations conducted at an
incident. It contains information about the known or
suspected hazards, routine and special safety procedures that
must be followed, and other instructions for safeguarding the
health of the responders.
A site safety plan shall be prepared and reviewed by qualified
personnel for each hazardous substance response. Before
operations at an incident commence, all safety aspects of site
operations should be thoroughly examined. A safety plan is
then written based on the anticipated hazards and expected
work conditions. The plan should be 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 responses generally require the use of a
generic safety plan, standing standard operating procedures,
and special verbal instructions until (if 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. CATEGORIES OF HAZARDOUS MATERIALS RESPONSES
Three general categories of response exist: emergencies,
hazardous waste site investigations 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 considerably. These
variations are generally due to the reason for responding (or
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category of response), information available, and the severity
of the incident with its concomitant dangers to the responder.
A. Emergencies
1. Situation:
Emergencies generally require prompt action to
prevent or reduce undesirable effects. 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, hazards, numbers of responders involved,
type of work required, population affected, and
other factors. Emergencies usually last from a few
hours to a few days.
Information available: Varies from none to
much. Usually, information about the
materials involved and their associated
hazards, is quickly obtained in transportation
related incidents, or incidents involving fixed
facilities. Determining the substances
involved in other incidents, such as mysterious
spills or illegal dumping requires considerable
time and effort.
Time available: Little time. Generally requires
prompt action to bring the incident under
control.
Reason for response: To implement prompt and
immediate 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. Therefore,
general safety plans for emergency response (generic
plans) are developed prior to responding and are
implemented when an emergency occurs.
Responding organizations must rely on their existing
generic safety plan and written standard operating
safety procedures adapted to meet incident-specific
conditions, and the use of verbal safety
instructions.
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Since there is a heavy reliance on verbal
communications, an effective system to keep all
responders informed must be established. Whenever
possible, these incident-specific instructions
should be written and posted.
B. Hazardous Waste Site Investigations
1. Situation:
In non-emergency responses, for example, preliminary
inspections at abandoned wastes sites or more
comprehensive waste site investigations, the
objective is to determine and characterize: 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 1-5 days.
Complete investigations may last over a longer
period of time (months).
Information available: Much background
information is often available, but may not be
specific enough for making initial safety
decision. On-site information more fully
developed through additional surveys and
investigations.
Time available: In most cases adequate time is
available to make a preliminary evaluation of
the site's characteristics and to develop a
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 determine, on a
preliminary basis, the hazards anticipated and other
conditions associated with the site and to write
initial safety plans. In scope and detail, these
plans tend to be brief and contain safety require-
ments for specific on-site work relevant to
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collecting data. As information is developed through
additional investigations, the safety plan is
modified and, if necessary, more detailed and
specific requirements added.
C. Remedial Actions
1. Situation:
Remedial actions are cleanups which may take many
years to complete. 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
the efforts of many people, a detailed logistics and
support base, extensive equipment, and more involved
work activities.
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.
Effects on Plan:
Since ample time is available before work commences,
site safety plans tend 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.
III. PRELIMINARY SITE EVALUATION AND SAFETY PLAN
A preliminary evaluation of a hazardous waste site's
characteristics must be performed, by a qualified person,
prior to anyone going on the site. The information obtained
is used to determine the appropriate health and safety control
procedures needed to protect initial entry team personnel from
identified or suspected hazards. After initial site entry, a
more detailed evaluation of site characteristics is made based
upon information collected by the entry team. The preliminary
site safety plan is then modified and refined.
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Of immediate concern are known or expected substances that
are Immediately Dangerous to Life and Health (IDLH) through
skin absorption or inhalation, or other conditions that may
cause death or serious injury. Some examples of these
conditions are: fire or explosive potential, visible vapor
clouds, radioactive labeled material, and confined space
entry.
A preliminary evaluation of the site's characteristics shall
include:
Incident location and name.
Site description, topography, and size.
Descriptions of the activities or tasks to be done.
Duration of planned of planned activities.
Site accessibility.
Hazardous substances and health hazards involved or
expected.
Chemical, physical, and toxicological properties of the
hazardous substances involved.
Behavior and dispersion of material involved.
Availability and capabilities of emergency assistance.
Additional information that might be useful is:
Types of containers, storage, or transportation methods.
Prevailing weather condition and forecast.
Surrounding populations and land use.
Ecologically sensitive areas.
Facility records.
Preliminary assessment reports.
Off-site survey results.
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The information initially available, collected during a
preliminary inspection, or obtained through subsequent
investigations provides a basis for developing a detailed,
site-specific safety plan. This type of information is then
used along with the reason for responding to develop a
comprehensive safety plan.
The safety plan is tailored to the conditions imposed by the
incident and to its environmental setting. As work progresses
and as additional information becomes available, the safety
plan is reviewed, modified, and kept current.
IV. GENERAL REQUIREMENTS FOR ROUTINE OPERATIONS
Routine operations are all those activities that may be
required in responding to an emergency or a remedial action
at a hazardous waste site in order to identify, evaluate, and
control (including cleanup) the incident. These activities
may involve a high degree of risk, but are standard operations
generally involved in responding to that type of incident.
Safety practices for routine operations closely parallel
accepted procedures used in industrial hygiene and industrial
safety. 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.
Key Personnel and Alternates
The plan must identify the incident manager as well as
the site safety and health officer (and alternates) and
any other personnel responsible for site safety. It
should also identify key personnel associated with other
site operations. The names, telephone numbers,
addresses, and organizations of these people must be
listed in the plan and posted in a conspicuous place.
Known Hazards and Risks
All known or suspected physical, biological, rad-
iological, or chemical hazards must be described. 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, potential impact on public assessed, and changes
made in the plan. These evaluations need to be repeated
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frequently since much of the plan is based on this
information.
Routine or Special Training Requirements
Personnel must be trained not only in general safety
procedures and use of safety equipment, but in any
specialized work they may be expected to do.
Levels of Protection
The Levels of Protection to be worn at locations on-site
or by work functions must be designated. This includes
the specific types of respirators and type of chemical
protective 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.
Site-Specific Medical Requirements
Specialized medical requirements should be determined
when unusual hazards are expected to be encountered.
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
identify chemicals present, their hazards, possible
routes of migration off-site, and associated safety
requirements.
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.
Site 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 is required.
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Decontamination
Decontamination procedures for personnel and equipment
must be established. Arrangements must also be made for
the proper disposal of contaminated material, solutions,
and equipment.
Emergency Response Plan
A plan for responding safely and effectively to emergency
situations that might develop at the site must be
developed and included as part of the overall site safety
plan.
Confined Space Entry
Procedures to assure the safety of personnel who may have
to make confined space entry must be established.
Weather-Related Problems
Weather conditions can affect site work. Temperature
extremes, high winds, precipitation, and storms, can
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 protective clothing, must be considered
and procedures established to monitor for and minimize
heat stress.
V. ON-SITE EMERGENCIES
The plan must address site emergencies-occurrences that
require immediate actions to prevent additional problems or
harm to responders, the public, property, or the environment.
In general, all 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 detailed information for
managing these contingencies.
To accomplish this, the contingency plan must:
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Establish Site Emergency Procedures
List the names and emergency functions of on-site
personnel responsible for emergency actions along
with the special training required.
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 and Rescue Agency
Police Department
Health Department
Explosive experts
Local hazardous material response units
Emergency Services offices
Radiation experts
Address and define procedures for the rapid
evacuation of workers. Clear, audible warning
signals should be established. Well-marked emergency
exits must be located throughout the site, as well
as internal and external communications plans devel-
oped.
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 available
off-site.
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Address emergency medical care.
Determine location of nearest medical or emergency
care facility and determine their capability to
handle chemical exposure cases.
Arrange for, in advance, treating, admitting, and
transporting of injured or exposed workers.
Post the location of medical or emergency care
facilities, required travel time, directions, and
telephone number.
Determine location of local physician's office,
along with travel directions, hours of availability,
and post telephone number if other medical care is
not available.
Determine nearest ambulance service and post
telephone number.
List the names of responding organization's
physicians, safety officers, or toxicologists and
telephone number. Also include nearest poison
control center, if applicable.
Maintain accurate records on any exposure or
potential exposure or injuries to site workers
during an emergency (or routine operations).
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 technicians 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.
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VI. 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 can
result from verbal orders. The plan must be reviewed and
approved by qualified personnel. Once the safety plan is
implemented, it needs periodic examination and modification,
if necessary, to reflect any changes in site work and
conditions.
When there is more than one organization involved at the
incident, the development of a safety plan should be a
coordinated effort among the various agencies. Once the plan
has been reviewed and approved by a qualified safety
professional, lead personnel from each organization should
sign the plan to document that they are in agreement with the
provisions as well as to verify that their organization will
follow it accordingly.
A safety and health officer must be appointed to ensure that
the requirements of the safety plan are implemented. The
safety officer has the authority to halt all operations if
conditions become unsafe. In addition, the safety officer is
responsible for instructing personnel on the provisions of
the safety plan. Frequent safety meetings should be held to
keep personnel informed about site hazards, changes in
operating plans, modifications of safety requirements, and
for any additional exchanges of information. All those on site
must comply with the provisions set forth in the safety plan.
Frequent audits by the incident manager or the safety officer
should be made to determine compliance with the plan's
requirements. Any deviations should be brought to the
attention of the incident manager and any deficiencies
corrected. Modifications in the plan should be reviewed and
approved by appropriate personnel.
VII. ANNEXES TO PART FOUR
Annex 1 is a summary of the U.S. Occupational Safety and
Health Administration's requirements (20 CFR 1910.120) for:
1) the preliminary characterization that must be performed,
by a qualified person, prior to the initial entry onto a
hazardous waste site, and 2) the minimum requirements for a
site safety and health plan.
The Incident Safety Check off List, Annex 2, is used by
members of the U.S. EPA's Environmental Response Team when
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responding to an incident. It is not a health and safety plan,
but an individuals record of incident related safety
procedures or requirements. Other organizations might want to
use a similar type of safety check off list to have a
historical record of an individual's safety experience.
Annex 3 is the Table of Content for the Environmental Response
Team's Field Operating Safety Procedures, Site Health and
Safety Plan. The Table of Contents is a good summary of the
information that must be in a site safety plan.
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ANNEX 1
SUMMARY OF THE U.S. OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION'S
REQUIREMENTS FOR
PRELIMINARY EVALUATION AND SITE SAFETY AND HEALTH PLANS
(Interim Final Rule, Aug. 10, 1988)
PRELIMINARY EVALUATION: Prior to entering a site, the following
information must be obtained. In addition, all suspected conditions
that are Immediately Dangerous to Life and Health (IDLH) shall be
identified.
Site location and size.
Description of response activities or job function.
Planned duration of employee activity.
Site topography.
Site accessibility by air and roads.
Pathways for hazardous substance dispersion.
Present status and capabilities of emergency response
teams for employee on-site emergencies.
Hazardous substances involved or expected at the site
and their chemical and physical properties.
SITE SAFETY AND HEALTH PLAN: Is part of the overall Safety and
Health Program and shall be available on-site for employee
inspection. It must include:
Name of key personnel and alternates, and health and
safety personnel.
Task/operation safety and health risk analysis.
Employee training.
Personal protective equipment to be used.
Frequency and types of air monitoring, personnel
monitoring, and sampling techniques.
Site control measures.
Decontamination procedures.
Site standard operating procedures.
Site contingency plan.
Confined space entry procedures.
Medical surveillance program.
NOTES: 1. Pre-entry safety briefings shall be held prior
to initiating any site activities.
2. Inspections shall be conducted by the Site
Safety and Health Supervisor.
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ANNEX 2
INCIDENT SAFETY CHECK OFF LIST
I. BEFORE FIELD ACTIVITY -
Employee
1. Incident: Site City State
Response Dates
2. Activity Description:Site Evaluation Containment Well Drilling Facility Inspection,
Sampling-Air Water Drum Soil Residential Other
3. Type of Response: Spill Fire Site Train Other,
4. Site Topography: Mountains Rivers Valley Rural _
Suburban Level Slopes Unknown.
5. Incident Safety Plan: Region Reviewed
ERT Briefed
Facility Not Developed
6. Site Accessibility: Road: Good Air: Good
Fair Fair
Poor Poor
7. Suspected chemical (s) and pathway with source (s) involved: (A)
(B) (C) (D)
8. Emergency Response Teams Present for First Aid, etc. Yes No.
9. Protective Level (s) Selected: (A) (B) (C) (D)_
(a) If Level "C" -1. Identify Canister
(b) If Level "D" - JUSTIFY:
10. SCBA Identify Buddy System: Office/Name
11. Last Response: (a) Level Used: (A) (B) (C) (D)
(b) Medical Attention/Exam Performed: Yes No
II. AFTER RESPONSE
1. Protective Level Used: (A) (B) (c) (D)
a. Level "C" - identify canister:
b. Level "D" - JUSTIFY:
c. Level B or C skin protection: Tyvek Tyvek/Saran Acid/Rain Other
2. List possible chemical exposure: Same as above: (A)
(B) (C) (D)
3. Equipment Decontamination: (a) clothing (b) respirator (c) monitoring
Disposed:
Cleaned:
No Action:
4. Approximate time in exlusion area: hours per day for days
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
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ANNEX 3
SITE HEALTH AND SAFETY PLAN
TABLE OF CONTENTS
1.0 INTRODUCTION 1
1.1 Scope and Applicability of the Site Health and Safety Plan 1
1.2 Visitors 1
2.0 KEY PERSONNEL/IDENTIFICATION OF KEY HEALTH AND SAFETY PERSONNEL 2
2.1 Key Personnel 2
2.2 Site Specific Health and Safety Personnel 3
2.3 Organization Responsibilities 4
3.0 TASK/OPERATION SAFETY AND HEALTH RISK ANALYSIS 5
3.1 Historical Overview of Site 5
3.2 Task by Task Risk Analysis 5
4.0 PERSONNEL TRAINING REQUIREMENTS 8
4.1 Preassignment Training 8
4.2 Site Supervisors Training 8
4.3 Site Specific Training/Briefing Topics 8
4.4 Morning Meeting Topics 9
5.0 PERSONAL PROTECTIVE EQUIPMENT TO BE USED 10
5.1 Levels of Protection 10
5.2 Level A Protection Equipment 11
5.3 Level B Protection Equipment 11
5.4 Level C Protection Equipment 12
5.5 Level D Protection Equipment 12
5.6 Reassessment of Protection Program 13
5.7 Specific Levels of Protection Planned for [SITE NAME] 13
5.8 Standard Operating Procedures for Respiratory Protection 13
Devices
6.0 MEDICAL SURVEILLANCE REQUIREMENTS 20
6.1 Baseline Monitoring 20
6.2 Periodic Monitoring 20
6.3 Site Specific Monitoring 20
6.4 Exposure/Injury Medical Support 21
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SITE HEALTH AND SAFETY PLAN
TABLE OF CONTENTS (CONT'D)
7.0 FREQUENCY AND TYPES OF AIR MONITORING 22
7.1 Monitoring Instruments 22
7.2 Personal Sampling 26
7.3 Specific Contaminants to be Monitored for at [SITE NAME] 28
8.0 SITE CONTROL MEASURES . 32
8.1 Buddy System • 32
8.2 Site Communications Plan 32.
8.3 -Work Zone Definition 32
8.4 Nearest Medical Assistance 35
8.5 Safe Work Practices 35
9.0 DECONTAMINATION PLAN 39
9.1 Levels of Decontamination Protection Required 39
for Personnel
9.2 Equipment Decontamination 39
9.3 Disposition of Decontamination Wastes 39
10.0 EMERGENCY RESPONSE/CONTINGENCY PLAN 43
10.1 Pre-Emergency Planning 43
10.2 Lines of Authority 43
10.3 Emergency Recognition/Prevention 43
10.4 Evacuation Routes/Procedures 43
10.5 Emergency Equipment/Facilities 45
10.6 Emergency Contact/Notification System 45
10.7 Emergency Facilities 46
10.8 Evacuation Routes 46
10.9 Medical Emergencies 46
10.10 Fire or Explosion 46
10.11 Spill or Leaks 47
11.0 CONFINED SPACE ENTRY PROCEDURES 48
11.1 Definitions 48
11.2 General Provisions 48
11.3 Procedures for Confined Space Entry 50
11.4 Confined Space Observer 51
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PART 5
INITIAL SITE SURVEY AND RECONNAISSANCE
I. INTRODUCTION
The team initially entering the site is to accomplish one or
more of the following objectives:
Determine the hazards that may exist affecting public
response personnel, the public, and the environment.
Verify existing information or obtain new information
about the incident.
Evaluate the need for prompt action to mitigate the
incident.
Collect additional information to determine the safety
requirements for personnel 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 or degree of hazards, and risks which may
exist. Based upon available information (shipping manifests,
transportation placards, existing records, container labels,
witnesses, etc.) or from 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 objective of an on-site survey is to determine,
on a preliminary basis, hazardous or potentially hazardous
conditions. The main effort is to rapidly identify immediate
hazards that may affect response personnel, the public, or the
environment. Of major concern are the real or potential
dangers from fire, explosion, airborne contaminants,
radiation, and to a lesser degree, 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 measurements for organics should be made
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with one or more appropriate, properly calibrated survey
instruments.
When the presence or types of organic vapors/gases are
unknown, instruments such as a photoionization detectors
(PID) and flame ionization detectors (FID) operated in
the total readout mode or as a chromatograph, should be
used to detect organic vapors.
Until specific constituents can be identified, the
readout indicates total airborne substances to which the
instrument is responding. Identification of the
individual vapor/gas constituents may permit the
instruments to be calibrated to these substances and used
for more specific and accurate analysis.
Sufficient data should be obtained during the initial
entry to 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) map
selected candidate areas for more thorough qualitative
and quantitative studies.
Very high readings on PIDs or FIDs may also indicate the
possible displacement 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 non-specific inorganic
vapors and gases is extremely limited. Presently, PIDs
have very limited detection capability while PIDs have
none. (See Appendix I for characteristics). If specific
inorganics are known or suspected of being present,
measurements should be made with appropriate instruments,
if available. Colorimetric tubes are only practical if
the substances present are known or can be narrowed to
a few.
C. Radiation
A radiation survey should be done as part of the initial
characterization at abandoned hazardous waste site and
at hazardous material accidents whenever there is any
possibility that radioactive materials could be involved.
If no radiation is detected during the initial survey,
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subsequent surveys should be made at waste sites to make
certain that the initial monitoring results were correct.
Normal background exposure-rate for gamma radiation is
approximately 0.01 to 0.02 milliroentgen per hour (mR/hr)
or 10 to 20 microroentgen per hour (yJR/hr) on sensitive
gamma survey instruments. 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
1 mR/hr or above without the advice of a health
physicist. EPA's Office of Air 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 gamma, alpha, or beta radiation may be
present, but for a number of reasons may not cause a
response on the instrument. 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-supplying respirators are
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 additional organic vapor and combustible gas
measurements, since the air has been displaced by other
substances. Oxygen-enriched atmospheres increase the
potential for fires by their ability to contribute to
combustion or to chemically react with flammable
compounds and promote auto ignition.
E. 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
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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
observations which would help in evaluating site hazards.
Biological indicators such as dead fish or other animals
or stressed vegetation may indicate the presence of
hazardous materials. Land features; wind direction;
labels on containers indicating explosive, flammable,
toxic, or corrosive materials; conditions conducive to
splash or contact with unconfined liquids, sludges, or
solids; and other general conditions may also provide
some clues as to what hazards are present.
G. Direct-Reading Instruments
A variety of toxic air pollutants, (including organic
and inorganic vapors, gases, or particulates) can be
generated at an abandoned waste sites. Fires at chemical
manufacturing, storage, reprocessing, or formulating
facilities; fires involving pesticides, and many other
incidents also can generate air contaminants. Direct-
reading field instruments may be able to detect and
quantify some air contaminants, but they cannot detect
or measure all substances. Thus, negative readings on
instruments should not be interpreted as the complete
absence of airborne toxic substances. Verification of
negative results can only be done by collecting air
samples and having them analyzed in a laboratory using
more sophisticated analytical techniques.
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 may consist of
more than one entry.
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B. Priority for Initial Entry Monitoring
The primary concern of initial entry personnel are
atmospheric conditions which could affect their immediate
safety. These conditions are airborne toxic substances,
ignitable gases or vapors, oxygen depleted atmospheres,
and ionizing radiation. 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 or 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 or 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 6). Toxic
gases or vapors and radiation, unless known to be absent,
should be measured next.
For open, well-ventilated areas, combustible gases and
oxygen deficiency 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, there may be toxic
vapors or gases present and lack of sufficient oxygen to
sustain life. Entry teams should approach and monitor
these areas, whenever possible, from an upwind direction.
C. Periodic Monitoring
The monitoring surveys made during the initial site entry
phase are 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 the ambient atmosphere must
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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 instruments, 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 as 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 ignitable gases or vapors have been determined to
be absent.
F. Ambient Atmospheric Concentrations
Any indication of atmospheric hazards - toxic substances,
ignitable gases, lack of oxygen, and radiation - should
be viewed as a sign to proceed with care and
deliberation. Readings indicating non-explosive
atmospheres, low concentrations of toxic substances, or
other conditions may change rapidly, concomitantly
changing the associated risks. Extreme caution should
be exercised in continuing surveys when any atmospheric
hazards are indicated.
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TABLE 5-1
ATMOSPHERIC HAZARD ACTION GUIDES
MONITORING EQUIPMENT HAZARD
LEVEL
ACTION
Combustible Gas
Indicator
Explosive
< 10% LEL
Continue monitoring
with caution.
10-25% LEL Continue monitoring, but with
extreme caution, especially as
higher levels are encountered.
Oxygen Concentration
Radiation Survey
Instrument
Gamma
Radiation
> 25% LEL Explosion hazard! Withdraw
from area immediately.
< 19.5% Monitor wearing SCBA. NOTE:
Combustible gas readings not
valid in atmospheres < 19.5%
oxygen.
19.5-25% Continue monitoring with
caution. SCBA not needed based
only on oxygen content.
> 25% Discontinue monitoring.
Fire potential! Consult
specialist.
< 1 mR/hr Continue monitoring.
Consult a Health Physicist.
> 1 mR/hr Continue monitoring only upon
the advice of a Health
Physicist.
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TABLE 5-1 (Continued)
ATMOSPHERIC HAZARD ACTION GUIDES
MONITORING EQUIPMENT HAZARD
LEVEL
ACTION
Colorimetric Tubes
Photo ionization
Detector
Flame Ionization
Detector
Organic &
inorganic
vapors/gases
Organic
vapors/gases
Organic
vapors/gases
Depends on Consult reference
chemical manuals for air
concentration vs.
toxicity data.
Depends on Consult reference
chemical manuals for air
concentration vs.
toxicity data.
Depends on Consult reference
chemical manuals for air
concentration vs.
toxicity data.
NOTE: The correct interpretation of any instrument readout is difficult.
If the instrument operator is uncertain of the significance of a
reading, especially if conditions could be unsafe, a technical
specialist should immediately be consulted. Consideration should be
given to withdrawing personnel from the area until approval, by the
safety officer, is given to continue operations.
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PART 6
LEVELS OF PROTECTION
I. INTRODUCTION
Response personnel must wear protective equipment when there
is a probability of contact with hazardous substances that
could affect their health. This includes vapors, gases, or
particulates that may be generated by site activities, and
direct contact with skin-affecting substances. Full facepiece
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 helps
prevent ingestion of material.
Equipment to protect the body against contact with known or
anticipated 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 degree of
skin protection is needed.
Level C: Should be worn when a lesser level of
respiratory protection is needed than Level B. Skin
protection criteria are similar to Level B.
Level D; 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 the hazard
and risk of exposure.
Hazard: Type and measured concentration of the chemical
substance in the ambient atmosphere and its
toxicity.
Risk: Potential for exposure to substances in air,
splashes of liquids, or other direct contact
with material due to work being done.
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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
characterized.
Personnel protective equipment reduces the potential for
contact with toxic substances. Additionally, safe work
practices, decontamination, site entry protocols, and other
safety procedures further ensure the health and safety of
responders. Together, these provide an integrated approach
for reducing harm to response personnel.
III. LEVELS OF PROTECTION
A. Level A Protection
1. Personnel protective equipment
Pressure-demand, supplied-air respirator approved
by the Mine Safety and Health Administration (MSHA)
and National Institute for Occupational Safety and
Health (NIOSH). Respirators may be:
pressure-demand, self-contained breathing
apparatus (SCBA), or
pressure-demand, airline respirator (with an
escape bottle for atmospheres with, or having
the potential for, Immediately Dangerous to
Life and Health (IDLH) contaminant
concentrations).
Fully encapsulating chemical-resistant suit
Coveralls*, or
Long cotton underwear*
Gloves (inner), chemical-resistant
Boots, chemical-resistant, steel toe and shank.
(Depending on suit construction, worn over or under
suit boot)
Hard hat* (under suit)*
Disposable gloves and boot covers* (Worn over fully
encapsulating suit)
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Cooling unit*
2-Way radio communications (inherently safe)
(*) optional
2. Criteria for selection
Meeting any of these criteria warrants use of Level
A Protection:
The chemical substance has been identified and
requires the highest level of protection for
skin, eyes, and the respiratory system.
Substances with a high degree of hazard to the
skin are suspected to be present, and skin
contact is possible. Skin contact includes:
splash, immersion, or contamination from
atmospheric vapors, gases, or particulates.
Operations must be conducted in confined,
poorly ventilated areas until the absence of
substances requiring Level A protection is
determined.
Direct readings on field Flame lonization
Detectors (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, Level A is generally
worn when high concentrations of airborne sub-
stances that could severely effect the skin are
known or presumed to be present. Since Level
A requires the use of a self-contained
breathing apparatus more protection is afforded
to the eyes and respiratory system.
Until air surveillance data are available to
assist in the selection of the appropriate
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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 substances
having severe skin affecting properties.
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. An entry into an enclosed
space does not automatically warrant Level
A protection, but should serve as a cue
to carefully consider the justification
for a lower Level of Protection.
Suspected or known highly toxic
substances: Various substances that are
highly toxic, especially through skin
absorption, require Level A. Technical
grade pesticides, concentrated phenolic
compounds, Poison "A" compounds, fuming
corrosives, and a wide variety of organic
solvents are of this type. Carcinogens,
and infectious substances known or
suspected to be involved may require Level
A protection. Field instruments may not
be available to detect or quantify air
concentrations of these materials. Until
these substances are identified and their
concentrations determined, maximum
protection is necessary.
Visible indicators: Visible air emissions
from leaking containers or railroad or
truck 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 functions: Initial site entries are
generally walk-throughs in which
instruments and visual observations are
used to make a preliminary evaluation of
the hazards.
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In initial site entries, Level A should
be worn when:
there is a probability for exposure
to high concentrations 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 and subsequent environmental
monitoring, but also on the protective
properties of suit material as well. The
probability of contamination and ease of
decontamination must also be considered.
Examples of situations where Level A has been
worn are:
Excavating soil to sample buried drums
suspected of containing high
concentrations of dioxin.
Entering a cloud of chlorine to repair a
valve broken in a railroad accident.
Handling and moving drums known to contain
oleum.
Responding to accidents involving cyanide,
arsenic, and undiluted pesticides.
b. The fully encapsulating suit provides the
highest degree of protection to skin, eyes,
and respiratory system given that the suit
material resists chemicals during the time the
suit is worn. While Level A provides maximum
protection, all suit materials may be rapidly
permeated and degraded by certain chemicals.
These limitations should be recognized when
specifying the type of fully encapsulating
suit. Whenever possible, the suit material
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should be matched with the substance it is used
to protect against.
B. Level B Protection
1. Personnel protective equipment
Pressure-demand, supplied-air respirator
(MSHA/NIOSH approved). Respirators may be:
pressure-demand, self-contained breathing
apparatus, or
pressure-demand, airline respirator (with
escape bottle' for IDLH or potemtial for
IDLH atmosphere)
Chemical-resistant clothing (includes: overalls
and long-sleeved jacket or hooded, one or two-
piece chemical-splash suit or disposable
chemical-resistant, one-piece suits)
Long cotton underwear*, or
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 (inherently safe)
(*) optional
2. Criteria for selection
Meeting any one of these criteria warrants use of
Level B protection:
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The type and atmospheric concentration of toxic
substances has been identified and requires a
high level of respiratory protection, but less
skin protection than Level A. These would be:
Atmospheres with IDLH concentrations, but
the substance or its concentration in air
does not represent a severe skin hazard,
or
Chemicals or concentrations involved 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.
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 concentrations
of skin toxicants. (See Appendixes I and II.)
3. Guidance on selection
Level B does not afford the maximum skin (and
eye) protection 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 of liquids and lower concentrations
of chemicals in the ambient air.
At most abandoned, outdoor hazardous waste
sites, ambient atmospheric gas or vapor levels
usually do approach concentrations sufficiently
high to warrant Level A protection. In all but
a few circumstances, Level B should provide the
protection needed for initial reconnaissance.
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Subsequent operations require a re-evaluation
of Level B protection based on the probability
of being splashed by chemicals, their effect
on the skin, or the presence of hard-to-detect
air contaminants. The generation of highly
toxic gases, vapors, or particulates, due to
the work being done must also be considered.
b. The chemical-resistant clothing required in
Level B is available in a wide variety of
styles, materials, construction detail, and
permeability. One or two-piece garments are
available with or without hoods. Disposable
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
possibility for splash and vapor or gas
penetration, but is not a gas tight barrier.
These factors and other selection criteria all
affect the degree of protection afforded.
Therefore, a specialist should select the most
effective chemical-resistant clothing 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, selecting chemical-
resistant clothing (Level B) rather than a
fully encapsulating suit (Level A) is based on
the need for 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 destructive to or readily
absorbed through the skin by liquid
splashes, unexpected high levels of gases,
vapor, or particulates, or by other means
of direct contact.
Assessing the effect of the substance (at
its measured air concentrations or
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potential for splashing) on the small
areas left unprotected by chemical-
resistant clothing. A hooded garment,
taped to the mask with boots and gloves
taped to the suit, further reduces the
area for potential skin exposure.
c. For initial site entry and reconnaissance at
an open site, approaching whenever possible
from upwind, Level B protection (with good
quality, hooded, chemical-resistant clothing)
should protect response personnel, providing
the conditions described in selecting Level A
are known or judged to be absent.
C. Level C Protection
Personnel protective equipment
Air-purifying respirator, full-face, canister-
equipped (MSHA/NIOSH approved)
Chemical-resistant clothing (includes:
coveralls or hooded, one-piece or two-piece
chemical splash suit or chemical-resistant hood
and apron; disposable chemical-resistant
coveralls)
Coveralls*, or
Long cotton underwear*
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*)
Escape mask*
2-Way radio communications (inherently safe)
(*) optional
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2. Criteria for selection
Meeting all of these criteria permits use of Level
C protection:
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 threshold 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 instruments such as the FID or PID. (See
Appendices I and II.)
3. Guidance on selection
a. Level C protection is distinguished from Level
B 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
atmospheric concentrations and other selection
criteria 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 remove the
substances encountered. Half-masks or cheek
cartridge equipped, full-face masks should be
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used only with the approval of a qualified
health and safety professional.
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.
• Site operations are not likely to generate
unknown compounds or excessive
concentrations of already identified
substances.
An air surveillance program is part of all
response operations when atmospheric
contamination is known or suspected. It is
particularly important that the air be
thoroughly monitored when personnel are wearing
air-purifying respirators. Periodic
surveillance using direct-reading instruments
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 respirator 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 respirator met. 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 or 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.
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The presence of particulates in air.
The errors associated with both the
instruments and monitoring procedures
used.
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.
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 concentrations of organic vapors
or gases in air approaching or exceeding
a few ppm above background require, as a
minimum, Level B protection.
D. Level D Protection
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*)
Escape mask*
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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 worn 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
protective equipment is one of the first steps in reducing
health effects from toxic substances. Until the toxic hazards
at an incident can be identified and personnel safety measures
commensurate with the hazards instituted, preliminary safety
requirements must be based on experience, judgment, and
professional knowledge.
Of primary concern in evaluating unknown situations are
atmospheric hazards. Toxic concentrations (or potential
concentrations) of vapors, gases, and particulates; low oxygen
content; explosive potential; and the possibility of radiation
exposure all represent immediate atmospheric hazards. In
addition to making air measurements to determine these
hazards, visual observation and review of existing data can
help determine the potential risks from other materials.
Once immediate hazards, other than toxic substances have been
eliminated, the initial on-site survey and reconnaissance
continues. Its purpose is to further characterize toxic
hazards and, based on these findings, refine preliminary
safety requirements. As data is obtained from the initial
survey, the Level of Protection and other safety procedures
are adjusted. Initial data also provide information upon
which to base further monitoring and sampling requirements.
No one method can determine a Level of Protection in all
unknown environments. Each situation must be examined
individually.
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IV., ADDITIONAL CONSIDERATIONS FOR SELECTING LEVELS OF PROTECTION
Other factors which should be considered in selecting the
appropriate 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 protective clothing greatly reduces
natural ventilation and diminishes the body's 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 be a contributing
factor to heat stress. Greater susceptibility to heat
stress occurs when protective clothing requires the use
of a tightly fitted hood against the respirator face
piece, or when gloves or boots are taped to the suit. As
more body area is covered, less cooling takes place,
increasing the probability of heat stress. Whenever any
chemical-protective clothing is worn, a heat stress
recovery monitoring program must occur. (See Part 7,
Stress).
Wearing protective equipment also increases the risk of
accidents. It is heavy, cumbersome, decreases dexterity,
agility, interferes with vision, and is fatiguing to
wear. These factors all increase physical stress and the
potential for accidents. In particular, the necessity of
selecting Level A protection should be balanced against
the increased probability of heat stress and accidents.
Level B and C protection somewhat reduces accident
probability because the equipment is lighter, less
cumbersome, and vision problems are less serious.
B. Air Surveillance
A program must be established for routine, periodic air
surveillance. Without an air surveillance program, any
atmospheric changes could go undetected and. jeopardize
response personnel. Surveillance can be accomplished
with various types of air pumps and filtering devices
followed by analysis of the filtering media; portable
real-time monitoring instruments located strategically
on-site; personal dosimeters; and periodic walk-through
by personnel carrying direct-reading instruments. (See
Part 10, Air Surveillance).
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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 automatically warrant a fully
encapsulating suit. A hooded, high quality, chemical-
resistant suit may provide adequate protection. The
selection of Level A over Level B is a judgment that
should be made by a qualified individual considering the
hazards and risk.
Hazards; The physical form of the potential contaminant
must be considered. Airborne substances are
more likely to contact personnel wearing non-
encapsulating suits, which are not considered
gas or vapor tight. Liquids contacting the skin
are generally considered more hazardous than
contact with vapors, gases and particulates.
Effect of the contaminant on skin:
highly hazardous substances are those that
are easily absorbed through the skin
causing systemic effects, or that cause
severe skin destruction.
less hazardous substances are those that
are not easily absorbed through the skin
causing systemic effects, or that do not
cause severe skin destruction
Risk; Concentration of the contaminant: The higher
the concentration, the higher the probability
of injury.
Work function: Site work activities dictate
the probability of direct and indirect skin
contact.
Instability of the situation: A higher Level
of Protection should be considered when there
is a probability of a release involving vapor
or gases, splashes or immersion in liquids, or
through the loss of container integrity.
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D. Atmospheric Conditions
Atmospheric conditions such as stability, temperature,
wind direction and wind velocity, as well as barometric
pressure determine the behavior of contaminants in air
or the potential for volatile material being released
into the air. These parameters should be considered when
determining the need for and Level of Protection
required.
E. Work in the Exclusion Zone
For operations in the Exclusion Zone (area of potential
contamination), different Levels of Protection may be
selected, and various types of chemical-resistant
clothing worn. This selection would be based on measured
air concentrations, the job function, the potential for
skin contact or inhalation of the materials present, and
ability to decontaminate the protective equipment used.
(See Part 8, Site Control - Work Zones).
G. Escape Masks
Carrying an escape, self-contained breathing apparatus
of at least five minute duration, is optional in while
wearing Level C or Level D protection. For initial site
entry, a specialist should determine, on-a-case-by basis,
whether they should be carried, or be strategically
located in 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 correctly, they are
deflections of the needle on the dial indicating cin instrument
response and do not directly relate to the total concentration
in the air. As a guide to selecting Levels of Protection,
based on dial readings, the following values could be used.
They must not be used as the sole criteria for selecting
Levels of Protection.
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PART 7
STRESS
I. INTRODUCTION
Both physiological and psychological stress effect response
personnel. Working in adverse weather conditions, wearing
chemical protective clothing, close proximity to hazardous
materials, and for some emergency responders working in life-
threatening situations, all contribute to physical strain and
possibly mental anxiety. Under certain conditions, stress
significantly contributes to worker accidents and illnesses.
To reduce.the potential for abnormal physical stress or mental
anxiety:
Workers must be periodically examined by a physician to
determine if they are physically and psychologically fit
to perform their jobs.
Continual practice and training must be provided in using
personnel protective equipment (especially self-con-
tained breathing apparatus and chemical-resistant
protective clothing).
An effective safety program must be established and a
dedicated effort made to protect the worker. These
actions will help assure personnel that their health and
safety will be protected now and in the future.
II. WEATHER
Adverse weather conditions are important considerations in
planning and conducting site operations. Hot or cold weather
can cause physical discomfort, loss of efficiency, and
personal injury. Of particular importance is heat stress
resulting from protective clothing decreasing natural
ventilation of the body. Heat stress can occur even when
temperatures are considered 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, drink plenty of
water, commercial drink mixes along with more heavily
salted foods (unless on a low salt diet). To prevent
dehydration, response personnel should be encouraged to
drink generous amounts of water even if not thirsty.
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Heat-related problems can happen before the sensation of
thirst occurs.
Provide cooling devices to aid natural body ventilation.
These devices, however, add weight, and their use should
be balanced against worker fatigue. Long cotton
underwear or similar type garments act as a wick to help
absorb moisture and protect the skin from direct contact
with heat-absorbing chemical 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.
Ensure that adequate shelter is available to protect
personnel against heat, cold, rain, snow, and that a
shaded resting area is provided on sunny days. On hot
days, air conditioned rest areas should be provided.
In hot weather, rotate teams of workers wearing
protective clothing or performing extremely arduous
tasks. In extremely hot weather, conduct non-emergency
response operations in the early morning or evening.
Response personnel should be encouraged to maintain their
physical fitness. Physically fit personnel are less prone
to stress-related problems.
Liquids which act as diuretics (such as alcohol and
coffee) should be avoided or their intake minimized prior
to anticipated operations. These can contribute to
dehydration and subsequent heat-related problems.
III. HEAT STRESS MONITORING
For monitoring the body's recuperative ability to handle
excess heat, one or more of the following techniques should
be used as a screening technique. 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 Fahrenheit workers must be
monitored for heat stress after every work period.
Heart rate (HR) should be measured by counting 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
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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 clothing 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 to replace the water lost through
perpiration. Ideally, body fluids should be maintained
at a constant level during the work day. This requires
replacement of salt lost in sweat as well.
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.
IV. 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, irritability, 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.
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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 meet increased 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. Can be
fatal. Medical help must be obtained immediately. Body
must be cooled immediately to prevent severe injury
and/or death. Signs: red, hot, dry skin; no perspiration;
nausea; dizziness and confusion; strong, rapid pulse;
coma.
V. 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.
Two factors influence the development of a cold weather
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.
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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. It can be fatal. Its symptoms
are usually exhibited in five stages: 1) shivering, 2) apathy,
listlessness, 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.
VI. SUMMARY
Physiological and psychological stress can effect response
personnel. These stresses occur in a number of ways. Persons
responsible for health and safety programs must be aware that
response personnel may be working under conditions that are
conducive in causing stressful situations and make every
effort to minimize the problems.
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PART 8
SITE CONTROL - WORK ZONES
I. INTRODUCTION
The activities required during responses to incidents
involving hazardous substances may contribute to the unwanted
movement of contaminants 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 to the
disturbance of contaminated soil causing 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 personnel 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 site security 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 personnel and equipment and to eliminate the potential
for airborne dispersion.
Implementing decontamination procedures.
8-1
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V>EPA ENVIRONMENTAL RESPONSE TEAM
_>
8-2
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III. 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 itself would be
limited by access control points. Three contiguous zones
(Figure 8-1) are recommended:
Zone 1: Exclusion Zone
Zone 2: Contamination Reduction Zone
Zone 3: Support Zone
A. Zone 1: Exclusion Zone
The Exclusion Zone, the innermost of three areas, is the
physical area where contamination does or could occur.
All people entering the Exclusion Zone must wear
prescribed Levels of Protection. Entry and exit check
points must be established at the periphery of the
Exclusion Zone to regulate the flow of personnel and
equipment into and out of the zone and to verify that the
procedures established to enter and exit are followed.
The outer boundary of Zone 1, the Hotline, is initially
established by visually surveying the immediate vicinity
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 inorganic
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.
8-3
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B. 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
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 8-2). The Level of Protection is
determined by the measured concentration of substances
in air, potential for contamination, and the known or
suspected presence of toxic substances.
The job assignment or the type of work to be done might
also dictate the Levels of Protection to be worn. 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, is
considered a non-contaminated or clean area. Support
equipment (command post, equipment trailer, etc.) is
located in the zone; traffic is 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;
location of highways; railroad tracks; or other
limitations.
Wind Direction: Preferably the support facilities
should be located upwind of the exclusion Zone.
However, shifts in the wind and other conditions
may be such that an ideal location based on wind
direction alone does not exist.
8-4
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Resources: Adequate roads, power lines, water, and
shelter should be available in close proximity to
the site.
D. Zone 2: Contamination Reduction Zone
Between the Exclusion Zone and the Support Zone is the
Contamination Reduction Zone which provides a transition
between contaminated 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 contaminated substances on
people, equipment, or in the air is limited through a
combination of decontamination, distance between the
Exclusion and Support Zones, air dilution, zone
restrictions, and work functions.
Initially, the Contamination Reduction Zone is considered
a non-contaminated area. At the boundary between the
Exclusion and Contamination Reduction Zones,
Contamination Reduction Corridors (consisting of an
appropriate number of decontamination stations) are
established, one for personnel and one for heavy
equipment. Depending on the size of the operation, more
than two corridors may be necessary. Exit from the
Exclusion Zone is through a Contamination Reduction
Corridor. As operations proceed, the area around the
contamination station may become contaminated, but to a
much lesser degree than the 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 Reduction Zone, the Contamination Control
Line, separates the possibly low contamination area from
the clean Support Zone. Access to the Contamination
Reduction Zone from the Support Zone is through a control
point. Personnel entering this zone should wear the
prescribed personnel protective equipment, if required,
for working in the Contamination Reduction Zone. Entering
the Support Zone requires the removal of any protective
equipment worn in the Contamination Reduction Zone.
8-5
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IV. OTHER CONSIDERATIONS
A. The use of the three-zone system, access control points,
and exacting decontamination procedures, provides a
reasonable assurance against the translocation of
contaminating substances. This site control system is
based on a worst case situation. Less stringent site
control and decontamination procedures may be utilized
if more definitive information is available on the types
of substances involved and the hazards they present. This
information can be obtained through air monitoring,
instrument survey and sampling, along with available
technical information concerning the characteristics and
behavior of the 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 8-2 and 8-3). Considerable 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 possibility of injury due
to explosions or fires. Long-term operations would
involve developing reasonable methods (for example, air
surveillance, swipe testing, and visible deterioration)
to determine if material is being transferred between
zones and to assist in modifying site boundaries.
The following criteria should be considered in
establishing area dimensions and boundaries:
Physical and topographical features of the site.
Weather conditions.
Field/laboratory measurements of air contaminants
and environmental samples.
Air dispersion calculations.
Physical, chemical, toxicological, and other
characteristics of the substances present.
Cleanup activities required.
Potential for fire.
8-6
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size of 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 by collecting air samples
for particulate, gas or vapor analysis. Analysis of soil
samples collected in the most heavily trafficked areas
would indicate contaminants being carried from the
Exclusion Zone by personnel, equipment, wind, or surface
water runoff. Occasional swipe tests should be taken in
trailers and other areas used by personnel.
These same types of samples should be collected and the
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.
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ENVIRONMENTAL RESPONSE TEAM
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8-9
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PART 9
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 sitting
or kneeling on contaminated soil.
Using contaminated instruments or equipment.
Protective clothing and respirators help prevent the wearer
from becoming contaminated or inhaling contaminants. Good work
practices help reduce contamination on protective clothing,
instruments, and equipment.
Even with these safeguards, contamination may occur. Harmful
materials can be transferred to clean areas, exposing
unprotected personnel. During removal of contaminated
clothing, personnel may contact contaminants on their clothing
or inhale them. To prevent such occurrences, methods to reduce
contamination, and decontamination procedures must be
developed and established before anyone enters a site and must
continue (modified when necessary) throughout site operations.
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 equipment, and the use of site work zones
minimizes cross contamination from protective clothing to
wearer, equipment to personnel, and from 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.
9-1
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II. PRELIMINARY CONSIDERATIONS
A. Initial Planning
The initial decontamination plan assumes all personnel
and equipment leaving the Exclusion Zone (area of
potential contamination) are grossly contaminated. A
system is then set up for personnel decontamination to
wash and rinse, at least once, all the protective
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 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
situation 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.
9-2
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Type of equipment needed to accomplish the work
task.
The initial decontamination plan is modified, eliminating
unnecessary 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 disposable boot covers and
gloves could eliminate washing and rinsing these items
and reduce the number of stations needed. Changes in the
decontamination procedure must be noted in the Site
Safety Plan.
B. 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,
overall dimensions of work control zones, and amount of
space available at the site. A corridor of 75 feet by 15
feet is the minimum area for full decontamination.
Whenever possible, it should 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 personnel, 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.
9-3
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FIGURE 9-1
V>EPA ENVIRONMENTAL RESPONSE TEAM
9-4
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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 exhibit the same degree of
toxicity (or other hazard). Whenever 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 downgraded.
2. Amount of Contamination
The amount of contamination on protective clothing
(and other objects or equipment) is usually
determined visually. If, on visual examination, it
appears grossly contaminated, a thorough
decontamination is generally required. Gross
material remaining on the protective clothing for
any extended period of time may degrade or permeate
it. This likelihood increases with higher air
concentrations and greater amounts of liquid
contamination. Gross contamination also increases
the probability 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 decontamination line. Each Level of
Protection incorporates different problems in
decontamination and doffing of the equipment. For
example: decontamination of the harness straps and
backpack assembly of the self-contained breathing
apparatus is difficult. A butyl rubber apron worn
over the harness makes decontamination easier.
Clothing variations and different Levels of
9-5
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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, photographers, operators of air
samplers, or others in the Exclusion 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 decontamination lines could be set up for
different job functions, or certain stations in 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.
B. Effectiveness of Decontamination
There is no method to immediately determine how effective
decontamination is. Discolorations, stains, corrosive
effects, and substances adhering to objects may indicate
contaminants have not been removed. However, observable
effects only indicate surface contamination and not
9-6
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permeation (absorption) into clothing (tools or
equipment). Also many contaminants are not easily
observed.
A method for determining effectiveness of surface
decontamination is swipe, or wipe 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. Determining permeation of
contaminants into protective garments requires laboratory
analysis of a piece of the material. Both swipe and
permeation testing provide after-the-fact information.
Along with visual observations, results of these tests
can help evaluate the effectiveness of decontamination.
In many cases, depending on the substances involved,
chemical protective clothing (or naturally absorbable
materials) may have to be discarded. If it cannot be
determined that clothing or other items, for example,
tools and equipment have been completely decontaminated,
the only safe action is to consider them hazardous wastes
and have them disposed of properly.
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. Contaminated 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
equipment are usually decontaminated by scrubbing with
detergent-water using a soft-bristle brush followed by
9-7
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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 decori chemical is
then needed that will change the contaminant into a less
harmful substance. Especially troublesome are unknown
substances or mixtures from a variety of known or unknown
substances. The appropriate decontamination solution must
be selected in consultation with an experienced chemist.
E. Establishment of Procedures
Once decontamination procedures have been established,
all personnel requiring decontamination must be given
precise instructions (and practice, if necessary).
Compliance must be frequently checked. The time it takes
for decontamination must be ascertained. Personnel
wearing SCBAs must leave their work area with 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. Planning should include:
Training of response team members in advanced first
aid and emergency lifesaving methods.
Arranging with the nearest medical facility for
transportation and treatment of injured, and for
treatment of personnel suffering from exposure to
chemicals.
Providing consultation services with toxicologists
and other medical specialists.
Having at the incident specialized equipment, for
example, emergency eye washes, showers, first aid
kits, blankets, stretcher, and a resuscitator.
In addition, the plan should establish procedures for
decontaminating personnel with medical problems and
injuries. There is the possibility that decontamination
may aggravate or cause more serious health effects. If
9-8
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life threatening injuries are received, prompt life-
saving first aid and medical treatment should be
administered without decontamination, or concurrently
with it. Whenever possible, response personnel should
accompany 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.
Life-saving care should be instituted immediately without
considering decontamination. The outside garments can be
removed (depending on the weather) if they do not cause
delays, interfere with treatment, or aggravate the
problem. Respirators and backpack 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 individual should be wrapped in plastic,
rubber, or blankets to help prevent contaminating the
inside of ambulances and medical personnel. 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 if it 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 is obviously
contaminated, decontamination should be omitted or
minimized and treatment begun immediately.
9-9
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D. Chemical Exposure
Exposure to chemicals can be divided into two categories:
Injuries from direct contact, such as acid 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 is on the skin
or in the eyes, immediate measures must be taken to
counteract the substance's effect. First aid treatment
usually is flooding the affected area with water;
however, for a few chemicals, water may cause more severe
problems.
When protective clothing is 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.
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.
Particulates 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
9-10
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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
unknowns, highly volatile liquids, or highly toxic
materials, decontamination workers should wear Level B
protection.
Level B protection includes SCBA, hard hat with face
shield, chemical-resistant gloves and boots, 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. DECONTAMINATION OF EQUIPMENT
Insofar as possible, measures should be taken to prevent
contamination of sampling and monitoring equipment. Sampling
devices become contaminated, but monitoring instruments,
unless they are splashed, usually do not. Once contaminated,
instruments are difficult to clean without damaging them. Any
delicate instrument which cannot be easily decontaminated
should be protected while it is being used. It 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 and exhaust.
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 chemicals. They should be kept on site
9-11
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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. Respirators
Certain parts of contaminated respirators, such as
the harness assembly and straps, 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 responsible
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 or to scrub
accessible parts with detergent/water solution under
pressure. 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. Personnel doing the decontamination
must be adequately protected for the methods used
can generate contaminated mists and aerosols.
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 manufacturer's instructions should be
used to sanitize the respirator mask. If practical,
protective clothing should be machine washed (in a
dedicated unit) after a thorough decontamination;
otherwise they must be cleaned by hand.
C. Persistent Contamination
In some instances, clothing and equipment will become
contaminated with substances that cannot be removed by
normal decontamination procedures. A solvent may be used
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to remove such contamination from equipment if it does
not destroy or degrade the protective material. If
persistent contamination is expected, disposable garments
should be used. Testing for persistent contamination of
protective clothing and appropriate decontamination 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 decontaminated on-site 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 4, 5, and 6 describe basic decontamination procedures
for a worker wearing Level A, B, or C protection. The basic
decontamination lines (Situation I), consisting of
approximately 19 stations, are almost identical except for
changes necessitated by different protective clothing or
respirators. For each annex, three specific situations are
described in which the basic (or full decontamination)
procedure is changed to take into account differences in the
extent of contamination, the accompanying changes in 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 7 describes a minimum layout for Level A personnel
decontamination. The number of individual stations have been
reduced. Although the decontamination equipment and amount of
space required is less than needed in the procedures
previously described, there is also a much higher probability
of cross-contamination.
A4-1
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ANNEX 4
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-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
A4-1
-------
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
A4-2
-------
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; 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
A4-3
-------
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.
A4-4
-------
Equipment:
water
soap
small table
basin or bucket, or
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 (SITUATION 1) AND THREE MODIFICATIONS
(SITUATION 1, 2, AND 3)
SIT.
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
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.
A4-5
-------
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 will return to Exclusion Zone.
A4-6
-------
ZONE
OUTER GLOVE
REMOVAL
r^ r"^
[6 }• (s)
\
BOOT
TAPE
REMOVAL
X
« — T
' BOOT COVER
REMOVAL
~> x^
4J* 13
COVER
&
GLOVE WASH ,
•< s
V
BOOT COVER &
GLOVE
RINSE
^x xS SEGREGATED
2 h f 1 J EQUIPMENT
^'^ ^^ DROP
x -•• x HOTLINE
TANK CHANGE 9 K
SUIT/SAFETY BOOT
WASH
SUIT/SAFETY BOOT
RINSE
SAFETY BOOT
REMOVAL
CONTAMINATION
REDUCTION
ZONE
11
12
13
FULLY ENCAPSULATING SUIT
AND HARD HAT REMOVAL
SCBA BACKPACK
REMOVAL
INNER GLOVE
WASH
DECONTAMINATION LAYOUT
LEVEL A PROTECTION
14
INNER GLOVE
RINSE
15
FACE PIECE
REMOVAL
16
INNER GLOVE
REMOVAL
FIELD
WASH
18
INNER CLOTHING
REMOVAL
-H19 REDRESS
FIGURE A4-1
SUPPORT
ZONE
4>ER/\ ENVIRONMENTAL RESPONSE TEAM
A4-7
-------
ANNEX 5
LEVEL B DECONTAMINATION
A. EQUIPMENT WORN
The full decontamination 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
A5-1
-------
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 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
A5-2
-------
small buckets
sponges or cloths
Station 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
high-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.
A5-3
-------
Equipment: - container (30-50 gallons)
plastic liners
bench or stool
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 tiroes 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 liners
A5-4
-------
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.
Equipment:
water
soap
small tables
basins or buckets, or
field showers
Station 19; Redress
Put on clean clothes.
inclement weather.
A dressing trailer is needed in
Equipment:
tables
chairs
lockers
clothes
C. FULL DECONTAMINATION (SITUATION 1) AND THREE MODIFICATIONS
(SITUATION 1, 2, AND 3)
SIT.
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
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.
A5-5
-------
Situation 2; Same as Situation 1 except individual needs new air
tank and will return to Exclusion Zone.
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 will return to Exclusion Zone.
A5-6
-------
tJ
OUTER GLOVE
REMOVAL
,x\ /^,
[6 }• [ 5
iULU£>IUIN
ZONE
TAPE
REMOVAL
^S
"• 4 r« 1
\X l
BOOT COVER BOOT
BOOT COVER
&
GLOVE WASH <
X\ ,/\, ^
^ SEGREGATED
3 J* [ 2 U [ 1 I EQUIPMENT
"^ ^^ \^ DROP
COVER &
REMOVAL GLOVE RINSE
v v v y. y. WC\T\ IMP
TANK CHANGE
CONTAMINATION
REDUCTION
ZONE
SUIT/SAFETY BOOT
WASH
SUIT/SCBA/BOOT/GLOVE
" " -'" 1 O I
MCH
MlJ
ION 1
N M
MS]
M4J
M5J
M6J
RINSE
SAFETY BOOT
REMOVAL
SCBA BACKPACK
REMOVAL
SPLASH SUIT DECONTAMINATION LAYOUT
REMOVAL LEVEL B PROTECTION
INNER GLOVE
WASH
INNER GLOVE
RINSE
FACE PIECE
REMOVAL
INNER GLOVE
REMOVAL
17
INNER CLOTHING
REMOVAL
.^.—.—.—.—.-^.—.—.—.—.—.—.-COH™,,™-,...
FIELD
WASH
-»l9 REDRESS
FIGURE A5-1
SUPPORT
ZONE
V>EPA ENVIRONMENTAL RESPONSE TEAM
A5-7
-------
ANNEX 6
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.
Equipment: - container (20-30 gallons)
decon solution or
detergent water
2-3 long-handle, soft-bristle scrub-
brushes
A6-1
-------
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
A6-2
-------
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; 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.
A6-3
-------
Equipment: - decon solution or
detergent/water
basin or bucket
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, or
A6-4
-------
field showers
Station 18; Redress
Put on clean clothes.
inclement weather.
A dressing trailer is needed in
Equipment:
tables
chairs
lockers
clothes
C. FULL DECONTAMINATION (SITUATION 1) AND THREE MODIFICATIONS
( SITUATION 2, 3, & 4)
SIT.
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.
A6-5
-------
r
OUTER GLOVE
REMOVAL
EXCLUSION
ZONE
TAPE
REMOVAL
BOOT COVER
&
GLOVE WASH
CANISTER OR
MASK CHANGE
BOOT COVER BOOT COVER &
REMOVAL GLOVE RINSE
SEGREGATED
1 ] EQUIPMENT
DROP
x-HOTLINE-x-
CONTAMINATION
REDUCTION
ZONE
11
12
13
.A ,
4
SUIT/SAFETY BOOT
WASH
SUIT/SAFETY BOOT
RINSE
SAFETY BOOT
REMOVAL
SPLASH SUIT
REMOVAL
INNER GLOVE
WASH
INNER GLOVE
RINSE
FACE PIECE
REMOVAL
DECONTAMINATION LAYOUT
LEVEL C PROTECTION
15 I INNER GLOVE
' REMOVAL
. INNER CLOTHING
16 I REMOVAL
.._._._.^._.__™_._._«g™J5«.0,L_..
FIELD
WASH
-H18 REDRESS
SUPPORT
ZONE
FIGURE A6-1
V>EPA ENVIRONMENTAL RESPONSE TEAM
A6-6
-------
ANNEX 7
LEVEL A DECONTAMINATION, MINIMUM LAYOUT
A. EQUIPMENT WORN
The decontamination procedure outlined is for workers wearing
Level A protection (with taped joints between 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 decon solution or detergent water. Rinse off using
copious amounts of water.
Equipment: - containers (30-50 gallons)
decon solution or
detergent water
rinse water
2-3 long-handle, soft-bristle scrub-
brushes
A7-1
-------
Station 3; Outer Boot and Glove Removal
Remove outer boots and gloves. Deposit in container with
plastic liner.
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:
air 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
A7-2
-------
Station 7: Field Wash
Thoroughly wash hands and face. Shower as soon as possible,
Equipment: - water
soap
tables
wash basin/bucket
A7-3
-------
r
TANK
CHANGE
CONTAMINATION
REDUCTION
ZONE
o o-
EXCLUSION
ZONE
SEGREGATED EQUIPMENT
DROP
x-HOTLINE- x-
OUTER GARMENT, BOOTS, AND
GLOVES WASH AND RINSE
OUTER BOOT AND
GLOVE REMOVAL
MINIMUM
DECONTAMINATION LAYOUT
LEVEL A PROTECTION
BOOTS, GLOVES, AND
OUTER GARMENT
REMOVAL
SCBA REMOVAL
CONTAMINATION
CONTROL LINE
0
7 1 FIELD WASH
SUPPORT
ZONE
FIGURE A7-1
ENVIRONMENTAL RESPONSE TEAM
A7-4
-------
PART 10
AIR SURVEILLANCE
I. INTRODUCTION
Accidents involving hazardous materials or remedial actions
at abandoned 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 personnel and the public.
Hazardous atmospheres can involve:
Ignitable or explosive vapors, gases, aerosols, and dusts
(explosive atmosphere).
Toxic vapors, gases, and aerosols (toxic atmosphere).
Displacement of breathable air (oxygen-deficient
atmosphere).
Radioactive materials (radioactive environment).
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 personnel.
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
5, Initial Site Survey and Reconnaissance, regarding initial
characterization 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).
10-1
-------
The objective of air surveillance during response is to
identify and quantify airborne contaminants on and off-site,
and monitor changes in air contaminants that occur over the
lifetime of the incident.
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.
Accomplishing 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 container, etc.), and other information
(manifests, railroad consists, inventories, government 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; Includes chemical fires,
spills, or other releases of hazardous materials which
occur over a relatively 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; Includes planned removals and
remedial actions at abandoned 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 long term cleanup activities require more
time (and planning) to accomplish, appropriate equipment
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for air monitoring and sampling 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. These changes can include
start-up of work in a different part of the site, discovery
of contaminants other than those expected, and initiation of
different types of work. Surveillance for vapors, gases, and
particulates is done using DRIs and air sampling systems.
DRIs can be used to detect many organics and a few inorganics
and provide approximate 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 however, only air
sampling (and laboratory 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 reguired to obtain results.
Analyzing large numbers of samples in laboratories is very
expensive, especially if results are needed 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
utilizing 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/quantitative 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 real-time 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 8.
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V. AIR SAMPLING STRATEGIES
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 various
locations throughout the area. These samples provide air
quality information for the period of time they operate, and
can indicate contaminant 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 DRIs 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, and any other
potential source of contaminants, 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.
Contamination Reduction Zone - Air samples should be
collected along the decontamination line to ensure that
decontamination personnel 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 or source areas detected by DRIs,
types of substances 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
personnel protection, set exclusion zone boundaries, as
well as to provide a continual record of air
contaminants.
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Downwind - Sampling stations are located downwind from
the site to determine if any air contaminants are
migrating from the site. If there are indications of
airborne hazards in populated areas, additional samplers
should be placed downwind.
VI. MEDIA FOR COLLECTING AIR SAMPLES
Hazardous material incidents, especially abandoned waste
sites, involve many potentially dangerous substances including
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 sorbent
for most organic vapors. However, other solid sorbents
(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
samples are collected using an industrial hygiene
personal sampling pump with either one sampling port or
a manifold system capable of simultaneously collecting
samples on several sorbent tubes. Individual pumps with
varying flow rates may also be used to collect several
samples at once. 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 substances (such as high-molecular-weight
hydrocarbons, organophosphorus compounds, and the
vapors of certain pesticides) that adsorb poorly
onto activated carbon. Some of these porous
polymers also adsorb organic materials at low
ambient temperatures 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.
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Any other specialty adsorbent selected for the
specific site. For example, a Florisil tube could
be used if polychlorinated biphenyls are suspected.
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 chromatography. Impingers
filled with selected liquid reagents can also be used.
Aerosols: Aerosols (solid or liquid particulates) that
may be encountered at an incident include contaminated
and non-contaminated 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 1-3, 2nd. &
3rd. Editions) contains acceptable methods for collecting 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 collection 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, 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
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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 exhaustively
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 adsorbents and sampling
conditions can be used for specific PHCs if desired while
continued multimedia sampling provides 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 dosimeters. The few 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:
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Diffusion samplers, in which molecules move across
a concentration gradient, usually achieved within
a stagnant layer of air, between the contaminated
atmosphere and the indicator material.
Permeation devices, which rely on the natural
permeation of a contaminant through a membrane. A
suitable membrane is selected thcit 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 similar 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. Representative workers are equipped with
personal samplers to indicate contaminants at specific
locations or for specific work being done. Placed in workers
breathing zone, generally within 1 foot of the mouth and nose,
the monitors indicate the potential for the worker to inhale
the contaminant.
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. At 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 recalibrated after
repair, when newly purchased, and following suspected abuse.
Calibration methods can be found in the NIOSH Manual of
Analytical Methods.
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X. METEOROLOGICAL 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, are needed for:
Selecting air sampling locations.
Calculating air dispersion.
Calibrating instruments.
Determining population at risk or environmental exposure
from airborne contaminants.
Knowledge of wind speed and direction is necessary to
effectively place air samplers. It is particularly important
in source-oriented ambient air sampling that samplers be
located at varying distances downwind from the source, as well
as to collect background air samples upwind from the source.
Shifts in wind direction must be known and samplers relocated
or corrections made for the shifts. In addition, atmospheric
simulation models for predicting contaminant dispersion and
concentration need windspeed and direction as inputs for
predictive calculations. Information may be needed concerning
the frequency and intensity of winds from certain directions
(windrose 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 data on air temperature and pressure during sampling.
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 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
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obtain meteorological equipment, accuracy of information
needed, and the use of the information.
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ANNEX 8
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, developed and used by the
U.S. EPA 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 chromatograph (GC)
capabilities of field instruments. Selected samples
are also analyzed in laboratories accredited by the
American Industrial Hygiene Association (AIHA).
A8-1
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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.
Sampling for particulates, inorganic acids, aromatic
amines, halogenated 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. Other equivalent equipment can be
substituted:
HNU Systems Photoionizer (PID)*
Foxboro OVA (FID)*
Photovac GC*
Gillian Model Number HFS-UT113 Sampling Pump*
Tedlar Bags (0.5 liters)*
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.
(*) The use of brand names does not imply their endorsement
by the U.S. EPA
A8-2
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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 determine if contaminants are leaving the
site.
Concentrations on-site. The on-site area is monitored (using
DRIs) for total gas/vapor concentrations, 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).
Transient contributors on-site, for example, exhausts from
engines, should be avoided. Concentrations are recorded and
plotted on a site map. Additional DRI monitoring is then done
to thoroughly define any 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 hotspots (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 afternoon respectively, using personal sampling pumps
equipped with Tenax and/or carbon-packed, metal adsorption
tubes. Total gas/vapor concentration (using DRI) 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 either collected on media, and desorbed with a
thermal desorber or collected in air bags. Samples are then
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analyzed by a field gas chromatograph (PID or FID) 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.
If relatively high concentrations of chemicals are detected
by the initial DRI surveys samplers equipped with carbon-
packed collection tubes (glass) and Tenax/carbon-packed
(metal) tubes are operated. The latter samples are analyzed
in the field. The carbon-packed collection 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 activities. 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 operated 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 the morning samples), 100-150
mg carbon-packed tubes (glass) are used and operated at a flow
rate of 500 cubic centimeters/minute until approximately 100
liters of air have been collected. Depending on suspected
contaminants and their concentrations, higher flow rates
and/or volumes maybe 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
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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 to 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 to collect
additional samples for laboratory analysis.
If desorption equipment is not available for on-site sample
analysis, glass collection tubes or grab samples using a
desiccator and tedlar bag setup, should be obtained daily.
Samples are then analyzed using a field GC. Only samples
collected every third to fifth day are sent to AIHA accredited
laboratories 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 patterns. 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 Analytical Method No. 1003, 1500, and 1501 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 should be consulted
for the appropriate collection media and flow rates.
Particulates and Inorganic Gases and Vapors. Sampling for
particulates is not done routinely. If these types of air
contaminants are known or suspected to be present, a sampling
program is instituted for 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 that create dust
(from contaminated soil and excavation of contaminated soil).
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Sampling media and analytical methods for these air
contaminants should follow guidance given in the NIOSH Manual
of Analytical Methods.
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APPENDIX I
CHARACTERISTICS OF THE HNU PHOTOIONIZER
AND
ORGANIC VAPOR ANALYZER
I. INTRODUCTION
The HNU Photoionizer* and the Foxboro Organic Vapor Analyzer*
(OVA) are used in 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 monitoring 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 retention 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 into
the column from the air sampling hose or injected directly
with a gas-tight syringe.
(*) The use of any trade names does not imply their
endorsement by the U.S. Environmental Protection Agency.
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ACTION
TABLE I-I
COMPARISON OF THE OVA AND HNU
OVA
HNU
Response
Application
Responds to many organic gases
and vapors.
In survey mode, measures total
concentration of detectable
gases and vapors. In GC mode,
identifies and measures
specific compounds.
Responds to many organic
and some inorganic gases
and vapors.
In survey mode, measures
total concentration of
detectable gases and
vapors.
Detector
Limitations
Flame ionization detector (FID)
Does not respond to inorganic
gases and vapors. Kit available
for temperature control.
Calibration gas Methane
Ease of
operation
Requires experience to inter-
pret correctly, especially
in GC mode.
Photoionization detector
(PID)
Does not respond to
methane. Does not detect
a compound if probe has a
lower energy than
compound's ionization
potential.
Isobutylene
Fairly easy to use and
interpret.
Detection limits 0.1 ppm (methane)
Response time
Maintenance
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
batteries after each use.
0.1 ppm (benzene)
3 seconds for 90% of
total concentration of
benzene.
Clean UV lamp frequently..
Check calibration
regularly. Recharge
batteries after each
use.
Useful range
Service life
0-1000 ppm
8 hours; 3 hours with strip
chart recorder.
0-2000 ppm
10 hours; 5 hours with
strip chart recorder.
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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
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 measuring 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 characteristic 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 transformed
into charged ion pairs, creating a current between two
electrodes.
Three probes, each containing a different UV light source,
are available 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
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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 the lamp's service life is longer than the 11.7 eV probe
and it detects more compounds than the 9.5 eV probe.
The 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.
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
possibilities. Noting instrument response to a contaminant
source with different probes can eliminate some contaminants
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 or inorganic
compounds.
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 atmosphere and does not detect methane.
"V. 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
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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) is 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.
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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 contaminants 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, infectious wastes, or other substances that do
not elicit an instrument response may be known or suspected
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 from the chemical and toxicological
characteristics of the known or suspected material.
II. FACTORS FOR CONSIDERATION
In utilizing total atmospheric vapor/gas concentrations as a
guide for selecting a Level of Protection, a number of other
factors should also be considered:
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The uses, limitations, and operating characteristics of
the monitoring instruments must be recognized and
understood. Instruments such as the HNU Photoionizer,
Foxboro Organic Vapor 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 Threshold Limit Value (TLV)
or Immediately Dangerous to Life and Health (IDLH) value
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 exposure, 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 such
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 respiratory protection program must be developed and
implemented according to recognized standards (ANSI
Z88.2-1980).
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III. LEVEL A PROTECTION (500 to 1,000 PPM ABOVE BACKGROUND)
Level A 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 following criteria:
Although Level A provides protection against air
concentrations greater than 1,000 ppm for most
substances, an operational restriction of 1,000 ppm is
established as a warning flag to:
Evaluate the need to enter environments with unknown
concentrations greater than 1,000 ppm.
Identify the specific chemical constituents
contributing to the total concentration and their
associated toxic properties.
Determine more precisely the concentrations of
constituent chemicals.
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 concentration was selected to fully protect the
skin until the constituents can be identified and
measured and substances affecting the skin excluded.
The range of 500 to 1,000 ppm is sufficiently
conservative to provide a safe margin of protection if
readings are low due to instrument error, calibration,
and sensitivity; if higher than anticipated
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
encountered on hazardous waste sites. High concentrations
have been encountered only in closed buildings, when
containers were being opened, when personnel were working in
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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 for 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.
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 concentrations 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.
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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 protection against inhalation hazards. A
range of background to 5 ppm above ambient background
concentrations of vapors/gases in the atmosphere has been
established as guidance for selecting Level C protection.
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
canister (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 TLVs or IDLH concentrations.
Many of the latter substances are gases or liquids in their
normal state. Gases would only be found in gas cylinders,
while the liquids would not ordinarily be found in standard
containers or drums.
Every effort should be made to identify the individual
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 exceedingly difficult, however, to provide
constant, real-time identification of all components, with
concentrations of a few parts per million, in a vapor cloud,
at a site where ambient concentrations are constantly
changing.
If highly toxic substances have been ruled out, but ambient
levels of a few parts per million persist, it is unreasonable
to assume only self-contained breathing apparatus should be
worn. The continuous use of air-purifying masks in vapor/gas
concentrations 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-
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purifying devices. The increased probability of exposure due
to the work being done may require Level B 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 appropriate Level of Protection, caution
should be used in the interpretation 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 composite 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 determine Levels of Protection should provide protection
against concentrations 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 constituents must be
identified as rapidly as possible and Levels of Protection
based on the toxic properties of the specific substances
identified.
VII. EXPLANATION OF PHRASE TOTAL ATMOSPHERIC VAPOR/GAS
CONCENTRATION
The phrase "total atmospheric vapor/gas concentration" is
commonly used to describe the readout, in ppm, on PIDs and
FIDs. 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 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.
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•ftU.S. GOVERNMENT PRINTING OFFICE! I 988 - 548 - I 5e/8701 2
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U.S. Environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevard, 12th Floor
Chicago, IL 60604-3590
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