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EPA-340/1-85-002a
Air Pollution Source Inspection
Safety Procedures
Student Manual
Prepared by
John Richards
Robin Segal
Engineering-Science, Inc.
501 Willard Street
Durham, N.C. 27701
Contract No. 68-01-6312
Task No. 126
EPA Project Officer: John R. Busik
EPA Work Assignment Managers:
Elva Slagle
Kirk Foster
Prepared for:
Occupational Health and Safety Staff
Office of Administration
and
Stationary Source Compliance Division
Office of Air Quality Planning and Standards
U.S. Environmental Protection Agency
Washington, DC 20460
September 1985
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INTENDED PURPOSE
This is not an official policy and standards document. The opinions,
findings, and conclusions are those of the authors and not necessarily those of
the Environmental Protection Agency. Every attempt has been made to represent
the present state of the art as well as subject areas still under evaluation.
Any mention of products or organizations does not constitute endorsement by the
United States Environmental Protection Agency.
This document is issued by the Stationary Source Compliance Division,
Office of Air Quality Planning and Standards, U.S. EPA. It is for use in
workshops presented by Agency staff and others receiving contractual or grant
support from the U.S. EPA.
Governmental air pollution control agencies establishing training programs
may receive single copies of this domument, free of charge, from the Stationary
Source Compliance Division Workshop Coordinator, U.S. EPA, MD-7, Research
Triangle Park, N.C. 27711. Since the document is specially designed to be used
in conjunction with other training materials and will be updated and revised
periodically as needed, it is not issued as an EPA publication nor copies
maintained for public distribution.
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TABLE OF CONTENTS
Lecture
1. INTRODUCTION
2. WALKING AND CLIMBING HAZARDS
3. HAZARDS TO VISION AND HEARING
4. BURN, ELECTRICAL AND EXPLOSION HAZARDS
5. HEAT AND COLD STRESS
6. INHALATION HAZARDS
7. SPECIAL INSPECTION SAFETY PROBLEMS
8. SAFE USE OF PORTABLE INSPECTION EQUIPMENT
9. AGENCY SAFETY PROGRAMS
APPENDIX A BIBLIOGRAPHY
APPENDIX B REVIEW QUESTIONS AND ANSWERS
APPENDIX C EXAMPLE OF ONE PLANT'S SUBSTANCE
EXPOSURE SYMPTOM CHART
APPENDIX D EXAMPLE HAZARD REPORTING FORM
APPENDIX E EPA RESPIRATORY PROTECTION PROGRAM GUIDELINE
Page Number
1
7
45
57
71
83
131
137
149
153
157
169
177
181
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DISCLAIMER
The safety precautions set forth in this manual and presented at any
training or orientation session, seminar, or other presentation using this
manual are general in nature. The precise safety precaution required for any
given situation depends upon and must be tailored to the specific circumstances
or each situation. Engineering-Science, Inc. expressly disclaims any liability
for any personal injuries, death, property damage, or economic loss arising
from any actions taken in reliance upon this manual or any training or
orientation session, seminar, or other presentation based upon this manual.
IV
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ACKNOWLEDGEMENTS
The U.S. FPA Project Managers were Ms. Elva Slagle and Mr. Kirk Foster.
The authors sincerely appreciate their assistance and interest in this project.
The Engineering Science Project Manager was Ms. Robin Segall and she was aided
by Ms. Gale McCorraick. A portion of this document was prepared by Richards
Engineering under subcontract to Engineering Science, Inc. The Project Manager
at Richards Engineering was Dr. John R. Richards, P.E. Ms. Kathz Butz of
Graphic Associates prepared the drawings for this manual.
Engineering Science and Richards Engineering would like to thank the 15
companies who permitted photographs to be taken of their air pollution control
systems. We sincerely appreciate the considerable support they provided in
obtaining the necessary photographs. We would also like to thank Mr. Jim Orr
of the Pennsylvanin Department of Environmental Resources and Mr. John Reggi of
the West Virginia Air Pollution Control Commission for their help with this
project.
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SLIDE 1-1
This program is designed to help air
pollution control equipment inspectors
recognize and avoid common health and
safety hazards. The slides shown in
Lecture 1 introduce the major categories
ies of hazards encountered in industrial
facilities.
SLIDE 1-2
Walking hazards are one of the major
causes of accidents involving field
inspectors. This slide illustrates a two
foot drop along an elevated catwalk.
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SLIDE 1-3
The icy surface shown in this slide is
another common walking hazard. A fall
in this area could easily result in a
serious head injury.
SLIDE 1-4
The inspection of air pollution control
equipment often involves climbing of
ladders. Proper ladder climbing prac-
tices are mandatory.
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SLIDE 1-5
Extended exposure to high noise levels
can lead to gradual hearing loss. Hear-
ing protection is often advi
SLIDE 1-6
Most metallic surfaces in air pollution
control equipment are very hot. Direct
contact can lead to a painful burn.
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SLIDE 1-7
Improper handling of flammable liquids
can result in an explosion.
SLIDE 1-8
Inhalation hazards are often present in
the vicinity of the air pollution con-
trol systems and other areas which must
be inspected.
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SLIDE 1-9
FACTORS CONTRIBUTING TO
POTENTIAL INSPECTION SAFETY
PROBLEMS
' Lack of personal safety equipment
> Lack of familiarity with plant hazardous locations: trip
hazards, overhead obstacles, equipment movement
areas, and partially confined areas
• Synergistic effects due to the accumulation of numerous
pollutants
> Lack of acclimatization to heat
A number of factors increase the inspec-
tor's risk with regard to health and
safety hazards. These factors are in-
troduced in the next two slides. These
are discussed in more detailed through-
out the program.
SLIDE 1-10
FACTORS CONTRIBUTING TO POTENTIAL
INSPECTION SAFETY PROBLEMS
(continued)
• Potential sensitivities to pollutants and materials which
are encountered
• Attempts of plant personnel to hurry Inspector
• Lack of safety considerations due to conversations with
plant personnel
• Lack of inspector training
• Lack of medical monitoring program.
The purpose of these last two slides is
to convince field inspectors that they
are not immune to health and safety
problems.
It is important that field personnel
exercise care while performing inspec-
tions of air pollution control systems.
Each inspector must be aware of and
adhere to all agency and plant safety
policies. Furthermore, the field work
should be conducted only if the inspec-
tor is in good physical condition.
All personnel involved in the inspection
of air pollution control sources should
have formal training in safety policies
and procedures before beginning the
field work. This course is intended to
supplement this formal training.
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SLIDE 2-1
This lecture concerns the numerous
physical hazards which can be found
while walking to or working around
air pollution control systems. The
list presented in the adjacent slide
presents some of the most common and
potentially dangerous conditions.
A number of slides are presented
to illustrate the importance of the
safety procedures mandated by EPA
Policy and described in the refer-
ences listed earlier.
The risk of accidents due to these conditions can be minimized by ad-
herence to basic safety procedures and by common sense. Unfortunately,
some inspectors can get distracted while conducting the inspection. This
can occur due to general unfamiliarity with the plant or due to conver-
sations with the plant personnel. Accidents are more likely when the
inspector forgets to look for the physical hazards. These problems are
avoided by conducting the inspection at A CONTROLLED PACE.
SLIDE 2-2
>
WALKING &
WORKING
Source: National Audiovisuals Center
Slippery areas are very common near
air pollution control systems. A
fall can result in serious injuries
to the head or other parts of the
body. These areas should be avoided
to the extent possible. If it is
necessary to go through slippery
areas, the proper type of shoe
should be used.
It is not always possible to see
that an area is slippery. The sur-
faces of some sludge and, wet fiber
layers often disguise the slippery
nature of the material. Even ice is
hard to identify in some cases.
The inspector should be looking for slippery areas (1) around all wet
scrubber systems, (2) while walking on any surface which could have oil or
grease deposits, or (3) while walking on any settled deposits.
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SLIDE 2-3
During the inspection of wet scrub-
bers and other control systems,
there is a natural tendency to look
around or up at the various system
components. Falls can easily occur
on the slippery areas which are
often beneath these systems.
This slide shows the area around the
main recirculation purnp of a wet
scrubber. The entire area is very
slippery. A fall here could result
in a head injury on one of the foot-
ings shown in the slide.
Most centrifugal pumps suffer some leakage due either to packing
problems or to the packing seal water. If it is not adequately drained,
the area around the pump can be very wet. This particular system also
suffered an occassional recirculation tank overflow because of foaming.
This deposited wet fibrous material on most of the walkways near the
scrubber. Although the entire system could not be shown on this slide, it
was possible to avoid this wet area without limiting the inspection.
SLIDE 2-4
This is a view of the area under an
electrostatic precipitator serving a
pulverized coal-fired boiler. It is
very common to find solids deposits
in this area because of the occas-
sional need to clean out one of the
hoppers. Small puddles of water re-
maining after a rain can make this a
treacherous walking surface. There
are numerous pipes, conduits,
valves, and beams throughout the
area and this makes any fall parti-
cularily dangerous. It should be
assumed 'chat all areas underneath
hoppers are slippery and thus they
should be approached cautiously.
Later in the lecture other potential problems which can be encountered
under hoppers will be discussed. These include hot, free flowing solids,
high concentrations of toxic gases, and hot surfaces. Obviously, hopper
areas must be approached carefully. They should not even be entered un-
less the inspection data gathered during the initial phase of the inspec-
tion clearly illustrates the need for information concerning the hoppers.
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SLIDE 2-5
This is a railcar unloading shed
which is equipped with a baghouse to
control the lime unloading opera-
tion. One of the ways to get to the
baghouse passes by the track and car
puller shown in this slide. If the
cable shown snapped while a person
was walking along this track a
severe injury would be possible.
Inspectors should avoid the area of
the car puller when the cable is
under tension.
In this case, the unloading shed can
be approached from the opposite
direction.
Rail sidings are commonly visited by inspectors since many of them
have small baghouses on the loading and unloading operations. They are
also used occassionally as vantage points for making visible emission
observations. It is best to avoid these sidings to the extent possible.
SLIDE 2-6
Another rail car unloading operation
is shown in this slide. Inspectors
should not walk between the cars
since these trains are often remote
controlled and can move without any
warning. The operator may not be
aware of the presence of people and
may not be able to see everyone in
the siding area.
As a general rule, inspectors should
allow 75 foot clearance from any
stopped engine or cars. Also,
visible emission observations should
not be made while standing on the
tracks.
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SLIDE 2-7
Source: National Audiovisuals Center
While walking around the plant area
the inspector should be conscious of
moving equipment such as forklifts
and cranes. The operators usually
are careful, however, they may not
be aware that someone is in the
area.
This problem has become more common
lately as some plants reduce or turn
off the plant lights to save energy.
These plants may conduct operations
only at night and have just a small
crew in the plant during the normal
working hours. Plant personnel
operating forklifts do not expect
anyone to be in the plant and can
not see very far ahead.
In such cases, the inspector and plant representative (if any) should
try to reach the air pollution control equipment by walking outside the
plant buildings. If this is not possible, the inspector should be careful
while walking through the plant.
SLIDE 2-8
This is the first of a series of
three slides of a venturi-rod scrub-
ber installation. The weather con-
ditions during the inspection were
less than ideal.
The vantage point of this slide is
the one that would be chosen by the
inspector to make a visible emission
observation (if it was not snowing).
There is obviously a considerable
amount of sludge surrounding this
area. This sludge is common at the
plant except during very dry periods
or when the scrubber is down.
The inspector would have to be careful to watch where he or she is
walking while choosing a site to make the visible emission observation. In
some cases, the inspector becomes preoccupied with checking for the proper
sun angle and the wind direction and forgets about the slippery surface.
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SLIDE 2-9
This is a view of part of the system
from approximately the same vantage
point as the last slide. There is a
settling basin close to the location
where a visible emission observation
would be made. This has a ground
level entry and a steep slope to
permit front end loaders to clean
out the accumulated sludge when the
basin is emptied. It would be easy
to slip into this pond.
This style of settling basin is very
common. It is the preferred basin
design in many cases because it is
easy to clean out and has good
settling properties.
The areas immediately around this basin or any settling pond should
be avoided by the inspector. Samples of the liquor should not be obtained
at this location since it is usually much safer and easier to get samples
of the pond or basin liquor from sampling points downstream of the main
pump.
SLIDE 2-10
This is a view of the same area
shown in the previous slide. It was
taken 15 seconds after the previous
slide. A large steam cloud has
almost entirely obscured the loca-
tion of the settling pond. An un-
suspecting inspector who is moving
too fast could easily get too close
to the entry to the basin under
these conditions.
It is common for steam clouds to
intermittently "mask" the walking
surfaces around air pollution con-
trol systems. The inspector should
not proceed until there is adequate
visibility.
Some inspectors make the assumption that they are familiar with the
obscured area and can therefore proceed. This can be a very bad assumption
since plant personnel may have forgotten to replace a grating, have left
some rope or other obstacles, or made other changes. An inspector usually
visits a plant only once or twice a year. Many changes can occur between
inspections.
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SLIDE 2-11
Source: National Audiovisuals Center
Up to this point every slip hazard
has been wet. There are numerous
other slippery areas caused by oil,
grease, or solids. This slide il-
lustrates a small quantity of very
slippery "marble" type deposits.
This area could be easily avoided as
long as the inspector (and the plant
personnel accompanying the inspec-
tor) were looking for slippery
areas.
Another common cause of slippery
areas is oil or grease leaking from
moving machinery.
The best way to minimize the risk from these types of deposits is to
avoid rushing during the inspection. In some cases, the inspector is
anxious to get to a malfunctioning control device. Also, some plant per-
sonnel are anxious to get the inspector "out the door" so that they can
continue with their work. It is the responsibility of the inspector to
make sure that the inspection is conducted at a controlled pace so that
this type of accident does not occur.
SLIDE 2-12
This a photograph of a small reverse
air fabric filter. The ambient
temperature during the inspection
was approximately 20°F and it had
snowed three days earlier. The
weather conditions created several
slip hazards.
Prior to starting the inspection of
this system (or any system) it is
important to survey the situation
for slip hazards and all other types
of potential problems. The inspec-
tion should then be conducted in a
manner which minimizes these poten-
tial problems. If it can not be
done safely at the present time, it
should be terminated.
In this case, only part of the inspection could be safely done. It
was possible to check the opacity of the filter discharge and the adequacy
of the solids discharge system operation. It would have been possible to
check the pressure drop safely, however, the gauge was not working. The
use of portable instruments would not have been safe at this unit on this
day. Furthermore, the inspector should not have gone up to the platform
surrounding the collector compartments. The potential problems here are
shown in the next few slides.
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SLIDE 2-13
This is a view of the ground next to
the platform access ladder. It
would be easy to slip on the ice and
hit one's head on one of the
footings shown in the slide. There
was also a lot of debris around this
area which could make any fall a
serious problem. This is one of the
reasons that the inspector should
not go up the ladder on this day.
This ice is relatively easy to spot.
In some cases, it is not quite so
obvious that the area is slippery.
SLIDE 2-14
This is the wooden platform around
the fabric filter compartment. The
mound of ice made getting traction
very difficult. In addition to a
simple fall on the platform, it is
conceivable (but not likely) that a
person could slip under the mid rail
and fall to the ground due to the
lack of a toe guard on the railing.
Due to the ice in this location it
is unadvisable to continue the in-
spection. In this case, the
portable instruments could not be
used to check the pressure drop and
the clean side deposits could not be
evaluated.
It would be impossible to see this ice from the ground. Upon reaching
the top of the access ladder the inspector should determine that the
surface is not adequate and proceed directly back down.
This is a common problem with fabric filters mounted on the roofs of
silos and other flat surfaces. These units can be 50 to 150 feet above the
ground and a fall could be very serious. It is especially difficult to re-
move an injured person (eg. broken leg, sprained ankle) from these high
locations.
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SLIDE 2-15
This is a view of a railroad siding
next to a fabric filter system. It
is apparent that there is some ice
approximately 15 feet ahead. What
may not be apparent is that the
entire area is slick. The area in
the foreground is "black ice". It
seems slipperier than the regular
ice in the background of the slide.
The "black ice" is simply frozen
water having a very high suspended
solids content.
While looking up at the rail car loading shed baghouse it would be
easy to miss this very slippery area. It must be relatively cold for this
ice to form. The day this photograph was taken the temperature was 8°F.
SLIDE 2-16
This is a venturi rod scrubber
mounted on a horizontal roof. A
small puddle of water on one side of
the unit has frozen. There were
several sharp corners which might be
hit during a fall.
This is the most direct path from
the access ladder to the location of
*•"-- differential pressure gauges,
the
to
However, there was another way uu
reach the gauges without having to
worry about the ice.
During cold weather it should be assumed that almost all elevated
horizontal surfaces will have some frozen puddles or other slippery areas.
Since some of these surfaces do not have guard rails, it is particularly
important to avoid the slippery ones.
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SLIDE 2-17
This is a plank leading from an
access ladder over to the area of a
flooded disc scrubber. The roof has
some ice and there is no guard rail.
It is important to be especially
careful of slip hazards on elevated
surfaces. Falls from these surfaces
can be fatal. Many of the elevated
surfaces were not intended for walk-
ing, therefore guard rails are often
missing. Some of these surfaces are
also sloped.
There is no guarantee that the temporary plank or other walking sur-
face is free from ice or water. In the case shown above, the board was
moderately slippery due to water which had dripped off an adjacent roof and
refrozen over night. Deposits of fugitive materials on the plank also made
the walkway slippery.
SLIDE 2-18
This is a temporary walkway over an
excavated area. It is probably safe
as long as (1) it is in regular use
by plant personnel, (2) the wood
appears to be in good condition, and
(3) the ends will not slip. Never-
theless, it is a good practice to
let the plant representative along
on the inspection go first. Also,
no more than one person at a time
should cross this temporary bridge.
Occassionally, these might be found
in remote areas of the plant. It is
possible that the wooden planks
have rotten or that the ends are no
longer secured. The integrity of the
walkways should be questioned and it
should be avoided if possible.
Under no circumstances should an inspector cross between two platforms
or buildings (or any other crevice) by means of a ladder or single plank.
Ladders are not intended for this service and are sometimes not secured
properly. The inspector should refuse to cross any potentially unsafe
walkway (such as a ladder, a single plank, or a weakened bridge) even if
the distance is short or plant personnel insist.
Source: National Audiovisuals Center
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SLIDE 2-19
Before going up to any elevated
platform around an the air pollution
control system, the integrity of the
platform should be quickly checked
from the ground. This is a view of
the wooden walkway on the baghouse
shown earlier. The condition of the
boards and the support angle irons
should be checked before climbing
the ladder up to the platform. Once
you are on the platform, it is very
difficult to confirm that it is
structurally secure.
Some of the common problems include
rotting of the wooden boards, cor-
rosion of metal walkways, and
failure of the supports.
This is the walkway around a new
pulse jet baghouse. Both the walk-
way and the supports appear to be
very secure.
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SLIDE 2-21
Before moving to an elevated plat-
form the inspector should also con-
sider whether there is a risk of
being trapped on the platform while
a rising cloud of toxic gas or high
temperature steam passes. If so,
the inspection should only be con-
ducted when the source of the gas or
steam is not on. In some cases, the
inspector may be able to use a res-
pirator and/or some protective
clothing if the process equipment
must be operating during the
inspection.
There are some cases where an inspection can not be done safely with
or without protective equipment and clothing. In such cases, the inspector
must be content with simply evaluating emissions from a distance or the
evaluation of instrumentation located in safe areas.
Inspectors should not underestimate the potential problems resulting
from rising steam clouds and/or toxic clouds of pollutants. They can form
suddenly due to a process upset and it is difficult to get off a platform
when both visibility and breathing is impaired. Several inspectors have
been very seriously hurt due to this problem.
SLIDE 2-22
This is a typical roof at a manu-
facturing facility. It would be
necessary to be on this roof to read
the visible emissions coming from
the various small vents. A quick
shift in the wind direction would
result in the fumigation of the
inspector. The bluish white aerosol
could contain some very toxic and
irritating materials. The inspector
must know ahead of time what pos-
sible pollutants are in the plume
and carry with him the appropriate
type of respirator for this
material.
The position used for the visible emission observation should be
normal to the wind direction. This places the inspector in the direct line
of travel of plumes from other process vents or discharge points. Before
selecting a location for the observation, the locations of all discharge
points (both continuous and intermittant) should be determined.
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SLIDE 2-23
ilegardless of the apparent strength
of an elevated platform, large num-
bers of people should not be on it
platform at one spot.
SLIDE 2-24
There are some elevated surfaces
which may not be able to withstand
any additional load. An inspector
who walks across a roof as shown in
this slide may fall through. It is
very important that inspectors only
walk in areas designated as safe by
the plant personnel. This is one of
the reasons that it is essential
that plant personnel accompany the
inspector. It is prudent for the
inspector to walk behind the plant
personnel.
Plants may replace sections of worn corrogated metallic roofing with
FRP corrogated roofing. The latter does not usually have the load bearing
capability of the metallic roofing, therefore, an inspector walking across
a supposedly secure roof could fall through. While the FRP material should
be easy to identify, in the many cases a thin layer of fugitive material
(as shown in the above slide) can easily disguise it. This is another
reason that the plant representative should accompany the inspector.
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SLIDE 2-25
One sign of potential roof loading
problems is the presence of large
deposits of solids or snow. This
can render an otherwise secure roof
into a major hazard, especially in
the immediate vicinity of the solids
deposits.
The deposits shown in this slide
were due to the clean out of a
plugged hopper on a baghouse which
is up and to the right of the view
of the slide. The area near these
deposits should be avoided if at all
possible.
SLIDE 2-26
Not all guard rails on elevated
platforms and walkways can actually
withstand the 200 pound force for
which they were designed. Leaning
against weak railing could result in
a serious accident. Inspectors
should check the integrity of these
railings, if possible. Under no
circumstances should the inspector
risk a fall, however, in order to
check the adequacy of the guard
rail.
This railing was next to a venturi
si rubber. An inspector may have
been tempted to lean against this
j ailing in order to see the main
pump and the static pressure gauges.
This railing was very weak.
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SLIDE 2-27
This photograph shows an inspector
ducking under a pipe which has been
welded to guard rails along a walk-
way between two baghouses. This was
necessary to prevent the guard rails
from falling. Despite the "fix" the
inspector should place very little
faith in the security of these guard
rails.
The bar across the walkway provides
an interesting hazard on its own.
The inspector who is preoccupied in
conversation with plant personnel or
in looking at the baghouse exhaust
could easily flip over the bar. The
location of the bar is below the
center of gravity of most people.
Looming directly ahead of the falling inspector is a three foot drop
in the catwalk. The fall could result in (1) a fall over the catwalk, (2)
serious eye injuries on the exposed ends of the grating, and (3) serious
head injuries. Obviously, it is important to watch where you are going and
to conduct the inspection at a controlled pace.
SLIDE 2-28
This is a view of the three foot
drop off in the catwalk. The bar
discussed in the previous slide is
directly above the field of view of
this slide.
This is not an adequate walkway.
This is the type of situation which
should be brought to the attention
of your supervisor before conducting
the inspection of the baghouse at
the far end of this catwalk.
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SLIDE 2-29
At the other end of the walkway
shown earlier, it is necessary to
step off the catwalk to a support
beam, over some electrical conduits,
to the next platform. This is shown
in this slide and the one directly
below.
Failure to negotiate this obstacle
course could result in a fall of 30
feet.
SLIDE 2-30
These slides were taken simply to
show the types of catwalks which may
be encountered, especially in some
of the older facilities. Inspectors
should not attempt to use these.
This is not adequate and safe access
to the control equipment.
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SLIDE 2-31
There is a missing section of grate
in this walkway. The unsuspecting
inspector could fall approximately
two feet to the roof of a baghouse
directly below the catwalk. For
those who have been keeping score,
this is the fourth major hazard in
the 40 foot run of this particular
walkway.
SLIDE 2-32
Missing gratings or gaps in gratings
can occur anywhere in a plant. In
some cases, the gratings were ori-
ginally intended to protect people
from entrapment in rotating equip-
ment such as the auger shown here.
This missing sections are easy to
miss if the plant is only dimly lit
or if the inspector is trying to
avoid obstacles which are overhead
at the same time. Plant personnel
often rush through these areas
without giving the hazards much
thought because they have become
accustomed to them. The inspector
should not feel obligated to "keep
up" and possibly incur a serious
accident.
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SLIDE 2-33
This a picture of the floor around a
packed bed wet scrubber. The entire
system is in a very dimly lit build-
ing. While walking between the bar-
rels and other stacked material it
would be easy to miss the raised
section of the floor shown in this
slide. The severity of the accident
would depend on what was hit on the
way down.
Whenever entering an internal area
from the outside, it is prudent to
wait for the eyes to adjust to the
low light conditions.
SLIDE 2-34
This is an example of what may be
lurking in those dimly lit areas.
Source: National Audiovisuals Center
23
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SLIDE 2-35
This is the pathway to a large bag-
house. All of the metal is rust}
and most of it is sharp.
SLIDE 2-36
Around many small baghouses, the
solids discharge valve is mounted at
a low spot close to the access lad-
der for the unit. This is shown in
the adjacent slide. The rotary
valve shown here is just high enough
that it may not be seen while
approaching the ladder.
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SLIDE 2-37
The valve stem shown in this slide
sticks out onto a catwalk near the
top of a venturi scrubber. It is
hard to see due to the lack of light
in this part of the building.
SLIDE 2-38
A tie down stack for an ambient
monitoring trailer is shown next to
the access ladder. It is necessary
to go up the ladder to check on the
Hi-Vol collector. While coming
down, it is easy to forget the stake
and chain.
Whenever getting off any ladder at
the top or the bottom, it is useful
to pause momentarily to check for
obstacles ahead.
25
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SLIDE 2-39
This is the same monitoring trailer
shown in the last slide. The recess
shown in the slide is a favorite
habitat of wasps and bees. Other
common nesting areas include the
sheltered areas directly below roofs
of baghouses and sheltered areas be-
low some types of outdoor control
cabinets. If you are hypersensitive
to wasps and bees, you should ask
the plant personnel where at the
plant they are usually found so that
you will not inadvertently disturb
the insects.
SLIDE 2-40
While walking around an air pollu-
tion control device, it is easy to
forget about rotating equipment in
the general area. This slide shows
a partially covered fan sheave and
drive belt. This was along a very
narrow path to a venturi-rod scrub-
ber. It is conceivable (but not
easy) for loose clothing to get
caught between the rapidly moving
belt and sheave. Occassionally, the
entire belt guard will be missing.
One way to minimize the risk of en-
trapment in rotating equipment is to
avoid wearing loose fitting clothes.
Ties should never be worn.
The area immediately around the rotating equipment should be avoided
to the extent possible. If there is only one path to the control system
and there is a realistic risk of entrapment even when the inspector is
exercising caution, then the inspection should not be conducted.
26
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SLIDE 2-41
This is a winch beside a narrow path
to the same system discussed in the
last slide. It is 4 feet above the
surface and the cable cuts over the
path that must be taken by the
inspector. The operation of the
winch is controlled by plant person-
nel who cannot see the scrubber from
their work station. Resting one's
hand on the winch or simply being
too close when it starts up could
result in a painful injury.
It should be assumed that equipment
which is designed to move could move
without any warning.
SLIDE 2-42
It is often difficult to find an
acceptable location for making the
visible emission observation for
tall stacks such as those found at
large utilities. An inspector may
be tempted to climb the coal pile
for this purpose. These usually
have underground coal conveying
equipment which makes standing on a
coal pile very dangerous.
27
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SLIDE 2-43
While walking through the plant or
under control equipment, inspectors
must be aware of overhead beams and
other obstacles. Without a hard hat
it is possible to sustain a serious
head injury on these overhead ob-
stacles. Hard hats should be worn
during all plant inspections unless
there is a compeling safety reason
why they should not be worn at a
specific plant. Inspectors should
wear hard hats even at plants which
do not specifically require them to
be worn.
SLIDE 2-44
Many air pollution control systems
can be reached only by climbing. It
is also necessary to climb to almost
all sampling platforms. The next
portion of the lecture concerns the
proper procedures for climbing lad-
ders, recognizing safe and unsafe
ladders, and potential ladder
related accidents.
Source: National Audiovisuals Center
28
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SLIDE 2-45
This illustrates a common problem
with ladders leading to air pollu-
tion control systems. Often the
first person up the ladder (normally
the plant representative) deposits a
layer of mud and sludge on the foot
rungs. The mud and sludge comes
from the general conditions shown in
previous slides such as 2-3 and 2-4.
These deposits can make the ladder
slippery. It is particularly im-
portant to climb the ladder care-
fully under such conditions. If
conditions are too extreme, the
ladder should not be used.
SLIDE 2-46
This illustrates the WRONG way to
climb a ladder. The inspector has
placed his hands on the side rails
of the ladder to avoid the mud which
is on the foot rungs. He may not
be able to support himself if his
foot slips on one of the slippery
foot rungs. Only the foot rungs
should be grabbed while climbing,
never the side rails. In many cases
it is necessary to have gloves for
climbing the ladders.
29
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SLIDE 2-47
This is the proper way to climb the
ladder. The inspector is holding
onto the the foot rungs.
SLIDE 2-48
This illustrates another common
error made in climbing ladders. The
inspector shown in this slide is
attempting to carry the portable
instruments in one of his hands (he
is also holding on to the side
rails). Both hands must be free for
holding on to the foot rungs.
If it is necessary to get the por-
table instruments to an elevated
platform or control device, a rope,
side pouch, or back pack can be
used. It is important that the
pouch and/or back pack do not inter-
fere with climbing by getting lodged
in the ladder cage or other surroun-
ding objects.
30
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SLIDE 2-49
This slide illustrates climbing with
the side pouch. Note that both
hands are now free for climbing.
The dangling dial type thermometer
near the back of the pouch could get
caught of a portion of the cage (not
shown). Instruments which are as
long as the dial type thermometer
should not be carried in the side
pouch.
A bucket with a rope can be used to transport large instruments,
cables, and any other bulky items. Obviously it is important that nothing
falls from the bucket. The rope and bucket should not be used near power
lines or when the wind speed is high.
SLIDE 2-50
The last two slides have shown an
inspector with gloves climbing the
ladder. This slide shows a common
type of slip resistant foot rung.
It is very helpful to have gloves
when climbing this type of ladder.
31
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SLIDE 2-51
This slide shows the same ladder as
the previous slide. The inspector
is attempting to climb the ladder
without gloves. To avoid pain, he
is hooking his wrist around the back
of the foot rung. He obviously has
only a very poor grip of the foot
rung and he could easily fall. This
should never be done.
SLIDE 2-52
This is a view down a 30 foot lad-
der from a baghouse. It is readily
apparent that the foot rungs are
both rusty and have some very sharp
edges. Gloves and caution are a
necessity when climbing a ladder of
this type. It may be advisable to
find another means of access or to
delay inspection of the particular
unit until there is a better ladder
available.
32
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SLIDE 2-53
In evaluating whether or not a lad-
der is safe, there are a number of
different factors which must be con-
sidered. As shown in this slide,
the fixed ladder with cage must ex-
tend at least 3.5 feet above the
surface of the roof or elevated cat-
walk.
Source: National Audiovisuals Center
SLIDE 2-54
The ladder must be at least 18 in-
ches wide. Generally the width of
the rung meets the criteria shown
here, however, the cage can be
damaged. This can restrict access
at the point that the cage is bent
inward and can make the ladder very
dangerous if the inspector is climb-
ing with a side pouch or back pack.
Source: National Audiovisuals Center
33
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SLIDE 2-55
There should be 8 inches clearance
between the foot rungs and any back
wall. This is necessary to ensure
that the foot rests securely and
completely on the foot rung. The
person shown in this slide should
have been climbing by placing the
back of the heel against the foot
rung.
While the large majority of ladders
on control systems initially have
the necessary foot clearance, it is
fairly common to have electrical
conduits or obstacles at one part of
the ladder. This can result in a
misstep and fall.
Occassionally, there may be a support beam passing across the back of
the ladder closer than 8 inches. While climbing the ladder, it is useful
to watch out for these beams, conduits or other potential problems.
SLIDE 2-56
The foot rungs should be evenly
spaced to prevent missteps and falls
from the ladder. This slide shows
the poor mating of a small extension
section to the bottom of a large
ladder going to a small baghouse.
The gap between the two ladders is
different than the distance between
the foot rungs of either ladder. An
accident is most likely while coming
DOWN from the baghouse since it is
easy to forget that the ladder has
been "pieced" and you cannot see
it coming.
34
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SLIDE 2-57
Ladders are supposed have some type
of secure guard to prevent someone
from inadvertently walking into the
open area at the top of the ladder.
This slide illustrates a very good
type of guard which will close auto-
matically when leaving the ladder.
SLIDE 2-58
This slide shows the top portion of
a caged ladder which does not have
any restraint at the point of entry.
The chain which was formerly across
the entrance of the ladder has been
removed.
Accidents can occur at spots like
this when the inspector becomes
preoccupied in conversation with
plant personnel or is too busy
looking at components of the control
system. This is another reason that
the inspection must be conducted at
a controlled pace.
35
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SLIDE 2-59
This slides illustrates an uncaged
ladder with a permanent angle iron
across the entry point to the ladder
top. To climb down from the fabric
filter shown in this slide, it is
necessary to duck under the bar and
then attempt to keep your feet on
one of the foot rungs. This is not
an adequate access ladder. The
angle iron should be replaced with
one of the types of restraints shown
in the last two slides.
SLIDE 2-60
This is the top of a AO foot ladder
leading to a set of small baghouses.
Approximately 6 inches above the top
of the ladder is a large lamp. A
tired or unaware inspector could hit
either the lamp itself or the its
sharp reflector. The result could
be a head injury, a fall, or both.
36
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SLIDE 2-61
t
This is a ladder leading from an
internal catwalk to a roof where
there are several baghouses. There
is very little clearance between the
sloping roof and the edge of the
siding directly above the ladder.
To complicate matters further, the
solids on the sloping roof are very
slippery. While trying to concen-
trate on one problem, an inspector
could easily forget about the other.
SLIDE 2-62
Sometimes it is not the ladder that
is dangerous, but the general con-
ditions near the ladder. This slide
shows a ladder leading up to a wet
scrubber on a cupola. During the
short periods when slag is being
skimmed, the area surrounding the
ladder is enveloped with a dramatic
display of sparklers.
37
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SLIDE 2-63
This is a slide of another access
ladder leading to a cupola scrubber.
The plant personnel are in the pro-
cess of "dropping bottom". While
plant personnel are usually quite
careful in this situation, they may
be unaware that an inspector is in
the area. The burst of fire that
results from "dropping bottom"
develops in a fraction of a second
once the bottom support is withdrawn
from the cupola. A person just
coming down the ladder from the
scrubber would be very seriously
burned. It is necessary to be con-
stantly aware of the operations
under way at the plant during the
inspection.
SLIDE 2-64
This is an entry way from a roof to
a ladder leading down to the plant
floor. Very high humidity results
in a steaming effect as the cold
ambient air enters the warm, humid
air. A cloud of steam is apparent
on the left portion of the entry
way. Upon entering this area, any
inspector wearing glasses will not
be able to see. The steam can be so
heavy at times that even those
without glasses can not see more
than a foot ahead. Several feet
into the enclosure is an opening for
the ladder. There is no restraint
or other protective device to pre-
vent the temporarily blinded inspec-
tor from taking a 30 foot plunge
through the opening down to the
operating floor.
Any steam filled area deserves special precautions. The inspector must
slow down until it is possible to see all obstacles, openings in the floor,
and other hazards. Extremely low visibility caused by steam is one of the
most common conditions encountered in inspection of air pollution control
equipment.
38
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SLIDE 2-65
Portable ladders can present some
special problems for the inspector.
Before using these ladders, several
basic safety checks are needed.
Source: National Audiovisuals Center
SLIDE 2-66
Makeshift ladders such as the one
shown in this slide should not be
used under any circumstances. If it
has been necessary to "fix" one of
the rungs, it is possible that some
of the others have also weakened.
All of the foot rungs should be in-
spected before use of the ladder.
If any of these appear to rotted or
the rungs are separating from the
side rails, the ladder should not be
used.
Source: National Audiovisuals Center
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SLIDE 2-67
One of the basic requirements of a
portable ladder is that it must be
secure at the bottom. It is often
difficult to find a location near
air pollution control equipment
where there is no sludge or mud.
This slide shows a ladder sitting in
a slippery layer of sludge next to a
venturi scrubber. There is a possi-
bility that anyone using this ladder
would fall.
In addition to locating a dry spot for the ladder, it is necessary to
have the right type of slip resistant protector on the bottom of the lad-
der. Two of the most common slip protectors are spurs and pads.
SLIDE 2-68
This is the same ladder shown in the
previous slide. Another common pro-
blem with portable ladders involves
resting them against a support which
is weak. Close examination of the
slide illustrates that the small
angle iron which is supporting this
ladder has been cut approximately
80% of the way through. The load
created as the inspector climbs the
ladder will be enough to cause the
angle iron to break.
40
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SLIDE 2-69
When using any portable ladder, it
should be sloped so that the length
from the wall is one fourth the lad-
der height. This is illustrated in
this slide.
Source: National Audiovisuals Center
SLIDE 2-70
The portable ladder should extend
three feet above the roof. This is
illustrated in the adjacent slide.
Source: National Audiovisuals Center
41
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SLIDE 2-71
The ladder should never go to or
near the vicinity of power lines.
If this is the only way to reach the
air pollution control equipment,
then the inspection should not be
conducted at the present time.
Source: National Audiovisuals Center
SLIDE 2-72
When climbing any fixed or portable
ladder, only one person should be on
the ladder at a time. The first
person going up the ladder could
drop some tools or equipment on the
person climbing directly below. The
first person could also fall and
thereby injure the second. While it
takes more time to wait for each
person to reach the top of the lad-
der, this is the only safe way to
climb.
Source: National Audiovisuals Center
42
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SLIDE 2-73
The basic personal protective items
necessary for walking and climbing
are shown in this slide. These
should be worn by inspectors during
all inspections unless there is a
compeling safety reason why these
should not be used at a specific
plant.
SLIDE 2-74
Safety shoes have several main func-
tions. They protect against falling
objects which could injure the toes.
The types of activities where this
type of accident is likely are not
those performed by most field in-
spectors. The most important func-
tion of safety shoes, for inspec-
tors, is the slip resistant soles.
This minimizes the risk of falls on
all slippery areas around the equip-
ment and on the various types of
elevated surfaces commonly encoun-
tered by inspectors.
The purpose of this slide is to illustrate that these shoes will wear
out and become less useful for preventing falls. They should be replaced
when they reach this stage.
The type of safety shoe must be appropriate for the type of chemicals
and conditions which will be encountered. The primary considerations are
(1) the extent to which chemicals could penetrate the sole of the shoe and
the skin and (2) the potential consequences of static build-up. If there
is the possibility for static electrical detonation of flammable vapors it
may be necessary to use a shoe designed to dissipate the static.
43
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SLIDE 2-75
Hard hats should be cleaned and
inspected at the least on a monthly
basis. The suspension should be
checked to ensure that it still
meets the originial specification.
If there are any cracks or other
problems with the hat, it should be
discarded and a new one obtained.
44
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SLIDE 3-1
HAZARDS TO VISION
The eye is one of the most vulnerable
parts of the body to industrial ha-
zards. This is because it does not
heal as quickly or as well as other
organs. The cornea, lens, and humors
have very few blood vessels (so that
they are clear) which results in slow-
er healing. The nerves of the retina
cannot regenerate, so damage to these
is permanent.
3-2
EYE INJURIES
MINOR
Presence of foreign body
Abrasion from rubbing
Irritation from fumes
Orbital margin bruise
MAJOR
Perforation of eye by particles
Thermal Bums
Chemical bums from fumes or splashes
Disruption by Impact
Industrial eye injuries can range
from temporary to permanent. Exam-
ples of some common major and minor
eye Injuries are shown in this slide.
The major injuries often result in
partial or permanent blindness. It
is probably easy for every inspector
to imagine plant situations that he
or she encounters on a regular basis
that could result in injuries of each
of these types.
45
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SLIDE 3-3
This slide shows a fairly common
plant situation; this baghouse ex-
haust vent is directed down at the
platform around the baghouse. Under
normal conditions this is not a prob-
lem, however, in the case of a bag
failure, etc. particulate could be
flung at the inspector at the exhaust
gas velocity of 3,000 fpra.
SLIDE 3-4
Grinding operations such as the one
shown here or those found at foundries
and in other metal fabrication indus-
tries are a common source of flying
particles. Particles that get in the
eye can easily scratch the eyeball,
and more seriously, those traveling
very fast can perforate the eyeball
and cause internal damage, sometimes
without even being felt.
Source: National Audiovisuals Center
46
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SLIDE 3-5
This is a photograph of a valve on the
discharge line of a wet scrubber pump.
The liquor is under approximately 90
psi and the pH is quite high. If care
is not taken in sampling the liquor,
it can easily splash into unprotected
eyes. Thus, the valve must be opened
gradually, the receiving container
must not be prone to splashing, and
the inspector should be wearing splasl
goggles.
SLIDE 3-6
The fumes or vapors of some chemicals
can irritate or actually burn the
eyes. Chemical splash goggles (which
will be shown later) should always be
worn around open vats and tanks of
potentially harmful chemicals such as
those shown in this slide.
Source: National Audiovisuals Center
47
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SLIDE 3-7
This is a view inside a traveling
grate of a municipal incinerator.
Occassionally an aerosol can explodes
as the material charged to the in-
cinerator heats up. The metal frag-
ments from the can pose a hazard to
anyone looking directly into the
hatch, thus, it is wise to look into
these hatches with caution. The eyes
should never be in the possible direct
line of flight of exiting fragments
and eye protection should always be
worn.
In the case where the material inside
a hatch is very hot and bright, a ra-
diation shield may also be necessary
to prevent thermal or other radiation
damage to the eye.
SLIDE 3-8
Although not likely in the case shown,
sparking can possibly cause eye inju-
ry in either of two ways: (1) burns
from sparks reaching the eye or (2)
damage from glare or U.V. radiation.
Source: National Audiovisuals Center
48
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CATEGORIES OF EYE HAZARDS
• Physical
• Chemical
• Thermal Radiation
• Other Radiation
SLIDE 3-9
Eye hazards, Including those just
shown, can be grouped into four cate-
gories. Physical hazards include
blows such as from walking into low
hanging equipment or beams, lacera-
tions from sharp edges moving past
the eye, and the introduction of for-
eign bodies flying particles.
Chemical hazards include splashes
from opening valves or containers un-
der pressure or being near open pro-
cess vats and tanks or irritating or
burning fumes and vapors such as sty-
rene or butanol.
Thermal eye hazards include the di-
rect viewing of high temperature
operations. Fortunately, excessive
heat usually causes the eye to close,
however, this results in burns to the
eyelid.
Other radiation hazards include U.V. light from welding and cutting op-
erations, intense visible light from lasers, infrared, and microwaves.
SLIDE 3-10
This- slide shows three types of eye
protection of general use to the air
pollution control inspector. They
are (from top to bottom) chemical
splash goggles, safety glasses with
side shields (to protect against fly-
ing objects), and visitor glasses.
Most industrial facilities require
eye protection and inspectors should
be sure that theirs satisfies plant
requirements. It is suggested that
inspectors use eye protection even if
not specifically required. At the
very least, it will prevent the intro-
duction of chemicals and foreign bod-
ies into the eye by careless rubbing.
49
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SLIDE 3-11
Unlike this example, visitors specs
or glasses should not have many
scratches. If they do, a new pair
should be used and the others dis-
carded. When doing much field work,
it is preferable to have prescription
or nonprescription safety glasses with
side shields. These are less prone
to scratching and all better peri-
pheral vision.
Splash goggles should be worn whenev-
er there is the chance of splashing
chemicals or irritating fumes. Im-
pact goggles can as a substitute for
safety glasses. Radiation shields
must be used when there is danger of
thermal or other radiation.
In the event that chemicals do get introduced into the eye, immediate
treatment is essential. The eye should be flushed with as much water as pos-
sible using an eyewash station, if convenient, or any other source of clean
water. If the individual is wearing contact lenses, they must be removed
first.
ON INDUSTRIAL JOBS . . .
DON'T
WEAR CONTACT LENSES
SLIDE 3-12
This statement is from a National
Safety Council slide series on eye
safety. We also strongly recommend
not wearing contact lenses while at
an industrial plant. Many chemical
plants, in fact, do not allow employ-
ees or visitors to wear contacts in
the production areas.
There is an OSHA standard [1910.134
(e) (5) (ii)] which strictly forbids
the wearing of contact lenses in con-
taminated atmospheres with a respi-
rator.
Hard contacts can increase the damage done to the eye by a foreign body
which gets trapped behind it. Soft contact lenses, particularly the gas
permeable ones, may make the eye more susceptible to chemical damage. Some
chemicals such as acetone may also cause soft contacts to opacify.
However, to this date the National Society for the Prevention of blind-
ness has no contact-caused injuries on record as long as goggles appropriate
for the situation are worn. They have thus just issued a position statement
on the wearing of contact lenses in the industrial environment which cautions,
but does not preclude the use of contact lenses. This statement is quoted in
full on the following page.
50
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"Contact lenses may be worn in many occupations. Contact lenses provide
an adequate means of visual rehabilitation for employees who have had a cat-
aract removed from one or both eyes; who are highly near-sighted, or who have
irregular astigmatism from corneal scars or keratoconus. However, when the
work environment entails exposure to chemical fumes, vapor, or splashes, in-
tense heat, molten metals, or highly particulate atmosphere, contact lens use
should be restricted. Certain federal or state regulations may also limit
their use.*
Contact lenses, of themselves, do not provide eye protection in the in-
dustrial sense. For occupational use, contact lenses should be worn only in
conjunction with appropriate industrial eye protection.**
The employer should ensure the identification of the contact lense wearer
for appropriate emergency care and for protection in work areas hazardous to
the eyes."
*Wearing of contact lenses in contaminated environments with a respirator
shall not be allowed. Federal Register, Volume 36, Number 105, Part II
#1910, 134 (e)(5)(ii).
*To be of industrial quality, safety eyewear devices must meet or exceed all
the requirements of the "American National Standard Practice for Occupation-
al and Educational Eye and Face Protection, Z87.1, 1979", or later revisions
thereof, as published by the American National Standards Institute, Inc.
51
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SLIDE 3-13
HAZARDS TO HEARING
There are two types of noise expo-
sure: chronic and acute. Field in-
spectors are rarely subjected to the
chronic exposures.
However, the short, acute exposures
do add up and there is always the
possibility of a temporary hearing
loss even after a short term expo-
sure. Consequently, the agency in-
spector must be aware of potential
noise sources, the consequences of
noise exposure, and the methods of
hearing protection.
SLIDE 3-14
SEMICIRCULAR
CANALS
EIOHTH NERVE
OVAL WINDOW
External Ear
Middle
Ear
An intense, sudden noise (such as an
explosion) can severly damage the
middle and inner ear and can result
in hearing loss. But the type of
hearing loss associated with indus-
try is from much lower noise levels
over a prolonged period. This type
of hearing loss results because the
hair cells lining the cochlea are
gradually destroyed by overstimula-
tion. These hair cells transform
the vibration in the liquid of the
ear into nerve impulses. Once des-
troyed, they do not regenerate.
The early stages of this type of hearing loss result in an increase in
the hearing threshold only at the higher audible frequencies so it is often
not noticed. At first, the individual does not realize that he or she is
progressively losing hearing ability. Some temporary hearing loss or
ringing (ITS, Temporary Threshold Shift) does result in permanent hearing
damage.
52
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SLIDE 3-15
This slide shows an example of a
source of impact noise, one of the
types of noise that can cause ear
damage. These magnetic impulse gra-
vity impact (MIGI) rappers on the
ESP roof are commonly encountered by
agency inspectors.
This is a fan on a baghouse of a
asphalt plant kiln. Areas around
the large fans of control systems
tend to be noisy.
53
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SLIDE 3-17
This is a ball mill at a plant which
grinds clinker. THe noise level in
the area surrounding the ball mill
was high enough that one had to
shout to communicate; this is always
a good indication that it is
appropriate to wear ear protection.
SLIDE 3-18
MAJOR FACTORS WHICH
CHARACTERIZE NOISE EXPOSURE
• Overall Noise Level
• Composition of Noise
• Duration and Distribution of Exposure During the Work
Day
• Total Time of Exposure During Worklife
This slide lists the four factors
which characterize noise exposure
and which effect hearing loss. Over
the same time period, the higher the
noise level in dB, the greater the
exposure. Composition of the noise
also has an effect, single frequency
noise is more damaging than broad-
band noise. The exposure is
cumulative so that the total time
over a lifetime is important.
However, it is not strictly additive
and consequently duration and
distribution must be considered.
-------
SLIDE 3-19
MAXIMUM
EXPOSURE
PltESSURE PER DAT
M/m' <«A
INDICATORS
OF LEVEL
CHIPPER (US Ml
no
"""""•
CUANEI.
**»•<»» WHIWM
110 —
00
•0 —
M
70 —
10
BO —
1C
so —
H
10 —
.
to
15 MIN
50 MIN
I HOUR
2 t HOURS
• HOURS
VWCC COMMUNICATION IMPOS
VOICC COMMUNICATION DIFFICULT
SHOUT AT 09 FOOT
NORMAL VOICE AT. 0.8 FOOT
NORMAL VOICE AT 1,5 FEET
00001
oooooz
This scale was constructed to give
an idea of how the levels of some
familiar noise sources related to
the OSHA specified maximum ex-
posures. At the present time, 90
dBA* is the maximum noise level to
which most worker can be exposed
with a reasonable expectation of no
hearing damage. The information in
the column on the right can be used
to roughly estimated noise levels.
As a rule of thumb, ear protection
should always be used when normal
speech can not be understood at a
distance of 2 to 3 feet. (*The dBA
noise level scale is weighted for
frequencies in the hearing range.)
SLIDE 3-20
There are a number of options avail-
able in choosing ear protection.
Pictured here are premolded ear
plugs, moldable ear plugs, canal
caps, and ear muffs. Not pictured
are the less commonly used custom
molded ear plugs. Each have advant-
ages and disadvantages with repect
to comfort, and convenience in var-
ious situations. For example, ear
plugs are easy to carry but incon-
venient to put in quickly.
Ear muffs and canal caps are very easy to put on and take off, but
they cannot be stored in a pocket and are much less comfortable than ear
plugs to wear for extended periods.
The inspector should always carry his or her own ear protection and
should wear it as prescribed by the plant. Continuous wear is recommended
in a moderately noisy plant; after a short period of acclimation ear
protection actually aids communication. In addition, it is not good to be
removing and reinserting ear plugs with soiled hands as one moves about the
plant.
55
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SLIDE 3-21
Ear
Protector
Bangs of
Attenuation
Cotton
Ear Plug
Ear Muff
Muff & Plug
5 to 2MB
15 to 35dB
15to45dB
28to48dB
Different types of ear protection
differ in the amount of attenuation
or reduction of noise level that
they provide. This slide shows the
reanges of attenuation for four
forms of ear protection. Attenua-
tion is given as a range because it
differs at different frequencies.
The cotton is not a recommended form
protection and is shown for compari-
son purposes. The attenuation of
properly fitted ear plugs and ear
muffs is nearly equivalent. A com-
bination of the two can provide
additional protection. Probably the
most important factors for the in-
spector to consider when selecting a
type of ear protection are (1) noise
levels, (2) proper fit (3) reason-
able comfort, and (4) convenience.
If ear protection is comfortable and
convenient, it will usually be used.
56
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SLIDE 4-1
Electrical hazards, explosions and
burns are discussed in this lecture.
Since gas temperatures between 200
and 1800 °F are common in air pollu-
tion control equipment, there are a
number of ways for a burn to occur
in the vicinity of the collector.
Burns can also occur due to steam
from process equipment.
Explosions can occur when there are
(1) deposits of solids or (2) flam-
mable liquids being handled. Both
of these situations occur during
inspections.
Electrical shocks can occur due to improperly grounded equipment, im-
properly grounded probes, exposed wiring, high voltage tracks, and opening
of electrical cabinets.
SLIDE 4-2
This slide shows flames engulfing an
access ladder to a cupola wet scrub-
ber system. This occurs when the
plant is "dropping bottom". The in-
spector should not go near the
scrubber system when this is to
occur.
Plant personnel are usually quite
careful about advising inspectors
about this operation. The problem
could occur when the cupola operator
is unaware of the presence of the
inspector. The inspector must be
aware of process operations and must
not assume that the operators will
realize that he or she is present.
57
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SLIDE 4-3
This is a view of a wet scrubber
system on another cupola. The gas
leaving the top of the cupola is at
temperatures varying from 1800 to
2200 °F. There is a small quench
chamber adjacent to the cupola to
reduce the gas temperature to the
300 to 400 °F. The gas then travels
down the inclined duct to a venturi
rod scrubber. The next slide shows
a close-up view of the gas duct at
the inlet of the scrubber.
SLIDE 4-4
The gas duct shown in the previous
slide is at the very top of this
slide. The main liquor inlet is on
the left side of the scrubber inlet
(near the center of the slide). The
discolored area just below the main
liquor inlet shows that the gas
temperature at this point can be
quite high. Leaning against this
portion of the scrubber could result
in a painful burn. This part of the
unit is within easy reach of anyone
walking around the unit.
It is very common to find uninsulated ducts near air pollution control
equipment that are between 200 and 800 °F . Touching the duct walls can
occur as the inspector is (1) trying to move around the various obstacles
around the collector or (2) attempting to use a measurement port on the
duct wall. To minimize the risk of burns, it is necessary to be constantly
aware of which ducts are at elevated temperature.
58
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SLIDE 4-5
A row of 4 inch diameter sampling
ports are shown here. Most people
are careful initially and use gloves
to remove the plugs. When prepar-
ing to leave, they often forget that
the plugs can stay very hot for a
long time. Picking up the plugs
with an unprotected hand results in
a burn.
Another cause of burns is the grab-
bing of the probe as it leaves the
stack or duct. If gloves are not
used a burn will result from the 200
to 1000 °F probe. As in the case of
the plugs, it takes some time for
the probes to cool off. The larger
the probe, the longer it takes to
reach a safe temperature. Most
problems occur because of hot pitot
tubes.
SLIDE 4-6
~v*"w**^
This is the pneumatic solids hand-
ling system for a large hot side
electrostatic precipitator. The
solid material in the transport
pipes can have temperatures ranging
from 300 to 500 °F. Obviously,
these pipes should not be touched
while walking around the hopper
area. Since they are mounted close
to the gratings it is easy to brush
up against them by accident.
59
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SLIDE 4-7
This is the uninsulated roof of a
pulse jet collector on an asphaltic
concrete plant. The gas temperature
directly below these access hatches
is normally 325 °F. One sign of the
elevated gas temperatures is the
loss of paint on the access hatches.
Burns can occur while standing on
the roof or when reaching down to
remove the access hatch to one of
the compartments.
This slide shows a relatively mild case of a very common situation.
It is typical for the roofs of some collectors (or process equipment in the
area of the collector) to be at 400 to 600 °F. When climbing up to this
area, people tend to place their hands on the flat surface as they reach
the top of the ladder. In some cases, the plant personnel walk across a
hot area (e.g., top of boiler near the steam drum) to reach the air pollu-
tion control system or the measurement ports. Such shortcuts are never a
good idea.
SLIDE 4-8
Very serious burns can occur due to
steam. In some processes, very hot
steam is released intermittently. If
the inspector happens to be on an
elevated walkway or other exposed
area, a serious accident can occur.
In power stations, a high pressure
steam leak can pose a significant
risk. THESE LEAKS CANNOT BE SEEN OR
HEARD. THERE WILL BE NO APPARENT
CLOUD OF CONDENSED STEAM IN THE AREA
OF THE LEAK. When the plant alarm
indicates a high pressure steam
leak, the inspector should not move
around the boiler area. If outside
when the alarm sounds, the inspector
should not enter the boiler area.
The potential for steam burns is one of the reasons that it is impor-
tant for plant personnel to accompany an inspector at all times. Plant
representatives are familar with the intermittent operations which result
in a steam cloud and they generally know the protected locations. They
also know the procedures to be followed in the event of a high pressure
steam leak.
60
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SLIDE 4-9
This is the access hatch for a hop-
per on a baghouse. The solids in
the hopper are at 300°F and will
flow like water when the hatch is
opened. Serious burns can occur to
anyone in the immediate vicinity of
the hatch when it is opened. This
problem is easily avoided since the
inspector has no business being
close to a hatch being opened.
SLIDE 4-10
This is part of a chemical plant
handling large quantities of acid.
Chemical burns can occur from leaks
or sprays of acid. If a burning
sensation is felt on the head, do
not look up! Leave the immediate
area before attempting to locate the
source of the acid.
It is an instinctive response to
look up when a burning sensation is
felt on the head. If it is due to a
small leak above the inspector, the
acid may enter the eye.
61
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SLIDE 4-11
In
(GFIs),
This is a view of the roof of an
ambient monitoring station. The Hi-
Vol is directly above the field of
view of the slide. The power line
for the Hi-Vol motor is lying in a
puddle of water on the roof. This
situation could result in a fatal
shock because the person servicing
the unit would be standing in the
puddle with the power line in it.
All Hi-Vols should be equipped with
ground fault interrupters. When a
short circuit is sensed these shut
down the power in just a few milli-
seconds, before a fatal shock can
occur.
addition to equipping the Hi-Vols with ground fault interrupters
the power line should be removed from the puddle of water.
SLIDE 4-12
This is the electrical box for the
motor operating a rotary discharge
valve on a small baghouse. The box
cover has been partially removed and
the hot line is exposed.
Most people would not stick their
hand into an electrical box, however
in this case it could happen easily.
The area under the hopper of the
unit had a number of cross beams and
other obstacles. While trying to
get through this area, the box could
easily be grabbed. At the time the
box was grabbed, the individual
would probably be hanging on to one
of the metallic cross beams. It
would be possible to suffer a fatal
shock under these conditions.
As is so often the case, the various types of hazards occur frequently
in groups. Just 3 feet from the location of this slide, there is a missing
guard rail. While concentrating on ways not to fall off the guard rail, an
individual may not give any thought to the electrical hazard.
62
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SLIDE 4-13
When making measurements downstream
of electrostatic precipitators, it
is very important that all probes be
grounded. The highly charged part-
iculate leaving the precipitator can
impart a high static charge on the
probe. When the individual touches
the probe, a shock can occur. While
the static shock is usually not life
threatening, it may cause the person
to jump backwards and fall off the
sampling platform or hit his or her
head on the various obstacles often
found around the platform.
It is surprising how many stack samplers and field inspectors do not
respect the potential safety problems related to static electricity. It
is usually prudent to electrically bond all probes to the duct where the
port is located.
SLIDE 4-14
This is a electric vibrator type of
rapper on the roof of an electro-
static precipitator. There is a
small ground wire going from both
the box and the rapper shaft to a
grounding cable out of view of this
slide. This protects against shorts
in the vibrator which could
seriously shock anyone touching a
rapper.
Similiar grounding wires will be
attached to all bus ducts on the
precipitator roof. They are neces-
sary to drain off the charge which
builds up on the bus duct due to
sparking from the high voltage line
suspended in the center.
There is absolutely no need for the inspector to touch anything while on a
roof of a precipitator. It is possible to check rapper intensity and
sequence, to evaluate air infiltration through access hatches, and to check
the operation of the purge air blowers without touching any of the compon-
ents. Often contact will occur while a person is attempting to negotiate a
path across the roof which is crowded with bus ducts, conduit, rappers, and
transformer-rectifier sets. Although the very large majority of components
are properly grounded, contact with them should be avoided.
63
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SLIDE A-I
This is a partial view of the inside
of an electrical cabinet for one
field of an electrostatic precipita-
tor. On some older units, it is
necessary to open the cabinet to
determine if the field is on manual
or automatic control. This can be
determined from the position of the
switch shown in this slide. THE
CABINET SHOULD BE OPENED ONLY BY
QUALIFIED PLANT PERSONNEL, NEVER BY
THE INSPECTOR. Electrical compo-
nents within easy reach can be at
more than 400 volts.
Hazards from electrical cabinets also occur when inspectors attempt to
measure the fan motor currents for scrubbers and baghouses. Opening an
electrical cabinet to use an inductance ammeter should be done only by
qualified plant personnel, never by the inspector. As with the cabinet
shown above, they can have high voltage components around the lines being
measured.
SLIDE 4-16
When walking around areas where
flammable vapors are possible, in-
spectors should wear safety shoes
designed to prevent the accumula-
tion of static electricity. Before
inspecting areas similar to that
shown in this slide, discuss the
type of shoes to be worn with plant
personnel.
Source: National Audiovisuals Center
64
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SLIDE 4-17
Most plants have areas where explo-
sions could be initiated by smoking.
While the plant personnel are warned
repeatedly about such areas, the
inspector may not recognize the
hazard. DO NOT TAKE SMOKING MATER-
IALS ON INSPECTIONS.
SLIDE 4-18
This is a portable thermocouple for
measuring gas temperature. It is
one of a number of common inspection
instruments powered by batteries.
It should not be taken into poten-
tially explosive areas because it
can initiate an explosion.
It is necessary to obtain a hot work
permit is necessary to take battery
powered instruments in to areas
around some air pollution control
systems. Potential problems should
be discussed fully before taking
the instruments into such areas.
The most common types of battery-
powered instruments are pH meters,
flashlights, and thermocouples.
65
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SLIDE 4-19
It is sometimes necessary during an
inspection to get a sample of a sol-
vent or coating to analyze for vola-
tile content. It is also common to
get a sample of fuel oil to measure
the sulfur content.
When transferring flammable liquids
or dusts from a storage vessel to a
sample container it is possible to
build up a high static voltage on
the receiver. If the entire system
is not grounded and bonded properly,
an explosion is possible.
This slide shows a storage drum and the small clip which is meant to
be attached to the receiver. This particular clip is so rusted that it is
very unlikely that it could provide a proper electrical connection.
When drawing a sample, the funnel (if any) must be made of a con-
ductive material and must be electrically bonded to the rest of the system.
It is also important to prevent static electrical sparks originating from
persons near the sample container. The samples should be drawn by plant
personnel, not the inspector.
SLIDE 4-20
This is another view of the storage
drum shown in the previous slide.
Close examination reveals that the
line leading from the grounding
stake is not connected to the
storage drum. Since the storage
drum, funnel, and receiver may not
be at the same potential, an explo-
sion is possible.
Whenever it is noted that grounding
and bonding are incomplete, the in-
spector should notify responsible
plant personnel immediately. If the
plant personnel persist in taking
the sample, the inspector should
leave the area immediately.
66
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SLIDE 4-21
This is a relatively small fan on a
wet scrubber system. If a fan ap-
pears to be vibrating severely, the
inspector should notify responsible
plant personnel immediately and
leave the area. When a fan disinte-
grates, metal shrapnel-like frag-
ments can be sent over a wide area,
even through walls.
Excessive fan vibration can occur
because of aerodynamic conditions or
various physical insults. The most
common physical problems include
bearing failure, wheel erosion, and
wheel deposits. Operating a fan at
too high a speed can also cause the
fan to disintegrate.
Fan disintegration often occurs during start-up of the unit. It is
generally prudent to stay some distance away from fans when they are being
started.
SLIDE 4-22
HIGH VOLTAGE LINES
High voltage tracks are common at
steel mills and other plants in
which it is necessary to move hot
material on a routine basis.
The high voltage line can be within
reach while walking through the
mill. Even though there are warning
signs, inspectors not familiar with
the plant could conceivably touch
the line. In some plants, it would
be possible to accidently step on
these high voltage tracks.
High voltage lines are sometimes
found in the vicinity of air pollu-
tion control devices and stacks.
Care is necessary whenever using
long measurement probes such as
pitot tubes.
67
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SLIDE 4-23
Many air pollution control systems
are located at the highest locations
within the plant. Lightning can
strike the structures in the area of
the collector. Whenever threatening
weather exists, these exposed
locations should be avoided. Avoid
these exposed locations when the an
electrical storm is in the area.
SLIDE 4-24
There are several possible ways to
be exposured to ionizing radiation
such as gamma rays and beta partic-
IONIZING RADIATION les. Gamma ray sources are used as
hopper level detectors on some large
electrostatic precipitator and fab-
ric filter systems. Gamma ray in-
struments are used to continuously
monitor process feed rates, material
densities, and tank levels. Beta
gauges are used for the continuous
monitoring of film thickness.
It has also been reported that some dusts collected in air pollution
control systems are somewhat radioactive because of the components of the
ash or dust. It should be easy for an inspector to avoid any significant
exposure to ionizing radiation.
68
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SLIDE 4-25
This is the source part of a gamma
ray detector on the hopper of an
electrostatic precipitator. It con-
tains a small amount of cesium 137,
a radioactive substance. Cesium 137
is constantly disintegrating by re-
leasing gamma rays. The gamma rays
are focused into a narrow beam
which passes to a detector on the
other side of the hopper. The pre-
sence of solids in the hopper is
indicated by the absorption of some
of the gamma rays.
All instruments of this type have a shutter which prevents release of
the gamma rays when maintenance is being performed (the source can not be
"turned off"). The entire source is shielded to reduce exposure to gamma
rays in the immediate vicinity of the monitor. All instruments must
satisfy a minimum radiation level within one foot of the instrument. Be-
cause of these design characteristics, the instruments are considered safe
for a number of applications. Nevertheless, the regulatory agency inspec-
tor has no need to be close to the instruments and should avoid close
contact. If a detector has been damaged , the entire area surrounding the
Monitor should be avoided because the protective shielding may no longer be
effective.
SLIDE 4-26
""""' mmmft
'
This is a gamma ray sludge feed
monitor at a sewage treatment plant.
The source of gamma rays is located
in the arm above the belt and the
detector is located below the belt.
The quantity of solids is related to
the gamma ray absorption.
It is obvious that placing hands or
arms between the source and the
detector. would result in direct
exposure to the gamma ray beam. It
would also bring the individual into
contact with moving equipment.
This type of instrument is shown because (1) it is the most common
of gamma ray source found during inspections of air pollution sources
(2) it has the largest open path between the source and the detector.
is no reason for an air pollution control agency inspector to be in
immediate vicinity of any of these instruments.
-------
SLIDE 4-27
Direct contact with large quantities
of collected solids (or even coal
piles) should be avoided. There is
a very slight possibility that some
of these will have significant rad-
ioactivity levels. There are also a
number of other accidents and health
hazards associated with large piles
of dust and solids (burns, skin
irritation, falls, asphyxiation, in-
halation of toxic dust, entrapment
in submerged rotating equipment).
70
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SLIDE 5-1
HEAT STRESS
Many air pollution control systems
operate at elevated gas temperatures
and many operate in close proximity
to hot process equipment. Steam
clouds are common near control de-
vices. Furthermore, the areas which
must be inspected are generally in
the highest parts of the plant which
means that climbing is almost inevi-
table. Due to these factors, heat
stress is a potential threat to the
inspector. This lecture concerns
recognition of the symptoms of heat
stress onset and ways to minimize
the risk of heat-related injuries.
HEAT SOURCES
• Steam
• Ambient Temperature
• Radiant Energy
• Metabolic Heat
SLIDE 5-2
Heat stress is the additional load
placed on bodily functions as the
body attempts to maintain correct
internal temperatures. This is not
easy; there are significant sources
of heat present in every industrial
setting. This slide lists the four
most common heat sources encountered
during the inspection of air pollu-
tion control systems.
Radiant heat from hot ducts, control
devices and process equipment can be
a significant problem. The level of
heat radiation is related to the
FOURTH POWER of the temperature of
the hot equipment. -This means that
uninsulated equipment in the range
of 300 to 2000 °F can radiate very
large heat levels.
Metabolic heat is the energy released during heavy work such as climb-
ing, breathing with respirators, taking measurements, and lifting portable
inspection equipment.
Steam is very common around air pollution control systems and can be a
major source of heat energy . Steam makes the normal bodily cooling func-
tions difficult because it raises the humidity in the vicinity of the
control system. These varied sources of heat make it possible to suffer
heat stress even when the ambient temperature is relatively low.
71
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SLIDE 5-3
It is possible for the inspector to
suffer the onset of heat stress
while plant personnel seem to be
ACCLIMATIZATION TO HEAT having no difficulties at all. In-
spectors are often more susceptible
to heat stress because it is not
possible for them to acclimate to
plant conditions.
Acclimatization involves actual
physiological adjustments of the
body and results in enhanced toler-
ance to heat. It usually takes one
to two weeks of exposure for total
adjustment.
The majority of the changes involved in acclimatization take place
during the first two days. Unfortunately, the enhanced capability to
with-stand heat is also lost quickly as most body readjustments occur in
just two days. Therefore, the agency field inspector does not remain
acclimated even though he or she is regularly exposed (once a week) to hot
conditions.
SLIDE 5-4
FACTORS WHICH INCREASE
SUSCEPTIBILITY TO HEAT STRESS
Lack of Acclimatization
Chemical Exposure
Noise Exposure
Obesity
Age
Mean or Respiratory Disease
Alcohol Consumption
Fatigue
Humidity
Altitude
Factors which can contribute to heat
stress include exposure to chemicals
such as carbon monoxide and exposure
to excessive noise. The physical
condition of the individual is also
important. Conditions such as obe-
sity, heart disease, alcoholic con-
sumption, and fatigue can aggravate
the conditions. Susceptibility to
heat stress usually increases with
age.
72
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SLIDE 5-5
HEAT-INDUCED ILLNESSES
• HEAT CRAMPS
• HEAT EXHAUSTION
• HEATSTROKE
The three major heat induced ill-
nesses are listed in order of in-
creasing severity. A brief synopsis
of the symptoms of developing prob-
lems and emergency treatment for
each problem are discussed in the
following slides.
SLIDE 5-6
HEAT CRAMPS
Cause: Loss of Salts
Symptoms: Muscle Spasms
Treatment: Rest and Drink Water with 0.
Salt
Sweating causes depletion of salts
from the body vwhich in turn reduces
tissue fluid levels and causes mus-
cle spasms. The spasms are most
common in the extremities, back,
and abdomen.
If these symptoms are experienced,
the inspection should be interrupted
immediately and a cool place to rest
should be found. The affected indi-
vidual should drink water contai-
ning 0.1% by weight salt (1 teaspoon
per 5 quarts water).
73
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SLIDE 5-7
Heat exhaustion results from the
loss of body water and salt. The
dilation of blood vessels results
in decreased blood circulation and
reduced blood supply to the cerebral
cortex. This can cause an indivi-
dual to collapse.
The initial symptoms include rapid
pulse with low blood pressure, head-
ache, nausea, fatique, clammy skin,
and vomiting. Obviously, all in-
spection activities should be stop-
ped and immediate aid obtained when
these symptoms are noticed.
The individual should rest in a cool place which is not less than 75°F.
It may be necessary to get further treatment from plant personnel or other
qualified medical personnel.
HEAT EXHAUSTION
Cause: Decreased Blood Circulation from
Dehydration and Vasodilation
Symptoms: Fatigue, Nausea, Vomiting,
Headache, Dizziness, Clammy
Skin, Fainting, Rapid Pulse, Low
Blood Pressure, Mental
Disturbances
Treatment: Rest in Cool Area, Drink Water
with 0.1% Salt, Get Medical
Attention
SLIDE 5-8
Heat stroke is an extremely serious
condition. It is caused by the
failure of the body cooling system
and the uncontrolled rise in body
core temperature. It can be fatal
if not treated promptly.
The symptoms are a hot, dry skin,
high body temperature, confusion,
convulsions, loss of consciousness,
and coma.
The treatment usually consists of
immediate cooling by immersion in
chilled water with massage or wrap-
ping in wet sheets and fanning. It
is often necessary to treat for
shock.
It should be apparent that medical aid should be obtained as rapidly
as possible when there is a possibility for heat stroke. It should be re-
memebered that most air pollution control equipment is located in elevated
and remote portions of the plant. It may be difficult to rapidly move an
unconsciousness individual to a cool air and difficult to get cool water up
to a stricken individual. For this reason, it is necessary to start for
protected areas and medical attention at the first sign of trouble.
HEATSTROKE
Cause: Failure of Perspiration System
Resulting in Rise in Body
Temperature
Symptoms: Hot, Dry Skin; High Body
Temperature; Loss of
Consciousness; Convulsions;
Coma
Treatment: Immediate and Rapid Cooling, Get
Medical Attention, Treat for Shock
if Necessary
74
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SLIDE 5-9
One way to minimize the risk of the
various types of heat stress just
discussed is to avoid hot areas as
M.N.M.Z.NO THE R.SK OF HEAT STRESS Z^^g^ the'i^ti
hot sources during the early part of
the day when the ambient tempera-
ture is low. While walking to the
control systems, avoid the the hot
areas of the process. Some of the
most common areas which are hot are
walkways near furnaces and rotating
kilns, and the roofs of air pollu-
tion control devices.
Pitot traverses on hot ducts can sometimes be a cause of heat stress
since the inspector could spend up to an hour at the sampling ports. If it
is necessary to be close to the stack or duct during the traverse, there
Can be substantial exposure to heat. One way to minimize problems is to
mark off the probe and perform all calculations in an area which is cooler
than the sampling platform. If the radiant heat is very high, the pitot
traverse should not be conducted at this location.
All inspectors should be screened for hot weather work as part of a
medical monitoring program. This should identify any individuals with
Problems such as heart and respiratory diseases or any other condition
which makes that person particularly susceptible to heat stress problems.
SLIDE 5-10
When working near a radiant source
of heat, such as a duct or stack,
protective clothing may be necessary
SELECTING THE APPROPRIATE CLOTHING to reduce the potential exposure.
When working near nonradiant sources
of heat light clothing should be
worn so that evaporative cooling is
facilitated. In general, when the
temperature is less than 100 °F the
clothing should be light and loose
fitting. When the temperature is
greater than 100 °F, it should cover
as much of the body as possible to
decrease convective heat transfer
from the surrounding air.
Synthetic materials should not be worn in areas where there is high
radiant heat. It is possible for some of the synthetics to bond to the
8kin when the temperature is very high. The work clothes should be com-
Posed primarily of cotton.
75
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SLIDE 5-11
Individuals working in hot areas
must drink sufficient fluids to re-
place that lost through sweating.
Nonacclimated people must take the
GENERAL PRECAUTIONS TO MINIMIZE precaution of increasing their salt
HEAT STRESS intake to avoid dehydration. Heat
cramps can result from drinking
large quantities of unsalted water
because of the muscle tissue fluids
become diluted. Salt may be taken
with meals, in electrolyte beve-
rages, or in salted water. Fluids
should be taken every 30 minutes and
one person may consume up to 2 gal-
lons per day.
Another precaution that can be taken to reduce the chance of heat
stress is to take frequent rest breaks when working in hot areas. The work
should be interrupted whenever symptoms of the onset of heat stress are
observed.
SLIDE 5-12
Cold stress is the loss of body heat
in situations of overexposure to
COLD STRESS cold. It can lead to skin injury,
loss of extremities, and even death.
For air pollution control inspec-
tors, the principal problem is skin
injuries.
76
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MECHANISMS
OF
BODY HEAT LOSS
• Radiation
• Conduction
SLIDE 5-13
The five mechanisms for loss of body
heat are listed in this slide. The
radiation to surroundings increases
substantially as the ambient temper-
ature drops. This is again a funct-
tion of the fourth power of the
person's temperature and the sur-
rounding temperature. Conduction
occurs while standing in a layer of
water or while holding on to cold
objects (such as guard rails and
support beams).
The convective transfer of heat from the body increases as the wind
speed increases. It is important to stay in protected areas to minimize
this mode of heat loss. Respiration results in heat loss since the cold
air is heated to body temperature before it is released.
Convection
Evaporative Cooling
Respiration
SLIDE 5-14
FACTORS WHICH INCREASE
SUSCEPTIBILITY TO COLD STRESS
• Lack of Habitation
* Heart and Respiratory Conditions
• Fattgue
• Alcohol Consumption
• Inadequate Food
• Dehydration
Some of the factors which affect an
individual's susceptibility to cold
stress are listed in this slide.
People do not acclimate to cold as
they do to heat, however, there is
some habituation, that is, in-
creased tolerance for cold condi-
tions.
Individuals with heat and/or res-
piratory problems will be more at
risk from cold stress than others.
Alcoholic consumption should be min-
imized. Fatigue, inadequate food,
and dehydration also make an indi-
vidual more susceptible.
77
-------
COLD INDUCED AILMENTS
• FROSTBITE
• HYPOTHERMIA
SLIDE 5-15
These are the two major ailments
caused by extremely cold conditions.
Frostbite is the freezing of some
part of the body. Ice crystals form
in the cells of the affected tissue.
Usually this occurs in the extrem-
ities such as ears, hands, and parts
of the face. There are three de-
grees of frostbite: frostnip, sup-
erficial frostbite and deep frost-
bite. Frostnip affects only the
skin while superficial frostbite can
affect tissue just below the skin.
Deep frostbite affects deep tissue
including even the bones.
Hypothermia is the lowering of the body's core temperature. This can
result in mental and physical deterioration to the point of collaspe. It
is often fatal.
SLIDE 5-16
FROSTBITE SYMPTOMS
Frostnip: Red to Pate or White Skin,
Tingling, Stinging or Cold
Sensation Followed by Numbness
Superficial Frostbite: White to Grey-White Skin. Waxy
Skin and Lack of Sensation
Deep Frostbite: Skin and Tissue Pale, Solid
Blisters and Swelling
The symptoms of frostbite are list-
ed in this slide. Note that there
is a progression in the type and
severity of these conditions.
Whenever these symptoms are noted,
the inspection should be stopped and
a protected location found.
78
-------
SLIDE 5-17
TREATMENT OF FROSTBITE
Frostnip: Apply Body Heat
Superficial Frostbite: Apply Body Heat
Deep Frostbite: Remove to Warm Area, Bathe
Affected Area with Warm Water or
Apply Warm Packs, Qet Medical
Attention
The immediate treatment of frost-
bite is listed in this slide. To
treat frostnip, apply body heat by
placing the affected part in direct
contact with skin of an area which
is warm, such as the chest or arm-
pit. The treatment for superficial
frostbite is identical to that for
frostnip.
For deep frostbite, the person
should be removed to a warm area and
the affected area bathed in warm
water (between 104 and 106 °F). An
alternative to bathing the area is
to use wet packs.
SLIDE s-is
SYMPTOMS OF HYPOTHERMIA
>95° Uncontrollable Shivering and
Increase In Respiration
90-95 °F Disorientation, Apathy, Dilated
Pupils, Diminished Shivering and
Diminished Respiration
86-90 °F Semi-Consciousness, Muscular
Rigidity and Further Pupil Dilation
<86 °F Unconsciousness and Diminished
Respiration
<80°F Little or No Respiration
The symptoms of hypothermia change
with the body's core temperature.
There is a logical progression as
the core temperature drops.
As the body temperature drops to
95°F, shivering increases to uncon-
trollable levels and respiration
increases.
Between 90 and 95 °F, disorientation
and apathy occur. Diminished shiv-
ering and respiration occur. The
pupils become dilated.
Between 86 and 90 °F, there is muscular rigidity and further dilation
°f the pupils. Semi-consciousness may occur. Below 86 °F, respiration is
very diminished and the person may be unconscious.
The treatment of very mild hypothermia consists of feeding warm beve-
tages and replacing all wet clothing with dry. In more severe cases, the
Person should be placed in a warm bath (approximately 105 °F) or wrapped
with warm moist towels. Medical aid should be obtained immediately.
79
-------
SLIDE 5-19
WINOCHILL CHART
MNO8K8O
IMFH)
8
10
16
10
26
30
38
40
48
80
32
28
18
13
7
3
1
-1
-3
-3
-4
23
20
7
-1
4
-to
-13
-IB
-17
-16
-18
14
10
-4
-13
-16
-24
-27
-28
-31
-32
•33
VK*(
8
t
-16
-38
-32
-37
-41
-43
-48
-48
-47
HI*
-4
4
-28
-37
-44
40
-«
47
48
41
42
ffflA
-13
-18
-37
-48
47
+*
48
-71
-74
-76
-78
TVfl
-32
-28
-48
41
-70
-77
42
48
47
48
41
1 F)
-31
-37
48
-73
43
40
47
48
-103
-1O4
-108
-40
-47
-70
48
46
-104
-108
-113
-116
-118
-120
-48
46
41
47
-108
-117
-133
-137
-131
-132
-134
-"
48
42
-108
-121
-130
-137
-142
-146
-147
-148
For Property CMtatf Unto ConiiamMi Vwv On« DWK
Fran Dnpf Ow«v
OANOIM FROM FREEZING OF 8XFO88D FL88H
Routine inspections of air pollu-
tion control equipment should not be
done when the wind chill factor is
less than -20 °F. The chart shown
on this slide allows a calculation
of the wind chill factor using the
temperature and the wind speed.
At wind chill factors greater than
the -20 °F there is little danger,
for people who are properly clothed,
that exposed flesh will freeze.
Below -20 °F, there is the risk of
cold stress. It is also possible
that observations and measurements
made under very cold conditions will
not be complete or accurate. Some
portable instruments are not inten-
ded for service under very cold
conditions.
SLIDE 5-20
Clothing should be layered to trap
warm air and to prevent conductive
heat loss. In addition, layering
SELECTION OF APPROPRIATE CLOTHING allows regulation of warmth. When
it gets too warm, one simply takes
off the appropriate layers. The
outer layer should be wind proof,
and in wet weather, water proof.
Wet clothing causes rapid loss of
body heat due to evaporative cool-
ing. The inspector should be aware
that heavy perspiration may dampen
clothing enough to cause evaporative
cooling. Heat regulation can be
accomplished by removing layers and
by opening closures at neck and
wrists.
The head should always be covered since substantial heat loss occurs
through the head. Insulated boots should be worn. Steel toed boots can
cause rapid chilling of the feet.
80
-------
SLIDE 5-21
During the inspection, the work
outside should be alternated with
the work inside so that long periods
GENERAL PRECAUTIONS TO MINIMIZE THE ^l*** ^ "Ot T* in
DICK nc rni n CTRP«5R areas. While inside, warm
RISK OF COLD STRESS should be consumed to help warm the
body. The clothing should not be-
come damp from perspiration while in
the warm areas.
Regular checks for the onset of
frostbite should be made. The in-
spector should not, under any cir-
cumstances, work alone. An accident
could trap an inspector in an iso-
lated portion of the plant and re-
sult in extended exposure to cold
before he or she is found.
81
-------
82
-------
SLIDE 6-1
A wide variety of potential hazards
may be encountered while inspecting
air pollution control systems. Un-
like workers who might work at the
same station for 40 hours per week,
inspectors are not usually subject
to chronic exposure to the same
chemicals. Rather, they are poten-
tially at risk from acute exposures
to a large number of chemicals. It
is important for each inspector to
know the warning properties of these
chemical and how to choose
respirators which will provide pro-
tection from various types of chem-
icals and different concentrations.
One of the fundamental principles of industrial hygiene is that possi-
ble exposures should be minimized or eliminated through the application of
engineering controls. In the case of the field inspector for a regulatory
agency this is not a realistic possibility. Most exposures occur because
of fugitive leaks of the pollutant-laden gas stream out into the area
immediately surrounding the air pollution control system. These conditions
occur by accident and often are not identified by plant personnel. Other
sources of exposure are contact with the downd'raft from nearby stacks or
rising clouds of toxic pollutants released from intermittent process opera-
tions. Both types of exposure result when inspectors are present on ele-
vated platforms surrounding air pollution systems or stack sampling loca-
tions. In a sense, the inspector is at risk from the discharge points of
the very engineering controls which are intended to protect plant person-
nel.
Since the exposures can not be easily limited by engineering controls,
the inspector must substitute awareness of the potential problem areas and
awareness of the warning properties of all chemicals present in the gener-
al area. The inspector must know when certain areas should be avoided and
what respirators and other protective clothing to use in the areas which
must be visited. The choice of respirators is complicated by the lack of
monitoring data for the types of materials present. The conditions are
highly variable and this makes monitoring data subject to error. Further-
more, there is rarely any monitoring data in the specific locations where
the inspector may experience the most significant exposure.
The inspector who fails to use a respirator when necessary or selects
the improper respirator can be at substantial risk. Synergistic action
between the 300 to 600 common chemicals that may be inhaled by a single
individual during a year could result in problems despite the small quan-
tites of each that may have deposited in the respiratory tract. Also, if
the inspector is hypersensitive to any chemical, he or she has a good
chance of encountering this material at least once per year. The inspector
does not ever get an opportunity to acclimate to the various chemicals.
83
-------
SLIDE 6-2
This is one of three basic rules
that field personnel should follow
P°11Uti°n
EVERY SITUATION SHOULD BE
APPROACHED CAREFULLY
This rule means that the inspector
should bring the proper personal
protective equipment necessary for
the areas to be inspected. The
agency file for the plant should be
reviewed before starting the inspec-
tion. Files should contain lists of
the chemicals which could be encoun-
tered during the inspection. Based
on the list and the recommendations
of the plant personnel, the proper
type of respirator can be selected.
Prior to entering each specific area of the plant, the inspector
should consider what potential problems can exist. Partially confined
areas should be avoided to the extent possible. While walking to the area
of the pollution control equipment, avoid plant operations not directly
related to the inspection.
SLIDE 6-3
The work should be interrupted when
the inspector encounters any of the
non-specific symptoms of exposure
listed in this slide. While these
ill feelings may not be due to any
exposure which occurred at the
plant, the inspector can not afford
to base his actions on this assump-
tion. The inspector should go IMME-
DIATELY to a well-ventilated area
and reconsider the potential inhala-
tion hazards. Remember that the
inspector may feel ill before the
plant personnel because they accli-
mated to the conditions and are not
exposed to as wide a variety of
materials as the inspector.
It is important that the inspector be aware of how he or she is feel-
ing during the inspection. Many of the pollutants have very poor and non-
specific warning properties. The initial mild feelings of discomfort can
quickly develop into very serious situations. At the first feeling of
discomfort, the inspector should go to a well-ventilated are immediately.
HALT WORK IMMEDIATELY
IF YOU HAVE ANY
OF THESE SYMPTOMS:
Headache
Nausea
Drowsiness
Chest Pains
Shortness of Breath
Lightheadedness
Eye or Nose Irritation
Find A W«n Ventilated Area Immediately
84
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SLIDE 6-4
IF THE NECESSARY PERSONAL PROTECTIVE
EQUIPMENT IS NOT AVAILABLE THEN AREAS
OF POTENTIAL RISK MUST BE AVOIDED
This is the third basic rule. If
the necessary protective equipment
is not available, or if the inspec-
tor does not have the proper train-
ing in the use of this equipment, no
areas of potential risk should be
entered.
One might expect that plant person-
nel would restrict entry to such
areas. However, in a few cases they
do not recognize that these are haz-
ards since they are so familiar with
the conditions. Furthermore, the
inspector should not abdicate all
responsibility for safety to anyone
else during an inspection.
Plant personnel often provide the necessary respirators to inspectors
without realizing that the individual has had no previous training in the
use of the respirators and has not had a medical examination to demonstrate
his capability to withstand the stress caused by the respirator. The
inspector should advise plant personnel in either case and the areas of
Potential exposure should be avoided. This will probably mean that a large
Portion of the inspection can not be done as planned.
SLIDE .6-5
The upcoming series of slides con-
cern the most common areas where
exposure to chemicals can occur when
inspecting air pollution systems.
The inspector must recognize these
areas so that potential exposures
can be avoided entirely or minimized
by using respirators.
The list presented in this slide
presents some of these common areas.
It is readily apparent that most
sources include a number of such
areas.
The term "partially confined area" has been developed for this pro-
gram and will not be found in the standard industrial hygiene literature.
This phrase is necessary to characterize the unique hazards which can be
found near air pollution control systems. Such areas must be approached
cautiously.
COMMON AREAS WITH
INHALATION HAZARDS
• Elevated Sampling Platforms
• Areas Adjacent to Process Vents and Discharge Pofnts
• Partially Confined Areas
• Fugitive Process Emissions
• Fugitive Emissions from Solids Discharge Equipment
85
-------
SLIDE 6-6
m*
This is a photograph of a stack
sampling platform on a foundry wet
scrubber system. Out of view to the
right of the slide are several small
roof monitors which vent the process
operations below. The emissions can
drift across the sampling platform.
An inspector could spend more than
an hour on the platform while making
a pitot traverse. Stack samplers
could easily spend 6 to 10 hours on
the platform while performing a com-
plete Method 5 test.
Due primarily to the length of the possible exposure, the proximity to
the process vents, and the toxicity of the pollutants released from the
vents during certain periods, it is advisable to use respirators. Stack
samplers may need to take frequent breaks to reduce the discomfort of the
respirators cause over a 6-10 hour period. Field inspectors should at-
tempt to find a different location for making the pitot traverse. If this
is not possible, then all activities associated with the traverse that do
not have to be conducted directly at the sampling platform should be done
in a protected location. For example, it would be easy to calculate the
number of points necessary and to mark off the pitot tube at a remote
location. Only the measurement of the stack diameter, and the measurement
of the velocity pressures and gas temperatures need be done on the plat-
form. Generally, about one half the time involved in a Method 2 traverse
can be spent away from the platform.
SLIDE 6-7
This is a photograph of several in-
spectors preparing to make a gas
temperaturfe measurement at a 4 inch
diameter port on the duct leading
from the induced draft fan. At this
location, the static pressure is
between one half and one inch posi-
tive pressure. Even at this low
pressure, a substantial quantity of
the gas can escape from the port
into the breathing zone of the peo-
ple. The cloud of gas is visible in
the left center of the slide.
These large diameter ports should be avoided, especially when the
static pressure of the gas is positive. The port should be one half to one
inch in diameter to minimize the flow rate of gas through the port. Only
ports with good ventilation should be used in any case. Before opening the
port, the inspector should put on the appropriate respirator.
SLIDE 6-8
86
-------
SLIDE 6-8
This is the discharge duct from a
medium sized fabric filter. The
duct is horizontal and is pointed at
the platform surrounding an adjacent
fabric filter. Some of the parti-
culate matter handled by the unit
shown in the slide is highly toxic.
If there were a sudden bag failure,
there would be undesirable levels of
this material in the area where an
inspector might be.
It is very common for the baghouse
discharge to be very low to the
ground with either a horizontal or
downward orientation. In other
words, many stacks do not point up!
Sudden malfunctions of air pollution
control devices occassionally happen.
The inspector must be aware of all the pollution control system dis-
charge points and all process vents. It is necessary to be constantly
aware of the best way to leave the area rapidly and it is advisable to have
a respirator available at all times.
This photograph shows a modern as-
phalt concrete plant. The "stack"
for the baghouse is the rectangular
vertical duct on the right side of
the baghouse. It is apparent that
the inspector must walk right next
to the discharge point (at the same
elevation as his or her feet) while
going to check the operation of the
diaphragm valves and the condition
of the top hatches. A cross wind
would easily carry the exhaust to
the breathing zone of the inspector.
Unfortunately, emissions from asphalt concrete plants do not have a
high opacity even when the rate of emission is above the regulatory limit.
Therefore, inspectors could underestimate the quantity of material they
are being exposed to.
A baghouse does not remove any gases and vapors! Many asphalt plants
(and other facilities) have moderate concentrations of sulfur dioxide and
other contaminants which easily pass through the baghouse.
87
-------
SLIDE 6-10
This is a view of a top of a cupola
at a foundry. It is very abnormal
for the top to be open and the
emissions to be escaping to the at-
mosphere without any control at all.
The upset at this plant occurred due
to failure of the induced draft fan
in the air pollution control system.
The emissions include particulate
matter, carbon monoxide, sulfur di-
oxide, and partially combusted or-
ganic vapors.
It is very probable that the inspector would be on site during this
time in response to the malfunction report called in by the plant person-
nel. The area fumigated by the plume from the upset process equipment must
be avoided. Sudden changes in the wind direction can result in exposure to
the highly contaminated plume.
SLIDE 6-11
This is a photograph of the same
plant shown in the above slide. It
was taken approximately 30 seconds
after the above picture. The plume
from the cupola discharge has been
caught in a downdraft and begun to
fumigate the area where the plant
environmental manager and the in-
spector were located. The picture
was taken from a sheltered area out
of the direct path of the plume.
Inspectors should always be aware of
the location of the plume during
such periods and should avoid areas
where they might be trapped as the
plume passes.
Inspectors should always be aware of the best means to escape an area
which is suddenly in the path of the plume. It may be impossible to see
due to the irritating properties of many pollutants. The inspector may
experience difficulty in breathing. The potential problems related to
falls from elevated surfaces (discussed in Lecture #2) become even more
serious under such conditions.
88
-------
This appears to be an innocuous
barrel of solids directly below the
hopper of a baghouse. A gust of
wind can entrain a cloud of the dust
and blow it right into the face of
an inspector. It is common for the
composition of such dusts to be 1%
to 5%, by weight, toxic metals, such
as lead cadmium and/or zinc.
SLIDE 6-13
This is what a manufacturing opera-
tion will look like when the fabric
filter (or other control system) has
failed. Due to the poor ventilation,
the concentration of contaminants
can increase rapidly. It will be
necessary to wear a respirator in
areas which usually do not require
respirators. The inspector should
make every effort to minimize the
time he or she spends in the affec-
ted area.
Source: National Audiovisuals Center
89
-------
SLIDE 6-14
There are moderately heavy deposits
on the floor in this portion of the
plant. Walking through this area to
reach the air pollution control de-
vice will stir up this material.
The inspector should usually wear
the same type of respirator as the
personnel working in this area are
using. This area should be avoided
if there is an alternate route to
the collector.
Source: National Audiovisuals Center
SLIDE 6-15
High concentrations of toxic chem-
cials and asphyxiants can occur in
any "partially confined area". This
"PARTIALLY" CONFINED AREAS is an area outside of any equipment
where there is poor air movement.
Fugitive leaks of pollutant gas from
the air pollution control system can
result in very undesirable levels of
the pollutants. These areas should
be avoided if at all possible. If
it is necessary to go through these
areas, some kind of protective
equipment is often necessary.
There are numerous partially confined areas around control devices.
Not only can the trapped pollutants cause acute respiratory problems, but
also the inspector is more susceptible to physical injuries because the
exposure may cause symptoms such as lightheadedness which sometimes accom-
pany the exposure.
The problems with partially confined areas are most severe when the
collector is under positive pressure. Since the pressure in the unit and
ductwork is above the pressure of the outside air, any leak can result in
high concentrations of pollutants in the immediate vicinity of the pollution
control system components.
90
-------
SLIDE 6-16
This is a side view of the roof of a
precipitator. There is a structure
immediately above the precipitator
which restricts natural ventilation
on the roof. The unit is under pos-
itive pressure and there are leaks
up into the roof area.
In some cases, it is necessary to
spend up to several hours on the
roof of precipitators like this, to
check rapper sequence and inten-
sity. Obviously a respirator would
be necessary.
Areas like this are prone to pollutant build-up when the wind is calm.
It is important to be especially cautious on these days. The types of
gases which are common on electrostatic precipitator roofs include sulfur
dioxide, nitrogen oxides, carbon monoxide, and ozone. Ozone is generated
by ultraviolet photolysis of molecular oxygen by the corona on the pre-
cipitator wires. The gas streams normally have an oxygen content between
3% and 10%. For this reason, it is also possible to encounter an oxygen
de-ficient atmosphere (defined as < 19.5% oxygen) in partially confined
areas on the precipitator roof.
SLIDE 6-17
This slide shows the lower portion
of one collection plate rapper of
the unit shown previously. There is
an obvious leak around the rapper
seal. This is the main source of
the pollutant laden gas entering the
partially confined area of the roof.
It is usually not possible to see
these leaks. In this case , the
moisture in the leaking gas conden-
sed rapidly, marking the location of
the leaks.
It is difficult to find and eliminate all of the leaks on a large
electrostatic precipitator. Some have a roof area which is close to the
size of a football field. There can be several hundred plate rappers (as
shown in this slide) and large numbers of discharge electrodes and gas
distribution screen rappers. Access hatches on the precipitator roof are
also potential leak sites. It should be assumed that leaks exist on all
Precipitators under positive pressure.
91
-------
SLIDE 6-18
This is a view looking down on the
roofs of two precipitators which are
in an arrowhead arrangement. The
stack is in the upper left of this
slide. The white structures are
weather enclosures over the roofs of
the units. In colder climates, the
weather enclosures facilitate main-
tenance. Even with the ventilation
fan, common in such enclosures, it
is possible to find high concentra-
tions of pollutants within these
structures.
The inspector should wear the same type of respirator used by plant
personnel in these areas. It should be noted that these enclosures are
generally desirable in that precipitator maintenance and precipitator long
term performance are enhanced. They should not be discouraged solely be-
cause of some possible discomfort to the inspector. There may be a need
to measure the pollutant and oxygen concentrations prior to entry. If the
inspector does not have the necessary safety equipment to enter this area,
then the inspection must be abbreviated.
SLIDE 6-19
This is a picture inside a weather
enclosure around the hoppers of an
electrostatic precipitator. Pollu-
tant laden gas may leak through
the access hatches and weld gaps in
the hoppers leading to high pollu-
tant concentrations in this area.
Again, it is necessary to test the
oxygen level and the pollutant con-
centration prior to entry.
There is rarely a good reason for an
inspector to enter the enclosures
around hoppers of precipitators
under positive pressure. Checks for
air infiltration are necessary only
on negative pressure units. The
only other items of interest are
provisions to prevent solids
overflow in the hoppers. These can
be seen from the access door to the
enclosure; it is not necessary to
enter.
92
-------
SLIDE 6-20
Source: National Audiovisuals Center
This is a multiple compartment bag-
house under positive pressure. The
walkway between the compartments can
have very high pollutant concentra-
tions and low oxygen levels if the
access doors, shell, or ducts leak.
Some of these walkways are like tun-
nels or large canyons. The ventila-
tion on a still day can be negligi-
ble. It is advisable to avoid wal-
king through this area unless a
respirator is used.
Unfortunately, this is where the differential pressure gauges for each
compartment are located. Because it is necessary to observe the pressure
drop for each compartment during the filtering mode and during cleaning, an
inspector could spend a considerable amount of time in this area.
If there are any symptoms of problems, the inspector may need to look
into (not go into) one of the compartments. To do this the plant personnel
must isolate the compartment and then open the hatch. Since almost all
dampers leak, this can result in some flow of pollutant laden gas into the
walkway area. The inspector must have the appropriate respirator for the
type of particulate matter and gas present. If the flow of gas out the
hatch is too rapid, shut the hatch immediately.
SLIDE 6-21
This is a close-up view of a walk-
way between compartments of a large
baghouse. This particular unit is
under negative pressure. Therefore,
there is less risk from accumulated
pollutants and oxygen deficiency.
Nevertheless, all areas with poor
natural ventilation should be ap-
proached cautiously.
93
-------
SLIDE 6-22
The fan shown in the slide serves a
large venturi scrubber. It is below
the scrubber and surrounded on three
sides by building walls. The static
pressure of the duct leading from
the fan to the stack is under a low,
but nevertheless significant, posi-
tive pressure. A gap in the isola-
tion sleeve or a hole in this duct
could result in high concentrations
of the pollutants contained in the
gas stream escaping to the
inspector's breathing level.
All fan houses or partially enclosed
areas surrounding fans must be ap-
proached cautiously.
SLIDE 6-23
This is a close-up photograph of the
isolation sleeve on the discharge
side of the fan shown in the slide
above. There are a number of gaps
wrhich are leaking high velocity gas
into the area around the fan.
94
-------
SLIDE 6-24
This is the scrubber control cab-
inet which is located less than 3
feet from the the cracked isolation
sleeve (see last two slides). An
inspector trying to determine the
operating conditions of the scrubber
could be fumigated with toxic or
oxygen deficient gases.
SLIDE 6-25
This is another isolation sleeve of
a fan. One half of the sleeve has
been removed for reasons that are
not known. A similar condition can
result in extremely high levels of
gases in the area around the fan.
This type of condition is not as
uncommon as it should be.
95
-------
SLIDE 6-26
This is the discharge side of a fan
downstream of a baghouse. A cloth
has been stretched over the fan dis-
charge presumably to reducethe
amount of the solids from accumulat-
ing around the fan. The area imme-
diately surrounding the fan had A to
12 inches of accumulation. It is
not unusual to find high emissions
from the discharge of a control
system baghouse. What is unusual is
the futile effort to keep the mate-
rial in the fan.
This slide illustrates that high
levels of pollutants can exist near
fans which discharge into poorly
ventilated areas.
SLIDE 6-27
A continuous emission monitor mounted
on a stack of a coal-fired utility
boiler is shown in this slide. The
unit is between the stack liner and
the outer shell. The cylinders with
calibration gas are stored just out
of view to the left. If these cylin-
ders leak, it is possible to have
undesirable concentrations of sulfur
dioxide and nitrogen oxides in the
area around the transmissometer.
Transmissometers mounted on positive
pressure ducts can have high pollu-
tant levels around the unit due to
fugitive leaks.
96
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SLIDE 6-28
Source: EPA Air Pollution
Training Institute
This is a drawing of a floating roof
storage tank for hydrocarbons. High
concentrations of organic vapors can
exist on the top of the roof because
of leaks through the seals. The
vapor concentration should be meas-
ured before the inspector enters to
check the seals.
The external walls of the tank block
off the wind resulting in poor ven-
tilation on the roof surface. The
highest concentrations of organic
vapors occur in precisely the areas
that the inspectors check the seal
condition.
SLIDE 6-29
This is a photograph of a building
demolition site. While attempting
to get samples of the insulation
material in the area, the inspector
could enter a sheltered area where
there is a high concentration of
asbestos fibers.
In addition to the obvious inhala-
tion hazards there are a number of
physical hazards. These include
floors which can not support the in-
spector's weight and falling bricks.
97
-------
SLIDE 6-30
This is a view of the inside of a
fabric filter. A REGULATORY AGENCY
INSPECTOR SHOULD NEVER ENTER AN AIR
POLLUTION CONTROL DEVICE. FATAL
INJURIES ARE POSSIBLE INSIDE THESE
DEVICES.
These devices should be entered only
by individuals trained and equipped
for confined area entry. They must
be specifically trained and equipped
to survive the potential hazards
inside air pollution control
devices. These hazards include but
are not limited to:
1, Asphyxiants
2. Toxic Gases
3. Toxic Particulate
A. Hot, Free Flowing Solids
5. Oxygen Deficiency
6. High Voltage
7. Rotating Equipment
It is more difficult to rescue an individual overcome inside an air
pollution control device than it is to rescue persons from sewers and other
equally dangerous locations. This is because most units have very small
hatches, many internal components that could snag rescue ropes, and most
devices are located in high and remote parts of the plants.
A QUALIFIED AGENCY INSPECTOR CAN EFFECTIVELY ACCOMPLISH ALL OF THE
INSPECTION REQUIREMENTS WITHOUT ENTERING THE CONTROL DEVICE. INSPECTORS
SHOULD REFUSE TO ENTER ANY COLLECTOR EVEN WHEN ENCOURAGED TO DO SO BY PLANT
PERSONNEL. PLANT PERSONNEL SHOULD ABSOLUTELY REFUSE PERMISSION FOR THE
INSPECTOR TO ENTER THE CONTROL DEVICE.
When an inspector is overcome inside a collector it is probable that
one or more of the plant personnel will attempt a rescue. This places
these individuals at a very substantial risk.
This issue is stressed because the author has noted a wide spread lack
of respect for the hazards inside these collectors despite the accident and
"near miss" history. Some manuals even imply that internal inspections
should be done routinely. Others place great faith in the conditions of
the collectors. These individuals do not suspect that the isolation
dampers on many collectors leak severely, rendering an "isolated" compart-
ment as dangerous as a compartment which is on line. Some people also
place too much faith in the lock out systems of the collectors. For all of
these reasons there is a need to stress the potential hazards that exist
inside air pollution control devices. REGULATORY AGENCY INSPECTORS NEED
NOT AND SHOULD NOT ENTER THESE DEVICES.
98
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SLIDE 6-31
Recognizing areas that are potential
sites for exposure has been the
first topic presented in this lec-
ture because avoiding hazards is the
best way to minimize risk. Many of
the materials inhaled during the
inspection have poor warning proper-
MOST CONTAMINANTS ties. In other words, the person
HAVE raay nave no physical sensation that
POOR WARNING PROPERTIES thei? ar.e hi§h levels of pollutants
in the air.
For example, the inhalation of dust
and fume rarely causes any immediate
physical discomfort or impairment.
For this reason it is possible for
undesirable quantities of toxic mat-
erials such as lead, arsenic and as-
bestos to reach the lungs where they
can be slowly absorbed by the blood
and attack organs such as the liver
and kidney.
The chemical and physical asphyxiants are another group of chemicals
with very poor warning characteristics. Chemical asphyxiants such as car-
bon monoxide and hydrogen sulfide can occur at life threatening levels
without any odor or taste perception. The most common physical asphyxi-
ant, carbon dioxide, also does not have any odor.
Most organic compounds and nitrogen dioxide are not very soluble and
can penetrate deep into the lower lung. The initial symptoms of exposure
are non-specific and may not be recognized by the inspector who is preoccu-
pied in conversation with plant personnel or in the inspection activities.
These symptoms include dizziness, drowsiness, headache, light-headedness,
and nausea. Acute exposure can result in pulmonary edema hours after the
exposure.
The chemicals which have the best warning properties are those which
are partially soluble in body fluids. The low taste and odor thesholds of
compounds such as sulfur dioxide, ammonia and chlorine are due primarily to
the solubility of these materials. Most individuals (but not all) will
Quickly leave an area with a high concentration of such chemicals. Failure
to do so, however, can lead to severe cardio-pulmonary problems.
Inspectors should review the plant files to determine which chemicals
might be encountered during the inspection. The warning properties of
these materials should be reviewed so that everyone is aware of the con-
sequences of exposure to the toxic materials. One very useful document to
assist the inspectors is the NIOSH/OSHA Pocket Guide to Chemical Hazards.
"The field manual is available from the Superintendent of Documents, U.S.
Government Printing Office, Washington D.C. 20402. Each inspector should
have a copy of this document and any other reference materials necessary
the types of chemicals which may be encountered.
99
-------
BERYLLIUM
Route of Entry — Inhalation of Dust and Fume
Symptoms — Intense, Brief Exposure May Result in
Nonproductive Cough, Low Grade Fever,
Chest Pains, and Shortness of Breath
Consequences — Acute Exposure Can Result in Chemical
Pneumonia with Pulmonary Edema Several
Hours After Exposure
SLIDE 6-32
The next series of slides discusses
several of the common chemicals
which can exist in the partially
confined areas and surrounding areas
of air pollution control systems.
This section demonstrates the im-
portance of the use of respirators
and avoidance of unnecessary expos-
ures to the chemicals.
The warning properties and possible
effects of beryllium are listed in
this slide. This is one of the most
toxic chemicals which may be inhaled
by a field inspector. Like a number
of other materials, this can cause
edema several hours after exposure.
The initial symptoms of exposure are
not very dramatic.
Due to the poor warning properties of beryllium and the very serious
consequences of exposure, field inspectors must plan to use personal pro-
tective equipment. They should not wait for the initial symptoms of
exposure to this material. All areas of potential exposure should be
discussed with the plant personnel before the inspection and all areas
which are not relevant to the inspection should be avoided.
SLIDE 6-33
Route of Entry
Symptoms
CADMIUM
— Inhalation of Dust and Fume
— Acute Exposure May Occur Without
Immediate Symptoms
Consequences — Pulmonary Edema
Cadmium is another toxic part-
iculate material with little in the
way of initial warning symptoms.
The consequences of an acute expos-
ure include a very serious respira-
tory condition.
100
-------
SLIDE 6-34
Route of Entry
Symptoms
HYDROGEN SULFIDE
— Inhalation of Gas
— At High Concentrations There Is No Odor
Consequences — Chemical Pneumonia May Develop Several
Hours After Exposure
At low concentrations, hydrogen sul-
fide is an eye irritant and it has a
very disagreeable rotten eggs type
odor. If these symptoms are noted,
the inspector should leave the
affected area of the plant. Ex-
posure to higher concentrations of
hydrogen sulfide can occur in areas
close to the point where these symp-
toms were first noted. At moderate
to high concentrations, hydrogen
sulfide is an extremely deadly
chemical: at high concentrations the
gas quickly overcomes the olfactory
senses.
It is possible to walk into a confined or partially confined area with
toxic concentrations of hydrogen sulfide and be only briefly aware of its
presence before olfactory fatigue overcomes your senses and you think the
problem has gone away. Brief exposure to such conditions can lead to
pulmonary edema and other serious respiratory problems in 6 to 12 hours
after the exposure. The exposure can also result in immediate death.
A large number of the industrial processes frequently inspected by
regulatory agencies handle high concentrations of this gas. These include
sour gas wells, petroleum refineries, and petrochemical chemical plants.
It can also be found in some unlikely locations such as downstream of cup-
olas. Pockets of the chemical can occur in partially confined areas around
the sources and it can even occur in depressions along the ground.
SLIDE 6-35
Route of Entry
Symptoms
NITROGEN OXIDES
— Inhalation of Gas
— Irtttial Symptoms Include Cough, Chills,
Fever. Headache, Nausea
Consequences — Acute Pulmonary Edema May Follow Five
to TWelve Hours After Exposure
During the exposure to nitrogen
oxides only mild bronchial irrita-
tion may be experienced. Concentra-
tions of 100-150 ppm are dangerous
for periods of 30 to 60 minutes.
Nitrogen oxides are generated in al-
most all combustion processes. While
they do not have a distinctive odor
it is sometimes possible to see the
orange color of nitrogen dioxide.
Also, nitrogen oxides are often accompanied by sulfur dioxide which
can be smelled and tasted at low levels. When there is the odor of sulfur
dioxide it is the possible that nitrogen dioxide is present. Unfortunate-
ly nitrogen oxides can occur without the odor of sulfur dioxide.
This set of gases is one example of the nonsoluble chemicals. The
site of attack is the deep lung and the consequences of acute exposure is
aevere. Typical effluent concentrations are 400 to 1000 ppm. Concentra-
tions of 100 to 150 ppm are possible in partially confined areas.
101
-------
SLIDE 6-36
Route of Entry
Symptoms
Consequences
ASBESTOS
Inhalation of Fibers
No Immediate Physical Symptoms
Asbestos is a Confirmed Carcinogen
Asbestos is a confirmed carcinogen.
Exposure to asbestos fibers can
occur while inspecting building de-
molition sites. There are no imme-
diate physical symptoms following
the exposure to asbestos.
This is one of the best publicized
of the known or suspected carcinogen
compounds. Other chemicals commonly
encountered include vinyl chloride,
benzene, and halogenated organics.
SLIDE 6-37
CHLORINE
Route of Entry — Inhalation
Symptoms — Intense Irritation of Eyes, Nose, and Throat
Consequences — Respiratory Problems
Chlorine is one of a number of chem-
icals which are partially soluble in
mucous membranes. The initial site
of attack includes the eyes, nose,
and throat. It has relatively good
warning properties.
Exposure can occur due to an acci-
dental release from process equip-
ment. Inspectors must be aware of
plant warning sirens and know what
to do if a cloud of chlorine is ap-
proaching their location.
The possibility of chlorine release is just one of the reasons why it
is important that plant personnel accompany the inspector at all times. As
soon as there is a warning siren indicating a release in the general vicin-
ity, everyone should proceed to a safe area and check in by phone to a cen-
tral location. The wind socks or pennants flying from the tops of some
process equipment provide a general indication of the wind direction*
Obviously, it is usually safest in the upwind direction of the suspected
release area. An area engulfed by the charactristic yellow cloud should be
avoided while going to a protected area. Respirators should be carried
while inspecting areas where chlorine releases are a significant
possibility.
102
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SLIDE 6-38
DETECTION AND MEASUREMENT
OF
INHALATION HAZARDS
There are many methods and instru-
ments currently available for the
detection and measurement of inhala-
tion hazards. For the inspector's
purposes, any method or instrument
used should be relatively inexpen-
sive, lightweight and easy to trans-
port. It should also be simple to
use.
SLIDE 6-39
• Personal Protection Badges
• Detector Tubes
• Combustible Gas Indiators
Keeping the above fact in mind, this
discussion will center on three ways
of detecting and/or measuring air
contaminants: personal protection
badges, detector tubes, and combust-
ible gas analyzers.
The personal protection badges are
useful mainly to warn the inspector
that he has encountered a high con-
centration of the applicable gas.
The detector tubes can be employed
for both detection and fairly ac-
curate measurement of most types of
pollutants.
The combustible gas analyzers are used to measure the explosion
potential of vapors and thus are useful for detecting and measuring a
number of volatile organic compounds.
103
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SLIDE 6-40
PERSONAL PROTECTION
BADGES
The commercially available personal
protection badges function by two
different mechanisms. One type
gives a comparatively instant indi-
cation of the presence of the appro-
priate gas by undergoing a change in
the color. The other is worn for a
specified amount of time (e.g. 8-hour
shift and then is sent to a lab
where it is analyzed for adsorption
of the pollutant). The second type
is much like the radiation badges
with which you may be familiar.
We'll discuss only the first type at
length, because this type is most
useful for the inspector for instan-
taneous detection of inhalation
hazards.
SLIDE 6-41
Leak-Tec
VMrtWVtt* - * »«*
:
* «
This type of passive dosimeter or
personal protection indicator is a
badge which has a piece of reagent
impregnated filter paper (or button
in the case of CO badges) which
chemically reacts with the specified
gas causing the indicator to change
color. The color change provides a
warning of excessive exposure to a
toxic gas.
104
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SLIDE 6-42
INSTANT READING BADGES AVAILABLE
Toxic Substance Critical Cone. Color Change
Ammonia 25ppm Yellow to Blue
Carbon Monoxide SOppm Tan to Black
Chlorine 1ppm White to Yellow
Hydrazine 1ppm White to Yellow
Hydrogen Sulfide 5ppm White to Brown
Nitrogen Dioxide ippm White to Yellow
Ozone 1ppm White to Brown
The types of badges available from
one manufacturer are listed in this
slide along with the critical con-
centration of the specific gas which
affects the color change. The crit-
ical concentration is based on the
time-weighted average (TWA) for 8
hours of exposure to the gas. In-
spectors can clip these badges to
their belts to warn them if high
concentrations of these gases are
present.
SLIDE 6-43
In theory, the degree of color
change of these badges can be
correlated with a particular concen-
tration of the gas over time. This
is shown in this slide of the manu-
facturer's color chart for the am-
monia badge. The manufacturer, how-
ever, no longer supplies these
charts, but it is useful to note
that the degree of color change can
be used to estimate the relative
concentration of the gas. Of course,
any change to blue on this badge
would signal the wearer to leave the
area immediately.
These badges accumulate very low concentrations of gas over time. For
example: if a chlorine badge is exposed to 0.2 ppm for several days, a
color change will eventually result due to the total concentration of
chlorine exposure. This may result in the false conclusion that a 1 ppm of
high concentration of chlorine was present in the ambient air during the
of the color change. As a result of this accumulation characteristic
the badges, it is recommended that inspection personnel use the badges
one time.
105
-------
SLIDE 6-44
BADGE BLOCKING GASES
Ammonia High Concentration of acid
gases such as: Sulfur Dioxide
Nitrogen Dioxide
Hydrogen Sulfide
Carbon High Concentrations of
Monoxide Nitrogen Dioxide temporarily
block reaction.
Temp<0°C
Chlorine High Concentration of Carbon
Monoxide, Hydrogen Sulfide
& Hydrazine
Hydrazine Ammonia
Hydrogen No known gases or vapors
Sulfide block the reaction
Nitrogen High Concentrations of
Dioxide Hydrogen Sulfide, Carbon
Monoxide & Hydrazine
Ozone High Concentrations of
Hydrogen Sulfide, Carbon
Monoxide & Hydrazine
Before making use of these badges,
it is essential to understand their
limitations. As this slide shows,
all the types of badges except
hydrogen sulfide have certain gases
which "block" or prevent the color
change reaction.
SLIDE 6-45
GAS
INTERFERENCES
REPEAT-
ABILITY
Ammonia Amines & other basic 90%
gases or vapors
Carbon Hydrogen Sulfide 90%
Monoxide Tobacco Smoke
Ammonia Turns Indicator
Blue
Chlorine Hydrogen Chloride 95%
Ozone. Nitrogen Dioxide
Hydrazine Primary Amines 90%
Hydrogen Gases & vapors contain- 90%
Sulfide ing reduced sulfur such as
Mercaptan. Gases con-
taining phosphorous
Nitrogen Chlorine, Ozone 95%
Dioxide Hydrogen Chloride
Ozone Hydrogen Chloride 95%
Nitrogen Dioxide
Chlorine
The reagents on each type of badge
which affect the color change for
the gas of interest are sensitive to
one or more other gases. This is
termed interference and a list of
interfering gases for each badge is
shown in this slide.
Also shown in this slide is the
repeatability for each type of
badge.
106
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SLIDE 6-46
EFFECTS OF WATER
Water is necessary for the color
change reaction; badge deteriorates
after 3 to 5 days exposure to the
atmosphere
Sensitivity of reaction increases with
increase in humidity
Water has quite a significant effect
on the indicators. Their sensitiv-
ity increases as the humidity.
Dry atmospheres also affect the
badges response. The color changes
that the badges undergo require the
presence of water. When an indica-
tor is exposed to the ambient atmos-
phere, water that is present in the
paper begins to evaporate; the rate
is dependent on the temperature and
the humidity. As it evaporates, it
removes some of the the color change
reagents along with it.
Eventually a critical point is reached where the amount of water and
reagent remaining is insufficient to cause a color change. This point
usually occurs with 3 to 5 days of exposure to the atmosphere. Carbon mon-
oxide badges are an exception to this because they use a different type of
indicator material.
SLIDE 6-47
OTHER CONSIDERATIONS
• Temperature Range — 50° to 120°F
• SneifLife— Six months
• storage — Cool, dry place away
from direct sunlight
• Reusable— No
Other important considerations are
listed on this slide. It is clear
that the badges are not as reliable
under cold conditions. The shelf
life should be carefully watched.
Dispose of expired badges. Storage
during the six months should be in a
cool, dry place away from direct
sunlight.
Some of the indicators (chlorine,
nitrogen dioxide, ammonia, and ozone
appear to "regenerate" when removed
from the contaminated environment.
Badges that have gone through a
distinct color change due to
exposure should not be reused even
if it has"regenerated" to the orig-
inal color. When a color change
occurs a portion of the reagents are
used and thus the level of sensitiv-
ity probably decreases.
107
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SLIDE 6-48
GAS INDICATOR OR
DETECTOR TUBES
Gas indicator or detector tubes of-
fer a more sophisticated system for
detection and measurement of gases
and vapors than the personal protec-
tion indicators discussed in the
last set of slides.
SLIDE 6-49
Detector tubes provide a general
indication of concentration for more
than 150 gases, vapors, and a few
aerosols.
Source: National Draeger, Inc.
108
-------
SLIDE 6-50
Although detector tubes are used in
a variety of applications, the air
pollution inspector is most likely
to employ them for two different
purposes. The first is the measure-
ment of pollutants for monitoring
purposes. This slide shows a mea-
surement being taken to investigate
a possible leak from process equip-
ment.
Source: National Draeger, Inc,
SLIDE 6-51
The second use of detector tubes is
the sampling of potentially
hazardous atmospheres in confined
areas, partially confined areas, and
in areas around positive pressure
duct systems. Sampling information
can then be used to make decisions
concerning entry to the area and
selection of proper respiratory pro-
tection.
Source: National Draeger, Inc,
109
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SLIDE 6-52
DETECTOR TUBE SYSTEM
• Pump
Bellows
Piston
• Indicator Tube
The detector tube system consists of
two parts, the pump (usually bellows
or piston) and the indicator tube
(appropriate for whatever gas or
vapor is being sampled).
SLIDE 6-53
The pump is used to draw a measured
volume of the air to be sampled
through the indicator tube. In the
case of the bellows pump shown in
the slide, a fixed and constant
volume of air is drawn through the
tube each time the bellows are
squeezed. To sample the measured
volume of air appropriate for a
certain indicator tube, the pump is
squeezed the number of timoc speci-
fied in the literature for each type
of tube.
Source: National Draeger, Inc.
110
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SLIDE 6-54
The indicator tube is a hermetically
sealed glass tube (the ends are
broken off immediately prior to use)
containing a solid granular material
impregnated with an agent which
reacts to a specific air contaminant
as it is drawn through the tube.
Source: National Draeger, Inc,
SLIDE 6-55
TYPES OF INDICATOR TUBES
1. Direct Reading Stainlength
2. Color Comparison
3. Color Matching
Based on the method used to
interpret the gas concentration,
there are three major types of
indicator tubes. The first is the
stainlength tube where the length of
a colored stain indicates the
concentration of the contaminant;
this used either a set number of
pump volumes or you count the number
of pump volumes to produce a set
stainlength.
Ill
-------
SLIDE 6-
«»»**»**<*«*
,«••*
-------
SLIDE 6-58
INSTRUMENT LIMITATIONS
As was true with the personal
protection indicators, it is
important to understand the
limitations of the instruments.
A critical limitation is the quality
control exercised by the
manufacturer of the indicator tubes
and pumps. NIOSH currently conducts
a certification program designed to
help insure that detector tube
sampling systems. conform with
established performance specifica-
tions. The manufacturer's submit
test batches of tubes for certifica-
tion and at the same time must
submit a quality control plan for
the manufacture of the same. A
manufacturer's tubes are certified
by specific type; the certification
includes use with the pump unit.
SLIDE 6-59
ACCURACY
• Certification indicates ± 25%
• Tube calibration can be user verified
• Pump should be calibrated with
respect to volume and flow rata
The NIOSH certification on a type of
indicator tube signifies that if
they are used according to manufact-
urer's directions, they will produce
readings that are within plus or
minus 25% of the true concentration
at 1,2, and 5 times the test stand-
ard (usually the TLV).
Their accuracy can be verified by
sampling a contaminant source of
known concentration prodecures for
this are described in several of the
references.
The pump itself can and should be user calibrated at regular intervals
with respect to both volume (delivered) and flow rate. Several references
also describe procedures for this.
113
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SLIDE 6-60
OTHER CONSIDERATIONS IN THE USE OF
DETECTOR TUBES
and
• Shelf life and storage
• Interfering gases
• Color comparison and matching accuracy
• Non-interchangeability of different manufacturers' tubes
and pumps
Other .Limitations which must be
considered are listed in this slide.
Extremely high or low temperatures
will affect measurement accuracy.
This is due to its influence on both
the volume of air sampled and the
kinetics of the reaction occuring in
the detector tube.
SLIDE 6-61
TEMPERATURE EFFECTS ON
INDICATOR TUBE SHELF LIFE
°F Shelf Life
75
120
175
210
255
300
2 years
1 year
weeks
1 week
3 days
1day
Temperature also greatly influences
the shelf life of detector tubes.
Under normal conditions the shelf of
most tubes is 2 years. But as is
shown in this slide, storage at
elevated temperatures can greatly
decrease the shelf life. Thus, it
is important that the tubes be
carefully stored to insure a
reasonable temperature; they should
never be left in a place such as the
trunk of the inspector's car.
Refridgeration, in fact, can
increase shelf life, but the tubes
must be temperature equilibrated
before use. Tubes should also not
be stored in direct sunlight.
-------
SLIDE 6-62
OTHER CONSIDERATIONS IN THE USE OF
DETECTOR TUBES
• Temperature effects on pump volume and reagent re-
action kinetics
• Shelf life and storage
• Interfering gases
• Color comparison and matching accuracy
• Non-interchangeability of different manufacturers' tubes
and pumps
Similar to the personal protection
badges, many of the detector tubes
are not totally specific for one
contaminant and there are
interfering gases and vapors which
must be considered. These
interferences can be negative be
additive and are usually noted in
the manufacturer's literature.
There can also be problems with the
color comparison or matching aspect
of reading the tubes. Different
lighting can change the look of a
color chart or color standard. The
color matching charts themselves can
fade with time and color blindness
will obviously hinder comparisons.
Finally, indicator tubes and pumps
from different manufacturer's should
never be interchanged because of
differences in pump suction proper-
ties and flow rates.
115
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SLIDE 6-f>3
COMBUSTIBLE GAS INDICATOR
(SNIFFER)
A combustible gas indicator is used
to detect and/or measure combustible
gases and vapors in the atmosphere.
This section covers one type of com-
bustible gas indicator, the "snif-
fer", which used catalytic combustion
to measure and read out in percent
of the Lower Explosive Limit (LEL)
for the gas being tested.
SLIDE 6-64
For the agency inspector, this in-
strument has basically the same type
of uses as the detector tubes except
that it detects only combustible
gases and does not measure low con-
centrtion levels as well.
It can be used effectively for sim-
pie screening of combustible VOC
leak sources. This slide shows an
inspector sampling at a bulk gaso-
line terminal using the Century OVA
a more sophisticated combustible
gas analyzer than we will discuss.
The "sniffer" can be used for test-
ing confined, partially confined,
and any other suspicious area for
the presence of combustible gases.
116
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SLIDE 6-65
This is a photograph of a combust-
ible gas indicator. It uses the
catalytic combustion principle of
operation. The squeeze bulb on the
right draws an atmospheric sample
(mixture of air and combustible gas)
into the sample chamber. Here it is
brought into contact with a hot
platinum wire (filament) where rapid
oxidation of the gas with the oxygen
in the air occurs. This raises the
temperature of the wire causing an
increase in its electrical resist-
ance. The change in resistance
activates the readout meter.
The instrument is designed so an increase in the amount of combustible
gas causes a proportional increase in the resistance of the platinum
filament and thus the amount of combustible gas present is directly
indicated on the meter.
The instrument also has another chamber which houses a "reference"
filament. This compensates for the variable condition under which it must
operate, e.g., minor voltage fluctuations and changes in temperature.
SLIDE 6-66
PREOPERATIONAL CHECK
1 • Zero mechanically
2. Turn on/Zero
3. Purge
* Apply known calibration gas
5. Check for appropriate meter response based on gas
calibration curve
6 Punje
7. Turn off
This slide summarizes the preoper-
ational check (or simple one point
calibration) of the instrument shown
above. Other combustible gas indica-
tors of similiar sophistication will
use comparable procedures.
The meter is mechanically zeroed
using the screw at the center bottom
of the meter. The unit is then
turned on and the meter rezeroed
electrically using the on/off knob.
To purge, squeeze the aspirator bulb
several times.
A calibration gas of known concentration is applied to the inlet
Opposite the aspirator bulb connection) and the bulb is squeezed three to
^°ur times. Calibration gases can be obtained in cylinders, made using a
&as calibration kit, or made using methods described in a number of the
Deferences listed in the Appendix. The instrument response is then checked
^ased on the appropriate gas calibration curve. Finally, the unit is
Purged again and then turned off until ready for use.
117
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SLIDE 6-67
58
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The unit readout scale in in per-
cent of the LEL from 0% to 100%.
The LEL is the leanest mixture of a
gas which will burn (or explode)
when ignited. This gives an instant
indication of danger of explosion
of an atmosphere, it does not in-
dicate whether or not it is
dangerous with regard to toxicity.
Also, when a gas sample concentra-
tion exceeds the LEL, the meter
pointer generally first deflects
rapidly upscale and then toward or
below zero.
The instrument is factory calibrated on hexane. When used to sample
other gases it will read slightly higher or lower depending upon the gas.
An example of this is shown in this slide which is the gas curve for
methane. A methane gas concentration at 40% of the LEL (or 20% methance)
will read 60% on the meter of a unit calibrated on hexane. Two percent
methane-in-air is a commonly used calibration gas and should based on the
proceeding discussion give the response of 60% on the meter. Other gases
can be used for calibration using the appropriate gas curve (usually avail"
able with the unit) .
Similarily, these curves can be used to roughly estimate the
concentration in ppm of a known gas in the atmosphere, by first converting
the meter reading in %LEL to %LEL of the known gas using the curve, and
then converting the %LEL of the gas to a percent-in-air using this formula*
(%LEL of gas) x (LEL of gas) = % Gas-in-air
The percent gas-in-air figure is then converted to ppm by
ten thousand.
multiplying
118
-------
SLIDE 6-68
OPERATION
1. Purge
2. Turn on/Electrically zero
3. Sample atmosphere
4. Note response on meter
5. Purge
6. Turn off
For routine operation of the
unit the steps listed in this slide
are followed. It should first be
purged by squeezing the aspirator
bulb several times. Then it is
turned on and electrically zeroed
using the on/off knob.
Then it is ready to be used to
sample the atmosphere in question.
This is accomplished by inserting
the hose or probe into the area to
be tested and squeezing the bulb
several times (Allow A squeezes for
a standard 5 foot sampling hose,
increase by 3 squeezes for each ad-
ditional 5 feet). Note the reading
on the meter when the needle
stabilizes for a few moments after
the last bulb squeeze. After taking
the reading, purge the unit in fresh
air until the needle returns to zero
and then turn it off.
SLIDE 6-69
COMBUSTIBLE GAS INDICATOR
LIMITATIONS
Because there are so many types of
combustible gas indicators, each
with slightly different limitations,
the following section will only
cover the general limitations of
combustible gas indicators. Before
using any instrument of this type,
the inspector should carefully read
all the manufacturer's literature
and take note of the specific con-
siderations for its use.
The slides that follow will outline
items which should be considered
with every instrument and should
give the agency inspector a good
idea of what to be aware of in using
such an instrument.
119
-------
SLIDE 6-70
INTRINSIC SAFETY CONSIDERATIONS
• Check instrument approval
• Repair work that breaches intrinsic safety warrants re-
certification
Combustible gas analyzers use heated
wires, electronics, flames and other
sources of ignition. When they are
immersed in a test atmosphere, it is
theoretically possible that they
could ignite an explosion. Con-
sequently, most combustible gas
analyzers are constructed such that
ignition is highly improbable in
certain atmospheres. These in in-
struments are then considered "in-
trinsically safe" for use in these
atmospheres. Each instrument should
be checked to determine for what
types of atmospheres it is certified
or approved.
It is also important to consult the operating and service manual
before troubleshooting or servicing so that the intrinsic safety built
into the detector will be maintained. If any repair work breaches the
intrinsic safety of the instrument, it should be returned to the
manufacturer for testing and recertification.
SLIDE 6-71
LIMITATIONS OF SUITABILITY FOR
CERTAIN GASES OR ATMOSPHERES
• Hatogenated hydrocarbons cause filament poisoning
• Condensible vapors cause fouling
• Oxygen enriched atmosphere may cause flash back
• Oxygen depleted atmospheres will cause a much
decreased Instrument response
Certain gases and/or atmospheres can
cause instrument damage, explosion,
or inaccurate response. Halogenated
hydrocarbon gases or vapors produce
thermal decomposition products which
corrode the sensor and alter its
sensivity and integrity. Condensible
vapors foul the sensor.
In spite of the flame-arresting
system, some instruments may flash
back in a pure oxygen or oxygen-
enriched atmposhere. Check the
instruction for instrument limita-
tions PRIOR to use.
Oxygen depleted atmospheres pose a different sort of problem.
Instrument response is almost always dependent on the presence of suffici-
ent oxygen to support combustion. Without it, meter operation ie erratic
or the respons for the combustible gas is less than the actual concentra-
tion. If an oxygen depleted atmosphere is suspected, detector tubes can be
used to make that determination, before using the combustible gas indica-
tor. Other atmosphere-related limitations not listed in this slide include
(1) a decreased response to sulfur compounds such as hydrogen sulfide, (2)
no response to explosive dust atmospheres, and, as mentioned previously,
(3) an erratic response to gas-enriched atmospheres.
120
-------
SLIDE 6-72
OTHER CONSIDERATIONS
Sensitivity to Gas
Calibration Gas
Zero Drift
Temperature
Dust and High Humidity
Probe Length
Position Sensitivity
lnt*rchang«abiltty of Parts
All instruments exhibit "zero
drift", i.e. they drift from "true
zero" as the instrument is used.
Thus frequent checks of the zero, in
a CLEAN atmosphere are important.
Temperature will affect instrument
sensitivity and accuracy. The
LEL of most gases varies with the
temperature. NO instrument should
be used at extremes of temperature
unless the temperature's effect is
knownn. Dust and humidity also have
an effect; therefore, many models
include a dust filter and drying
agent.
When a long sampling line or probe is needed in the field, the
instrument should be calibrated using the same set up. In the case of the
unit shown in Slide 6-65 the user must remember to increase the bulb
squeezes in proportion to the line length. This unit is also position
sensitive; it must always be kept upright while sampling.
As is true with the detector tube systems, NEVER
from one type of combustible gas indicator to another.
interchange parts
SLIDE 6-73
•i
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Finally, the user must take into
account the identity of the gas he
or she is measuring and the
instrument's sensitivity to that
gas. It must be remembered that the
instrument is calibrated on only one
gas at a time and it will measure
only that gas accurately. This
slide shows that a unit calibrat-
ed with hexane will read slightly
lower when sampling hydrogen. Inter-
fering gases and vapors can also
change the readings.
The sensitivity of the particular instrument must also be considered
when measuring low concentrations of toxic gases, because many instruments
are not accurate at the lower end of the scale.
121
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Source: National Safety Council
SLIDF. 6-74
The next portion of the lecture
concerns the selection and use of
respirators. This is something that
must be addressed before starting
the inspection.
There is a lot more to the use of a
respirator than just slapping one on
when the need arises. Each person
should have a medical examination to
confirm that he or she can manage
the additional stress caused by the
respirator. Inspectors should be
trained on the use and fitting of
each style of respirator they will
use. The training should also in-
clude instructions concerning regu-
lar cleaning and inspection of the
unit. There should be written pro-
cedures covering all aspects of res-
pirator selection and use.
This lecture will provide only a brief introduction to this topic. A
complete program concerning respirator selection and use requires one half
to three days, depending on the types of units to be used. All U.S.
Environmental Protection Agency personnel engaged in field activites are
required to have a minimum of 6 hours training on the selection and use of
respirators (see EPA Order 1440.3, July 24, 1981). It is also necessary to
have follow-up training of two to four hours after the initial training
program.
For U.S. EPA personnel, the selection of the appropriate respirator
must be based on the assessment of the hazards and the Decision Logic Table
specified in EPA Order 1440.3. The inspector's preliminary assessment of
the potentially hazardous conditions should be discussed with plant person-
nel before starting any inspection. In the selection of the respirators,
it may also be beneficial to read the three references listed below, copies
of which will be made available during the training program.
1. Respiratory Protection Program Guideline, U.S. Environmental
Protection Agency, Draft Dated February 1983.
2. NIOSH/OSHA Pocket Guide to Chemical Hazards, U.S. Department
of Health And Human Services of the U.S. Public Health Ser-
vice and the U.S. Department of Labor, Dated September 1978.
Available from the Superintendent of Documents, U.S. Govern-
ment Printing Office, Washington, D.C. 20402
3. Respiratory Protection, A Manual and Guideline, Prepared by
L.R. Birkner, Celanese Corporation and Published by the
American Industrial Hygiene Association, Dated 1980
122
-------
SLIDE 6-75
REQUIREMENTS CONCERNING
USE OF RESPIRATORS
These are the minimum requirements
for a respirator program which meets
the specifications outlined in OSHA
Standard 1910.134.
1. Written standard operating pro-
cedures governing the selection and
use of respirators shall be estab-
lished.
2. Respirators shall be selected on
the basis of hazards to which the
worker is exposed.
3. The user shall be instructed and
trained in the proper use of respir-
ators and their limitations.
4. Where practicable, the respirators should be assigned to
workers for their exclusive use.
individual
5. Respirators shall be regularly cleaned and disinfected. Those issued
for the exclusinve use of one worker should be cleaned after each day's
use, or more often if necessary. Those used by more than one worker shall
be thoroughly cleaned and disinfected after each use.
6. Respirators shall be stored in a convenient, clean, and sanitary loca-
tion.
7. Respirators used routinely shall be inspected during cleaning. Worn or
deteriorated parts shall be replaced. Respirators for emergency use such
as self-contained devices shall be thoroughly inspected at least once a
month and after each use.
8. Appropriate surveillance of work area conditions and degree of employee
exposure or stress shall be maintained.
9. There shall be regular inspection and evaluation to
continued effectiveness of the program.
determine the
10. Persons should not be assigned to tasks requiring use of respirators
unless it has been determined that they are physically able to perform the
work and use the equipment. A local physician shall determine what health
and physical conditions are pertinent. The respirator user's medical
status should be reviewed periodically (for instance, annually).
H. Approved or accepted respirators shall be used when they are
available. The respirator furnished shall provide adequate respiratory
Protection against the particular hazard for which it is designed in
accordance with standards estiablished by competent authorities. (portion
of this paragraph has been omitted, the reader is referred to the OSHA
Standard.)
123
-------
SLIDE 6-76
The
SELECTION CRITERIA
• Concentration of Contaminants
• Forms of Contaminants
• Oxygen Levels
• Size and Shape of Head
respirators must be selected
based on a number of factors, some
of which are listed on this slide.
One of the most important factors is
the concentration of the material.
The respirator must satisfactorily
perform at these concentrations. It
is also important to know if the
concentration is Immediately Danger-
ous to Life and Health (IDLH) and/
or if the concentration is close to
the explosive range.
Unfortunately, the concentration of the contaminant or contaminants
is rarely known because the exposures are due to accidential and/or inter-
mittent conditions. Also, the inspector visits many individual sites
around the control system during the performance evaluation. Rarely is
there monitoring data available for all of these locations.
It is very important to know what the oxygen level is at the various
locations to be visited. Many air pollution control systems handle gas
streams with very low oxygen levels of 3 to 6%. Even some small leaks can
lead to localized oxygen concentrations below 19.5%, the point at which
oxygen deficiency becomes a problem.
The warning properties of the materials must also be known. This is
best done by the file review before starting the inspection. If some of
the chemicals are irritants, a full face piece unit may be required,regard-
less of the concentration. If the chemical(s) can be absorbed through the
skin, protective clothing may be necessary in addition to a respirator.
The form of the material (gas, vapor, fume, dust, etc.) must be known
to the extent possible. This is a verdifficult question, however, since
the form of the contaminant can change after release to the ambient air
surrounding the control device. In most cases, the low ambient temperature
condenses vaporous material to form very small particle size aerosols. In
some cases, the materials released can react very rapidly with sunlight or
with available oxygen to form more toxic compounds than were in the duct
originally. It is also possible for one material released around pollu-
tion control equipment to react with another to form very undesirable
materials. Atmospheric ammonia can participate in some of these reactions.
For all of these reasons, the determination of the form of the material is
difficult. It ±s hard even to determine what combination of chemicals is
present at a given time. Due to these problems it is advisable to avoid
areas of potential exposure if at all possible. This is why so much
attention was given to the recognition of potential exposure sites during
the early portion of this lecture.
Another factor which must be considered in the selection of a respir-
ator is the size and shape of the individuals head. There are usually
several models of each type available, and the unit chosen must be comfort-
able and fit tightly.
124
-------
SLIDE 6-77
This slide shows a typical logic
used to decide what type of respira-
tor is necessary. The decision is
based on the form and concentration
of the contaminant(s) and the level
of oxygen.
Inspectors on routine duties should
not enter areas which are known to
be immediately dangerous to life and
health. Alternative means should be
sought to determine the compliance
status of a facility with such con-
ditions. Inspectors should also not
enter areas which are known to have
less than 19.5% oxygen.
Regulatory agency inspectors rarely have the training necessary to
wear air line respirators, hose mask type respirators, self-contained
rebreathers, or the combination breathing apparatus. Areas where such
equipment is necessary must be avoided.
The most common types of respirators available to field inspectors
include (1) dust and mist masks, (2) dust, mist and fume masks, chemical
cartridge respirators with special filters, and (3) gas masks with special
filters. These will be discussed in more detail in the following slides.
Information on other types of respirators is available in the publications
listed earlier.
SLIDE 6-78
This is a close-up photograph of a
dust and mist respirator. This is
the minimum protection necessary for
exposure to particulate matter. Nor-
mally, it is sufficient for mate-
rials having a permissible exposure
limit (PEL) of greater than 0.05
mg/m3 or 2 mmpcf. It is limited to
material concentrations which are
less than 10 times the PEL. This
type of respirator must never be
used when the oxygen content is less
than 19.5% or the concentration of
the contaminant is approaching the
level which is immediately dangerous
to life and health (IDLH).
To be of any benefit, the mask must be fitted properly. Beards, side
burns, and moustaches can prevent a good fit. This type of respirator
should be discarded whenever the resistance to breathing increases, the
unit is damaged, and after completing the inspection at a specific plant.
They should not be used when gaseous or vapor phase pollutants are possible
in the breathing area.
125
-------
SLIDE 6-79
The maximum allowable concentrations
MAXIMUM ^or Us:"-n8 the dust and mist masks
are relatively low. To illustrate
ALLOWABLE this, take the Permissible Exposure
CONCENTRATION Limit specified in the NIOSH/OSHA
Pocket Guide and multiply by a num-
ber not greater than 10. Compare
the result with the concentration of
the material in the duct, stack, or
control device. In most cases, the
the gas stream levels are one hun-
dred to one thousand times the maxi-
mum allowable levels indicated for
dust/mist mask use. Even a small
gas stream leak into the partially
confined areas around the equipment
could lead to excessive levels.
The dust/mist mask is an acceptable respirator when only particulate
is in the air and when it is possible to avoid partially confined areas or
parts of the plant downstream of heavy fugitive emissions such as those
shown in this slide.
SLIDE 6-80
This is a dust, mist and fume type
mask. It is appropriate for short
term exposures to very low mass con-
centrations of particulate matter.
and when there is the possibility of
exposure to metallic fume or any
aerosol or condensed vapors.
Like any mechanical filter, this
mask does not supply oxygen and
should not be used if oxygen the
level is less than 19.5%. These
masks are not effective for gases
and vapors.
All processes which operate at elevated temperature can conceivably
generate fumes. The condensation of vaporous material causes small parti-
cle size material to form. Some of the materials commonly encountered by
field inspectors include arsenic trioxide, mercury and lead oxide.
If the contaminant(s) are irritants it will be necessary to use a full
face mask respirator rather than the unit shown.
126
-------
SLIDE 6-81
CHEMICAL CARTRIDGES CANNOT BE USED
FOR THESE MATERIALS
Aniline Nickel Carbonyl
Arsine Ozone
Carbon Monoxide Phosgene
Hydrogen Fluoride Vinyl Chloride
Hydrogen Sulflde
This is a half mask type chemical
cartridge respirator. It can be
fitted with a number of different
styles of cartridges depending on
the gases, vapors and/or particulate
matter in the breathing zone.
As a general rule, the half masks
can be used when concentrations of
hazardous pollutants are 10 times
the Permissible Exposure Limit or a
concentration of 1000 ppm, whichever
is lower. The full face mask can
usually be used when the concentra-
tion is 100 times the Permissible
Exposure Limit or 1000 ppm, which-
ever is lower. Neither mask should
ever be used when the concentrations
are Immediately Dangerous to Life
and Health. This figure is often
less than the maximum allowable
concentration calculated by multi-
plying the PEL by 10 or 100.
This type of respirator does not supply oxygen, therefore it can not
be used in the oxygen concentration is less than 19.5% If the materials
are irritants, the full mask type of respirator must be used.
SLIDE 6-82
This is a partial list of the
materials which cannot be well hand-
led by chemical cartridge respi-
rators.
Some of these materials cannot be
adsorbed in the cartridge and some
have such poor warning properties
that it is difficult to determine
when the respirator is no longer
performing adequately.
Unfortunately, the list includes a
number of very common chemicals.
127
-------
SLIDE 6-83
Source: National Safety Council
This is a photograph of a gas mask.
These masks are equipped with a full
face mask and a canister for removal
of contaminants. They can be used
at higher concentrations than the
chemical cartridge units. The chin
type canisters are usually accep-
table for concentrations up to 5000
ppm and the industrial size canis-
ter can often be used up to 20,000
ppm. There are canisters available
which remove acid gases, organic
vapors, ammonia, carbon monoxide,
and several other materials.
This respirator does not supply oxygen, therefore, it cannot be used
when the oxygen concentration is less than 19.5%. Also, it should not be
used for entry into atmospheres known to be Immediately Dangerous to Life
and Health.
This type of respirator is moderately uncomfortable. The amount of
time that it is worn should be minimized. This should not be a problem for
field inspectors because most areas visited do not have high enough concen-
trations to require this type of unit. The inspector should not be in
areas of high concentration.
Some of the problems associated with this unit include fogging of the
face plate and difficulty in the mounting of glasses. These units should
be cleaned and disinfected after each use and inspected regularly to ensure
that they will work properly.
SLIDE 6-84
Spring
%Carbon monoxide catalyst
..
Organic vapor adsorbent
This is a cross sectional view of a
canister. The average life of a
canister at the upper concentration
limit is in the range of only 20 to
30 minutes.
After use, the canister should be
destroyed to prevent accidential re-
use. An old canister should never
be used. It is much better not to
do the inspection than to go into a
potentially contaminated area with
an exhausted canister.
Check valve
128
-------
SLIDE 6-85
Source: National Safety Council
This is a self-contained breathing
apparatus (SCBA). It is required
when there is a suspected oxygen
deficiency, when there are high con-
centrations of known pollutants, and
when there are significant levels of
unknown contaminants.
There are three basic types: (1) The
demand or pressure demand open cir-
cuit systems, (2) self generating
closed circuit devices, and (3)
liquid or compressed oxygen, closed
circuit (rebreathing) devices.
Very detailed unit-specific training is necessary be fore an indivi-
dual should use a SCBA. The training should include instruction in fitting
the face plate, and regular cleaning and inspection of the component parts.
Only those units which operate with a positive pressure in the face
Plate should be used in contaminant concentrations which are potentially
Immediately Dangerous to Life and Health. All SCBAs, if they are in good
condition and are used properly, can provide protection for atmospheres
having less than 19.5% oxygen.
Most regulatory agencies can not afford this style of respirator.
Usually only personnel assigned to especially hazardous duty (such as
hazardous dump site investigation, and emergency response) have this equip-
•nent. Normally, the air pollution control inspector is not involved in
such duties, therefore, he or she will not usually have SCBAs available.
This means that areas where SCBAs might be necessary must be avoided.
SLIDE 6-86
All respirators used by inspectors
should be checked for tightness
prior to entering the contaminated
area. In the case of the chemical
cartridge and gas mask type units,
there are several qualitative tests
which can be done in the field. The
tests are listed in this slide.
The negative pressure the inlet of
the cartridge or canister is blocked
and the wearer inhales gently. The
face plate should collapse slightly
and there should be not obvious in-
leakage. The test itself can result
in a respirator not fitting properly
any longer, therefore, this provides
only a very rough check of the fit.
129
-------
SLIDE 6-87
This is a continuation of the qual-
~....._.,..,-.-._,-~». atitive means to check the fit of
QUALITATIVE FIT TESTS cartridge and gas mask type units.
• Banana Oil
• IrritantSmoke The positive pressure test is very
similar to the negative pressure
test. The exhaust valve is blocked
for a short period of time. If a
slight positive pressure can be
maintained without any obvious leak-
age then there is a rough indication
that the respirator seals properly.
This test also can disturb the fit
of the respirator.
The isoamyl acetate vapor test is conducted by inserting a cartridge
or canister which removes organic vapor into the respirator. The flask
containing isoamyl acetate, material which has a strong scent of banana
oil, is waved in the general vicinity of the individual wearing the respi-
rator. If the individual can smell the vapor, then the respirator must be
refitted. The problems with this test are individual variability in re-
sponse to the odor and the olfactory fatigue which can result from several
unsuccessful attempts to seal the respirator.
Another qualitative test involves the use of an irritant smoke. This
should be done only in an area with good ventilation by a trained person.
This test is less prone than the isoamyl acetate vapor test to the subjec-
tivity of the individual wearing the respirator.
130
-------
SLIDE 7-1
PROBLEMS OF
BIOLOGICAL HAZARDS
This is an area of plant inspection
safety that is not often discussed,
but should be given consideration by
the agency inspector. Hence, the
next several slides will briefly out-
line the potential biological hazards
in conducting plant inspections.
7-2
TYPES OF BIOLOGICAL HAZARDS
* Viruses
* Bacteria
* Fungi
This slide lists the major categories
of biological hazards. The first two,
bacteria and viruses, are hazardous
because of the potential of some kinds
to infect humans and cause disease.
The third, fungi, such as molds and
spores, are hazardous because of the
intrinsic toxins in some varieties
and their potential to cause lung
problems upon inhalation. The routes
of entry for biological hazards tend
to be Inhalation, ingestion, and eye
contact. Contact with the skin, ex-
cept (1) in the case of a cut or
other opening or (2) transfer to the
mouth does not tend to be as much of
a problem.
131
-------
SLIDE 7-3
Here is one example of a commonly
encountered potential biological ha-
zard. This inspector is attempting
to obtain a scrubber liquor sample.
Since it is possible that the liquor
might contain bacteria, the inspector
should avoid contamination of his skin
and clothing. It would be preferable
to sample from a valve, but when sam-
pling the liquor from a valve he would
then have to be careful not to splash
the liquor.
SOURCES WITH POTENTIAL
BIOLOGICAL HAZARDS
• Municipal Incinerators
• Pathological Incinerators
* Foodstuff Processors
SLIDE 7-4 This is a partial listing of indus-
tries and source types that may have
potential biological hazards. In the
case of municipal incinerators, the
inspector should simply avoid contact
with the refuse and refuse handling
equipment.
Pathological ^incinerators are used to
dispose of refuse from hospitals, in-
fectious disease laboratories, and
other research facilities. This ref-
use can contain potentially infectious
material. Once again, the inspector
should avoid coming in contact with
any of the material and in this case,
he might consider respiratory protec-
tion if he must spend any time near
the refuse.
Agricultural operations may potentially have biological hazards because
foodstuffs are an excellent medium for fungal and bacterial growth. One
example of this is molds growing on the grain in grain elevators. One mold
in particular, aspergillus, that grows on grain contains the very harmful
toxin, aflatoxin.
Some inspectors have expressed concern over inspecting genetic engineer-
ing firms. The organisms used by these firms to clone genes and make the
product are always of a variety which does not survive in anything but con-
trolled laboratory conditions. Thus, there is probably no risk to the inspec-
tor from these organisms.
Regarding personal protection against biological hazards, the first re-
commendation is to avoid the hazards (e.g. sampling scrubbber liquor without
allowing skin or eye contact). As a precaution against inhalation of air-
borne fungi and bacteria, a disposable dust mask can be worn. Eye protection
should be worn in situations where splashing of contaminated water is possible;
and, of course, one should take care to avoid rubbing the eyes at ANY time*
A practical recommendation for followup to all inspections is removal and
washing of clothes and washing of the body.
132
-------
SLIDE 7-5
PROBLEMS OF CHEMICALS
WHICH
ABSORB THROUGH THE SKIN
Although probably not one of the most
significant air inspection safety prob-
lems, the inspector should at least
be aware of the potential for chemical
hazards to the skin.
SLIDE 7-6
ROUTES OF CHEMICAL EXPOSURE
* Inhalation
* Ingestion
* Skin Absorption
* Skin or Eye Contact
Toxic chemicals can enter the body by
various routes. The most important
route of exposure is inhalation which
was discussed at length previously.
Ingestion is another route of chemi-
cal exposure. It is not usually the
cause of industrial exposures. It
can usually be effectively controlled
by never eating or smoking with con
taminated hands or in contaminated
areas.
After inhalation, skin or eye contact
and skin absorption are the next most
common industrial exposure routes.
Skin contact with many chemicals,
even with no absorbtion, can cause
primary irritation (such as that from
many acids, alkalis, and organic
solvents) and resulting skin damage
or dermatitis.
In the case of skin absorption, the agent may penetrate and cause sensiti-
j tion to repeated exposures (like the catechols in poison ivy) or penetrate
:|J sufficient amounts to cause systemic poisoning (such as with significant
*tn exposure to phenols) . Chemical contamination of the eye can result in
degrees of eye irritation or in absorption and systemic poisoning.
133
-------
SLIDE 7-7
SKIN ABSORBABLE SUBSTANCES
Phenol
Nitrobenzol
Aniline Oil (and derivatives)
Carbon Tetrachloride
Turpentine
Nitroglycerine
Cresol
Hydrocyanic Acid
Benzene
Cyanides
Naphthalene
Xylene
Regarding skin exposure to chemicals,
the agency inspector has one advan-
tage over most plant personnel in
that he is less likely to undergo
chronic (repeated or prolonged) skin
exposure to one chemical. Thus, oc-
cupational dermatitis is not as much
of a problem. He must, however, still
deal with acute exposures to both the
primary irritants and the chemicals
which absorb through the skin.
General categories of chemicals that
should be suspected as primary irri-
tants and avoided include: inorganic
and organic acids, inorganic alkalis,
amines, metallic salts, and organic
solvents. A number of these irri-
tants produce their effect moments
after contact and obviously should be
immediately washed off using appro-
priate procedures.
Others may not show any effects for several hours or days. Thus, it is
important to avoid contact in the first place. The Pocket Guide to Chemical
Hazards (see Bibliography) indicates chemicals which are primary irritants
with the notation "Con" (meaning skin and/or eye contact) in the "Route" (of
entry) column. It also provides the appropriate first aid measures for chem-
ical skin contact and it describes appropriate personal sanitation procedures
(washing and changing of contaminated clothes) for over 380 chemicals.
This slide lists some of the more common chemicals which actually pene-
trate through the skin into the system and cause internal problems including
damage to the central nervous system and organs such as the liver. For ex-
ample, phenol is absorbed through the skin quite readily and exposure of a
large part of the body (as the result of a spill, etc.) can result in death.
The Pocket Guide also lists skin absorption hazards using "Abs" in the Route
column. It is recommended that the inspector, prior to visiting any facility
using large quantities of certain chemicals, check the entry in the handbook
for each chemical to assess its potential effect on the skin including route of
entry, first aid, and personal sanitation procedures.
134
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FACTORS INFLUENCING
SKIN ABSORPTION
Sustained, profuse sweating
Fat-dissolving agents
Friction
Amount of oils
Length of contact
Breaks in skin
Hyperemia
Age of skin
SLIDE 7-8 This last slide lists a number of the
factors which influence skin absorp-
tion. Profuse sweating can deprive
the skin of oils or increase friction
in some areas of the body, both of
which will facilitate absorption.
Agents which solubilize lipids (fats
in the skin) can penetrate the skin
themselves or create an opportunity
for other substances (that normally
would not have) to penetrate.
The amount of oil in the skin has an
affect on absorption; the more oils
the less absorption.
Length of contact with the substance is very significant. Hence the
importance of washing after possible contact and removing clothes that are,
or may be, contaminated.
Breaks in the skin obviously allow some chemicals to enter the body that
otherwise would not have and allows others to get in faster. Hyperemia, or
increased blood flow to the skin, also promotes absorption. And finally, the
younger the skin the greater the absorption of chemicals.
135
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136
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SLIDE 8-1
SAFETY CONSIDERATIONS
IN THE USE OF
PORTABLE INSTRUMENTS
It is important to recognize when
portable instruments are necessary
and when it is safe to use the in-
struments. This lecture concerns
some of the basic safety procedures
for portable instruments such as
static pressure gauges, pH meters,
thermocouples, and pitot tubes.
Prior to using any instruments in a
plant, the procedures to be follow-
ed should be discussed with plant
representatives
BATTERY POWERED EQUIPMENT
• ph Meters
• Thermocouples
• RashUghts
SLIDE 8-2
Some of the portable instruments are
battery powered. The most common
instruments with internal batteries
are digital thermocouples and pH
meters. These instruments should
not be taken through areas with
potentially explosive dusts or va-
pors. It is possible for them to
provide a source of ignition for the
explosive materials. Before taking
such instruments into a plant it is
necessary to get a hot work permit
from plant representatives. Only
instruments which are specified as
intriniscally safe for hazardous
locations can normally be used where
there are potentially explosive
dusts and/or vapors.
In the case of the pH meter, it is almost always possible to leave
the meter in a protected area and bring the liquor sample to it. Often,
the plant chemical laboratory is a convenient location to leave the pH
meter. A dial-type thermometer can be substituted for the digitial thermo-
couple if there is any question concerning the safety of the thermocouple.
The problems with battery powered instruments also apply to flash-
lights. Inspectors should use only explosion proof flashlights. The plant
representatives should confirm that the flashlights comply with plant
restrictions.
137
-------
SLIDE 8-3
Only the instruments necessary for
the inspection should be carried.
In trying to carry too much, it is
possible to have an accident while
walking through areas with obstacles
and while climbing.
Bulky items should not be carried in
pants pockets. This restricts the
natural climbing actions and makes
an accident more likely.
One convenient way to carry the
portable instruments is shown in
this slide. The side pouch allows
free movement of the legs and frees
the hands for climbing and support.
As discussed during lecture #2, this slide also shows one of the
limits of side pouches. Long items such as the dangling dial type thermo-
meter should not be carried. When it is necessary to get bulky items like
6 foot pitot tubes to elevated platforms, it is generally necessary to use
a rope.
SLIDE 8-4
HEROIC PORTS
Only measurement ports with safe
access should be used. NEVER MAKE
HEROIC EFFORTS TO USE A PORT WHICH
HAS BEEN IMPROPERLY LOCATED. Unfor-
tunately, a large number of such
measurement ports exist. The next
set of slides shows some of these
undesirable ports.
If there are no safe ports, the
preferred locations should be dis-
cussed so that plant personnel can
put in measurement ports prior to
the next inspection.
138
-------
SLIDE 8-5
A close-up view of a pulse jet bag-
house is shown in this slide. The
port on the inlet ("dirty") side of
the baghouse is shown in the center
of this slide. To reach the port it
would be necessary to reach over a
42 inch diameter inlet duct carrying
hot gas. It should also be noted
that inlet ductwork is on the edge
of the building roof, therefore, it
is impossible to stand in the area
between the ductwork and the fabric
filter.
The inlet port easily could have been placed at one or more locations
along the inlet ductwork. The value of the static pressure measured would
have been very similar to that measured at the port shown. The ports in
the inlet ductwork would have been both convenient and safe.
SLIDE 8-6
This is the same baghouse shown in
the previous slide. A slack tube
manometer is shown just to the right
of the caged access ladder. If one
of the two ports of this instrument
had plugged, it would be necessary
to disconnect the leads and rod out
the ports. Then the portable gauge
could be attached and the actual
static pressures measured. In this
case, however, it would be necessary
to lean out through the cage to
reach the ports. These ports should
not be used.
It is very common to find the situation depicted in this slide. In
some cases it would be necessary to climb up the outside of the cage to
reach the ports. THESE PORTS SHOULD NEVER BE USED! Ladders are for climb-
ing only and are not intended to be used as temporary sampling platforms or
gymnastic equipment.
139
-------
SLIDE «-/
In the dimly lit upper portions of
this tray type scrubber there are
two apparent measurement ports ac-
ross one of the trays. The only way
to reach these ports is to stand on
the top of the hand rails around the
access platform. DO NOT STAND ON
THE TOP OR MID RAILS OF ANY GUARD
RAIL. They are not intended for
this purpose and a very serious fall
is possible. Sometimes it is diffi-
cult to resist the temptation to
climb on the guard rail since some
plant personnel will occassionally
do this. Always resist this ap-
proach.
SLIDE 8-8
The measurement ports on this small
pulse jet collector are located on
side (right center of the slide).
There is a gap of approximately 3
feet between the collector and the
end of the roof. It is 40 feet to
the ground from this location. The
plant personnel may wish to reach
the ports by leaning a ladder from
the building roof (left portion of
slide) to the collector. This
should not be done. If the ladder
were to slip, a very serious acci-
dent could occur. Complicating this
particular situation was the fact
that the roof was slightly sloped
and was covered with moderately
slippery solids. In any case, a
portable ladder should not be used
to cross a chasm between the walking
surface and the collector.
140
-------
SLIDE 8-9
In many cases, the only ports which
are available are the 4 inch diamet-
er stack sampling ports. In some of
the smaller plants there may not be
a sampling platform around the
ports. As shown in this slide, it
is possible to reach the ports by
riding in the bucket of a front end
loader. THIS SHOULD NOT BE DONE.
The bucket is not intended to serve
as a temporary sampling platform and
the bottom is far from level when
the bucket is in the position shown.
A fall against the side of the
bucket could result in a serious
head injury.
The buckets generally contain at least a small quantity of solids
which can be quite slippery. Furthermore, the operator of the front end
loader could make a mistake and dump the inspector. A front end loader
should not be used as a sampling platform under any circumstances.
SLIDE 8-10
This is the inlet duct to a small
baghouse which operates at a high
gas temperature. The skin temper-
atures of both the collector side
wall and the flange to the right of
the measurement port are 320 °F.
While attempting to open the port, a
burn is likely. The port could have
easily been placed several feet up-
stream of the flange or on the side
wall of the collector and provided
the same data. This was the only
location where there was an unavoid-
able burn hazard.
Whenever working with hot ducts (most are hot), the inspector must be
very conscious of the access to the port and the general clearances around
the entire platform. It is easy to inadvertently leaning against a hot duct
wall while trying to stand up or while trying to move around a cluttered
platform area.
141
-------
SLIDE 8-11
m
The inspector shown in this slide is
about to suffer a burn on the hot
wall of this scrubber. This is on
the inlet portion of the unit, at a
location before the gas stream has
had an opportunity to cool. Gloves
should be worn and the dial type
thermometer should be held in the
manner shown.
SLIDE 8-12
itei &
! I
When selecting measurement ports,
choose the smallest one which allows
use of the various probes. The one
half inch port shown in the slide is
often an ideal size. The very large
4 inch diameter ports can allow
substantial flow of pollutant laden
gas into the breathing zone.
142
-------
SLIDE 8-13
Whenever instruments are used after
electrostatic precipitators it is
important to use a grounding/bonding
cable. It should be attached prior
to insertion of the probe or pitot
tube into the duct. The gas stream
passing the port contains has parti-
cles with a high static charge. The
static charge can accumulate to very
high static voltages on the probe or
pitot tube.
The shock suffered by the inspector
may not have a high enough current
to be fatal, but, it can surprise
the individual and result in a fall
off the platform. Also, the shock
can be quite painful.
It is also necessary to ground all probes when making measurements
within fiberglass ducts. The duct walls can accumulate a very high static
charge. As the probe is approaching the measurement port, a spark will
jump from the duct to the probe. This can be as painful and surprising as
the shocks suffered downstream of precipitators.
SLIDE 8-14
Static grounding/bonding cables
should be used whenever there is the
possibility that static will accumu-
late on the probe while it is in the
gas stream. This can happen when-
ever the particulate mass concentra-
tion is relatively high and the
relative humidity is low. Under
such conditions the static charge
probably can reach levels sufficient
to cause a spark over to the duct
wall (near the measurement port).
If the dust is explosive and there
is sufficient oxygen, then an explo-
sion will result.
It should be noted that this problem has not been reported and the
potential for an explosion is only speculation at this time. However, a
large majority of the gas streams at elevated temperature have too low a
relative humidity to allow dissipation of the static charge. Also, most
gas streams at the inlets of the air pollution control systems have a high
enough mass concentration to be in the explosive range. Some ducts also
contain deposits of solids which could be explosive. In some cases, there
is enough oxygen for an explosion. For all these reasons, there is the
potential for a major explosion due to the static charge. It should be
continuously drained off by using the grounding/bonding cables shown in
this slide.
143
-------
SLIDE 8-15
When using an oxygen and carbon di-
oxide analyzer of the type shown in
this slide, care is necessary to
prevent contact with the corrosive
absorbing solutions. There is a top
valve used for admitting the gas
sample. When absorbing the compon-
ents of the gas sample, the entire
instrument is inverted several times
to mix the gas with the absorbing
solution. This top valve must not
be depressed while inverting the
instrument because the corrosive
liquid will spill out.
If for any reason there is contact with the liquid, wash it off imme-
diately. The oxygen solution contains hydrochloric acid and the carbon
dioxide solution contains potassium hydroxide.
SLIDE 8-16
When obtaining a liquor sample for
pH measurement or other analysis,
contact with the liquor should be
avoided. The slide illustrates the
wrong way of acquiring a sample.
In some cases, the liquor contains
bacteria and viruses. Chemicals
which can be rapidly absorbed by the
skin may also be present.
144
-------
SLIDE 8-17
This is a port for a reverse air
baghouse operating at approximately
400 °F on a continuous basis. Hie
plug for this port will remain hot
as long as several hours after being
removed. Some people forget about
this problem and pick up the plug
with bare hands.
When withdrawing a probe or pitot
tube from a hot gas stream, gloves
should be used to hold the probe.
These probes can be at temperatures
ranging from 200 to 1200 °F.
SLIDE 8-18
While making fan rotational speed
measurements, care must be taken to
prevent entrapment between the belts
and the sheaves. A partially expos-
ed belt as shown in this slide must
be avoided. Only belt guards with a
small access port and good protec-
tion around the entire sheave and
belts should be used.
145
-------
SLIDE 8-19
When using a long probe such as a 6
to 8 foot pitot tube, all high volt-
age lines and tracks must be com-
pletely avoided. It is not uncommon
to have a high voltage line 10 to 15
feet above a collector or to have a
high voltage track within 10 feet of
a collector. As the pitot tube is
being withdrawn, it may approach one
of this and allow a spark to jump
the gap. This can result in a fatal
shock. Measurement ports in the
general vicinity of high voltage
lines must be avoided.
SLIDE 8-20
Many control devices operate at very
high negative static pressures. If
the measurement port is as large as
that shown on this slide, it is pos-
sible to lose the probe into the gas
stream. At the very best this would
be embarrassing. Under the worst
circumstances, this could damage the
fan downstream and result in the
disintegration of the fan. Ports of
this size should be avoided if at
all possible.
146
-------
SLIDE 8-21
SANDING DISK
COPPER TUBE
RUBBER STOPPER
-DUCT WALL
This slide illustrates one means to
prevent loss of the probe into the
high negative static pressure ducts.
This consists of a rubber stopper
(drilled to be slightly small) fol-
lowed by a. commercially available
sanding disk having a quarter inch
hole. The sanding disk must be at
least one inch larger in diameter
than the port being used. The rub-
ber stopper holds onto the quarter
inche O.D. probe and the sanding
disk holds onto the rubber stopper.
This assembly has been used up to a
static pressure of -120 inches of
water without any problems. The
main limit of this approach is that
The sanding disk can not be used for
very hot ducts.
SUMMARY
SLIDE 8-22
Since there are some additional
risks inherent in the use of any
portable instrument, they should
only be used when there is a defi-
nite need for the data. Use of the
instruments should be discussed with
plant representatives before the
inspection.
Only measurement ports with safe
access and adequate clearance for
high voltage lines should be used.
The potential for burns and/or ex-
posure to toxic gases should be kept
to a minimum.
The battery powered and line voltage instruments should not be taken
into areas where there are potentially explosive dusts and/or vapors. All
Probes used in ducts where there is the potential for static accumulation
should be bonded to a grounded duct. Suction of the probe into the gas
stream absolutely must be prevented.
147
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148
-------
SLIDE 9-1
AGENCY SAFETY PROGRAM
Any agency (or other organization)
whose personnel are involved in air
pollution control equipment inspec-
tion and/or maintenance should have
an organized safety program designed
to minimize the risk involved in these
operations. The U.S. Environmental
Protection Agency (EPA) has taken a
lead in this area in response to the
Occupational Safety and Health Act of
1970 and other government mandates
and has itself set up a very struc-
tured program.
This lecture outlines the elements
and goals which are basic to any
safety program of this type. It is
to every inspector's advantage to find
out about his employer's program (if
any) and to assist in instituting one
if there is none.
9-2
!• Written Safety Procedures (Guideline Manual)
*• Regular Safety Training
* Basic Protective Equipment
'• Medical Monitoring
This slide lists four basic elements
of a safety program. All field per-
sonnel should have access to a written
safety procedures guideline manual,
regular training in appropriate safe-
ty procedures, basic personal protec-
tion equipment for their duties, and
regular medical monitoring examina-
tions.
149
-------
SLIDE 9-3
SAFETY GUIDELINES MANUAL
Recognition of Hazards
Symptoms of Exposure
Safety Procedures for Hazards
Emergency Procedures
Use of Personal Protection Equipment
Reporting of Illnesses or Accidents
A written safety procedures manual
should be prepared by every regulato-
ry agency and private organization
involved in the inspection (or main-
tenance) of air pollution control
equipment. This manual should out-
line the agency's or organization's
policy concerning safety and at a
minimum address recognition of per-
tinent hazards, recognition of symp-
toms of exposure, safety procedures
to be followed for each type of ha-
zard, emergency procedures, use of
personal protection equipment, and
the reporting of illnesses or acci-
dents.
It is recommended that this manual be dated and revised whenever neces-
sary. All personnel covered by these guidelines should be responsible for
reading them carefully and for effecting needed modifications.
SLIDE 9-4
SAFETY TRAINING
Safety Procedures
Use of Personal Protection Equipment
CPR and First Aid
All field personnel should also par-
ticipate in a mandatory program of
safety training. This training pro-
gram would include instruction in re-
cognition of potential hazards, ap-
propriate safety procedures, and pro-
per use of personal protection equip-
ment. A judicious program would also
include instruction in Cardio Pulmo-
nary Resuscitation (CPR) and basic
First Aid.
This training should be regularly
scheduled; at least once a year I8
suggested. New employees assigned
field duties should receive this
training PRIOR to beginning field
work. Training programs should t>e
carefully tailored to the duties of
the individuals instructed; for ex-
ample, an air inspector assigned the
additional responsibility of respond-
ing to hazardous chemical spiH8
should receive considerably more
safety training than one assigned
only to investigate odor complaints*
150
-------
SLIDE 9-5
BASIC PROTECTIVE EQUIPMENT
Hardhat
Safety Shoes (steel-toed)
Safety Glasses and Goggles
Ear Protection
Dust, Mist, and Fume Masks
Cartridge-type Respirators
Agencies and organizations should
also provide their field employees
with personal protection equipment
suited to their duties. This slide
lists the basic protective equipment
recommended for Inspectors of air
pollution control equipment.
SLIDE 9-6
MEDICAL MONITORING PROGRAM
BASEUNE EXAMINATION
1. Medical and Occupational History
2. Physical Examination
3. Chest X-ray
4. Selected Blood and Urine Tests
5. Hearing
6. Lung Function
7. Other Special Tests
ANNUAL MONITORING EXAMINATION
This slide outlines the components of
a suggested medical monitoring pro-
gram. A medical monitoring program
should be designed to assess the
health status of individuals prior to
work, monitor for evidence of post-
work adverse effects, and evaluate
and treat work-related injuries and
illnesses.
Individuals should undergo the base-
line examination prior to doing any
field work to evaluate their suita-
bility for hazardous assignments and
capability for proper use of the nec-
essary personal protective equipment
and to establish baseline or refer-
ence data for comparison with find-
ings of future examinations.
The baseline examination usually consists of a detailed medical and oc-
cupational history, a thorough physical examination, and a number of specific
tests including a chest x-ray, blood and urine tests, an electrocardiogram, a
hearing test, lung function tests, and any other tests indicated by knowledge
of the work to be performed.
The annual monitoring examination then provides a way to detect work-
related adverse health effects and a reassessment of an individual's continued
fitness for assigned duties. It can also provide occupational health guidance
and data for occupational health studies. The annual examination usually
includes a history update; selected blood, urine, and pulmonary function
tests; and a screening physical exam.
151
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152
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APPENDIX A
BIBLIOGRAPHY
153
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154
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Accident Prevention Manual for Industrial Operations, National Safety
Council, 6th Edition, 1971.
A. M. Best Company. Best's Safety Directory. Volumes I and II. Oldwick,
NJ. 1984. (Published annually)
American Industrial Hygiene Association. Direct Reading Colorimetric
Indicator Tubes Manual, First Edition. Akron, Ohio. 1976.
American Industrial Hygiene Association. Manual of Recommended Practice
for Combustible Gas Indicators and Portable, Direct Reading Hydrocarbon
Detectors, First Edition. Akron, Ohio. 1980.
Birkner, L. R. Respiratory Protection: A Manual and Guideline, First
Edition. B. J. Held and B. E. Held (ed.). American Industrial Hygiene
Association, Akron, Ohio. 1980.
Brief, R. S. Basic Industrial Hygiene: A Training Manual. Prepared for
the Exxon Corporation. American Industrial Hygiene Association, Akron,
Ohio. 1975.
Burgess, W. A. Recognition of Health Hazards in Industry. John Wiley
and Sons, New York. 1981.
Bonney, T. B., et al. Industrial Noise Manual. American Industrial
Hygiene Association, Akron, Ohio. 1975.
Drager Corporation. Drager Gas Detector Tube Handbook, Fifth Edition.
Pittsburgh, Pa. February 1983.
General Industry Standards Part 1910. OSHA Publication 2206. U.S.
Department of Labor, Occupational Safety and Health Administration.
U.S. Government Printing Office, Washington, D.C. 20402. March 8, 1983.
Hirschfelder, D. Contact Lenses in the Workplace. Sightsaving, Vol 52,
(1): 14-18. 1983.
The Industrial Environment - Its Evaluation and Control, U.S. Department
of Health, Education and Welfare, 1973.
Macklnson, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (editors)
NIOSH/OSHA: Pocket Guide to Chemical Hazards. U.S. Dept. of Labor,
Occupational Safety and Health Administration; U.S. Department of Health
and Human Services: Public Health Services, Centers for Disease Control,
National Institute for Occupational Safety and Health. U.S. Government
Printing Office, Washington, DC. 20402. September 1978.
Occupational Diseases, A Guide to Their Recognition, Revised Edition.
U.S. Department of Health, Education and Welfare. June 1977.
Patty's Industrial Hygiene and Toxicology, Third Revised Edition, Volume 1.
G. Clayton and F. Clayton, Editors. Wiley-Interscience Publication Page 340.
155
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A Primer on Confined Area Entry. Rexnord, Safety Products. Malvern, PA.
Safety Manual for Hazardous Waste Site Investigation, U.S. Environmental
Protection Agency. Available from the Office of Occupational Health and
Safety, Waterside Mall, 401 M Street S.W., Washington, D.C. Draft Manual
dated September 1979.
Sax, N. I. Dangerous Properties of Industrial Materials, Van Nostrand
Reinhold Company, New York, N.Y.
Schwope, A. D., P. 0. Costas, J. 0. Jackson and D. J. Weitzman. Guidelines
for the Selection of Chemical Protective Clothing, A. D. Little, Inc. for
U.S. EPA. American Conference of Governmental Hygiensts, Inc. Cincinnati,
Ohio. 1983.
Stack Sampling Safety Manual, Prepared by Norman V. Steere & Associates
for the U.S. Environmental Protection Agency. September 1978.
United Technologies/Bacharach Instruments. Operation and Maintenance:
Model "L" Sniffer. Pittsburgh, Pa. 1981.
U.S. Environmental Protection Agency Field Health and Safety Program.
Prepared by Norman V. Steere and Associates, Inc., November 1982 for U.S.
EPA.
156
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APPENDIX B
REVIEW QUESTIONS
157
-------
158
-------
1. Cartridge type respirators are usually rated at .
a. concentrations twice on TLV
b. concentrations five times the TLV
c. concentrations ten times the TLV
d. concentrations fifty times the TLV
2. The use of hearing protection in high noise areas hinders normal com-
munication.
a. true
b. false
3. Common "partially" confined areas include .
a* walkways between large control systems
b. weather enclosures around hoppers
c. weather enclosures around precipitator roofs
d. pump houses
e. fan houses
f. mountings for continuous emission monitors
g. all of the above
A. "Partially" confined areas are particularlly dangerous when
a. the ducts or control equipment operate at positive pressure
b. the gas streams contain asphyxiants and toxic agents
c. the gas streams contain dusts and fumes
d. all of the above
5. Before inserting a probe Into a gas stream it is important to check
a. that the grounding cable Is in good physical condition
b. that the ground clamp does not interfere with the probe
c. that the clamp has penetrated any paint or corrosion layer
on the ground
d, all of the above
6. Ionizing radiation may be a problem around
a. electrostatic precipitator rappers
b. continuous emission monitors
c. damaged hopper level monitors
d. electrostatic precipitator electrical cabinets
159
-------
7. Falls may be caused by
a. slippery surface around wet scrubbers
b« climbing ice covered ladders
c. crossing roofs with heavy accumulations of snow or solids
d. protruding equipment in dimly lit areas
e. a and c
f. a and d
g. all of the above
8. Prior to using a respirator, an inspector should
a. be trained in the selection and use of respirators
b. be trained in the maintenance of respirators
c. have a physical examination
d. all of the above
9. When selecting what personal safety equipment is necessary during an
inspection, an inspector should be guided by •
a. what the plant representative and other plant personnel are
using
b. plant policies
c. agency policies
d. common sense
10. Exposure to particulate and gaseous contaminants often may result
a. downwash of effluent from short stacks
b. fugitive leaks from ducts and hatches into partially
confined areas
c* fugitive leaks through open static pressure taps
d. fugitive leaks around process equipment
e. all of the above
11. Safety shoes should be worn
a. only when required by plant policies
b. only when required by agency policies
c. for all plant inspections
d. when specifically required for plant entry
12. An inspector should not work alone during an inspection, unless
a. plant personnel are too busy to accompany the inspector
b. the inspector is very familiar with the plant
c. no entry into partially confined or confined areas is
anticipated
d. the Inspector has all the necessary personal protection
equipment
e. none of the above
160
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13. Burns may be caused by
a. contact with hot gas ducts
b. contact with measurement probes, such as pitot tubes
c. radiation from process equipment
d. high pressure steam leaks
14. High noise levels are frequently found near
a. fans
b. screw conveyors
c. electrostatic precipitator rappers
d. process equipment such as compressors and
grinding mills
e. rotary discharge valves
f. steam vents
15. The suspension of the hard hat needs to be checked at least
a. once a day
b. once a week
c. once a month
d. once a year
e. never
16. Most gaseous contaminants have good "warning properties" therefore the
inspector is usually aware that they are present .
a. true
b. false
17. The routes of entry of toxic compounds include
a. the eyes
b. the respiratory system
c. the skin
d. ingestlon
e. all of the above
18. Hazards of opening access hatches include:
a. asphyxiation due to free flowing solids found in hoppers
b. positive pressure systems creating force on the interior
of hatch
c. control device fires
d. burns from hot solids
e. hand injuries from "breaking the seal" of hatch
in negative pressure system
19. Contact lenses should not be worn during inspections
a. true
b. false
161
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20. Respirator or gas mask cartridges and canister air purifying capabili*
ties are identified by both worded labels and a color code. •
a. true
b. false
21. The use of a respirator exposes a worker to additional stress
a. true
b. false
22. The following symptoms may indicate exposure to air contaminants
a. headache
b. drowsiness
c. shortness of breath
d. neausea
e. loss of coordination
f. eye irritation
g. all of the above
h. none of the above
23. Static electricity is especially likely following .
a. a wet scrubber
b. a fabric filter collecting dry dust
c. electrostatic precipitation
d. mechanical collection
e. all of the above
24. Hearing protection is necessary whenever normal conversation cannot
be heard at a distance of feet.
a. 1
b. 2
c. 5
d. 10
25. Most types of hearing protection reduce noise intensity inn the 1000
to 4000 Hz range by .
a. 5 to 10 dB
b. 10 to 25 dB
c. 25 to 50 dB
d. 50 to 75 dB
26. Fan disintegration can be caused by
a. operating at excessive tip speeds
b. build-up of material ou the fan wheel
c. operating at high gas temperatures
d. erosion of the fan wheel
162
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27. At high concentrations hydrogen sulfide has odor.
a. a rotten eggs
b. a sewer
c. a fragrant
d. no
28. Ozone may be generated in .
a. fabric filter
b. an electrostatic precipitator
c. a wet scrubber
d. none of the above
29. Entry into the confined areas, of a fabric filter or electrostatic pre-
cipitator by an agency inspector should be done when
a. the equipment has been properly locked out
b. all components have been properly grounded
c. the sytem has been purged out and cooled
d. the interior environment ha been tested for oxygen and
gaseous contaminants
e. a properly trained individual is stationed outside to provide
assistance if necessary
f. none of the above
30. A self-contained rebreather is necessary whenever work is required
around areas which
a. have less than 19.5% oxygen
b. have gaseous concentrations that exceed the safe limit of
the cartridge and canister type respirators
c. have less than 16% oxygen
d. have less than 12% oxygen
e. have high carbon monixide levels
31. Access hatches should be opened
a. when the system is down and locked out
b. when the static pressure differential across the hatch
is approximately zero
c. by plant personnel only
32. The baseline inspection technique involves entry into the control
systems for internal inspection.
a. true
b. false
163
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33. If an Inspector experiences the nonspecific symptoms of exposure to
gases and vapors, he or she should
a. continue with the inspection until more definite symptoms
develop
b. discuss the potential exposure with plant personnel
c. leave the area immediately and reevaluate the conditions
d. all of the above
34. When climbing ladders, inspectors should keep their hands on the
a. side rails
b. foot rails
c. either
35. Which of the following symptoms may indicate exposure to air contaminants
a. drowsiness
b. shortness of breath
c. loss of coordination
d. eye irritation
e. light headedness
f. all of the above
36. During the inspection, the operator of a fabric filter compartment
serving a cupola states that the previous bag failure problem has
been corrected by using a new bag hanger design and by modifying the
tube sheet thimble. He suggests that you follow him into the fabric
filter compartment to confirm that this has been done properly.
What should the inspector do?
a. check all six compartments to ensure that the same modifications
were made in each
b. just check one or two compartments
c. limit the inspection to what can be seen from the access hatch
without going inside the compartments
d. review the drawings and do not waste time on the equipment
inspection
37. An internal inspection of an electrostatic precipitator should be con-
ducted by an agency inspector when .
a. there are indications on misaligned plates and wires based on the
secondary voltges and currents
b. there are indications of poor gas distribution and the source is
making major modifications to the precipitator inlet
c. there are symptoms of rapping reentrainment
d. the operator has reported severe corrosion problems
e. when hell freezes over
164
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38. A victim of heatstroke, the most severe heat-induced illness, will
have which of the following symptoms?
a. hot, dry skin
b. clammy skin
c. confusion
d. convulsions
e. all of the above
f. a, c and d
39. When should light clothing cover as much of the body as possible to
prevent heat stress?
a. when the temperature is greater than 100°F
b. when the temperature is less than 100°F
40. The single most effective way to prevent heat stress is:
a. wear appropriate clothing
b. avoid sources of heat
c. increase fluid intake
d. stay in good physical condition
41. If the plant personnel seem to be feeling fit, the inspector should
not worry about heat stress difficulties.
a* True
b. False
42. Environmental conditions which increase the likelihood that heat
stress will occur are:
a. steam clouds from control and process equipment
b. radiant heat from process equipment
c. excessive noise
d. all of the above
e. a and b
43. Passive dosimeters have certain characteristics which limit their
effectiveness. Some of these are:
a. They accumulate very low concentrations of gas over time and may
show a high concentration of gas when there is no danger.
b. They lose their effectiveness when exposed to the ambient air
for more than 3-5 days because the water in the indicator paper
evaporates.
c. The incidence of interference gases is higher the longer the
badge is worn.
44. Passive dosimeters can be reused because they "regenerate" after
being removed from the contaminated environment.
a. True
b. False
165
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45. Inspectors should cancel inspections if the wind chill factor is:
a. less than -40°F
b. less than -30°F
c. less than -20°F
46. Hypothermia and frostbite injuries can be prevented by:
a. layering clothing
b. staying dry
c. taking frequent breaks in warm areas
d. consuming warm food and/or beverages
47. The proper way to acclimate to cold stress is to observe the following
routine: Begin with an exposure period of 2 hours, Increase exposure
10 minutes per day for 5 consecutive days.
a. True
b. False
48. Frostbite should be treated by briskly rubbing the affected area with
snow.
a. True
b. False
49. Hypothermia victims may exhibit the following symptoms:
a. apathy and dlsorientation
b. uncontrollable shivering
c. decreased respiration
d. increased respiration
e. all of the above
f. a, b, and c
g. a, b, and d.
166
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Review Question Answers
1. c 22. g
2. b 23. fa,c
3. g 24. b
4. d 25. c
5. c 26. a,b,d
6. c 27. a
7. g 28. b
8. d 29. f
9. a,b,c,d 30. a,b,c,d,e
10. e 31. a,b,c
11. c 32. b
12. e 33. c
13. a,b,c,d 34. b
14. a,b,c,d,f 35. f
15. c 36. c
16. b 37. e
17. e 38. f
18. a,b,c,d,e 39. a
19. a 40. b
20. a 41. b
21. a 42. d
43. a,b
44. b
45. c
46. a,b,c,d
47. b
48. b
49. e
167
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168
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APPENDIX C
EXAMPLE OF ONE PLANT'S
SUBSTANCE EXPOSURE SYMPTOM CHART
169
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170
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SUBSTANCE
QVEREXPQSURE SYMPTOMS
ACETIC ACID
ACETONE
AMMONIA
ASBESTOS
BARIUM (SOLUBLE COMPOUNDS)
BENZENE
BROMINE
2-BUTANONE (MEK>
CALCIUM OXIDE
CARBON BLACK
CARBON DIOXIDE
CARBON DISULFIDE
CARBON MONOXIDE
CARBON TETRACHLORIDE
CHLORINE
CHLOROBENZENE
-------
(CONT'D)
-2-
SUBSTANCE
QVEREXPQSURF SYMPTOMS
CHLOROFORM
(TRICHLOROMETHANE)
CHROMIC ACID AND CHROMATES
CHROMIUM, SOL, CHROMIC, CHROMOUS
SALTS AS CR
COAL DUST (RESPIRABLE
FRACTION LESS THAN 52 S^)
COAL TAR PITCH VOLATILES
(BENZENE SOLUBLE FRACTION)
COPPER FUME
COPPER DUSTS AND MISTS
CYANIDE
DICHLORODIFLUOROMETHANE
(FREON-12)
DIPHENYL
ETHYL ALCOHOL
ETHYL ETHER
FLUOROTRICHLOROMETHAHE
(FREON-11)
GRAPHITE (NATURAL)
HEPTANE
HEXACHLOROETHANE
SUSPECT CARCINOGEN/CUMULATIVE
LIVER AND KIDNEY DAMAGE/NARCOSIS
SUSPECT CARCINOGEN/CUMULATIVE
LUNG DAMAGE/NASAL PERFORATION,
ULCERATION
CUMULATIVE LUNG DAMAGE/DERMATITIS
PNEUMOCONIOSIS
SUSPECT CARCINOGEN/CUMULATIVE
LUNG CHANGES
MODERATE IRRITATION EYE, NOSE,
THROAT, LUNG
MILD IRRITATION EYE, NOSE,
THROAT, SKIN
MARKED IRRITATION SKIM, EYE, NCSE
AND THROAT
DIZZINESS,' TREMORS, UNCONSCIOUS;
CARDIAC ARRHYTHMIAS, CARDIAC ARREST
MODERATE IRRITATION EYE, NOSE,
THROAT, BRONCHI, LUNGS
MILD IRRITATION EYE, NOSE,
THROAT/NARCOSIS
NARCOSIS/MILD IRRITATION EYE,
NOSE, THROAT
ACUTE CENTRAL NERVOUS SYSTEM
EFFECTS
CUMULATIVE LUNG DAMAGE
(PNEUKOCONIOSIS)
MODERATE IRRITATION EYE, NOSE,
LUNGS/CENTRAL NERVOUS SYSTEM
EFFECTS/NARCOSIS
CUMULATIVE ORGAN DAMAGE/CENTRAL
NERVOUS SYSTEM EFFECTS
172
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-3-
(CONT'D)
SUBSTANCE
QYEREXP OSURE_SYMPIQMS
HYDROGEN CHLORIDE
HYDROGEN SULFIDE
IODINE
IRON OXIDE FUME
ISOPROPYL ALCOHOL
LEAD FUMES AND DUST
L,P,G, (LIQUEFIED PETROLEUM GAS)
MERCURY (INORGANIC)
METHYL ALCOHOL (METHANOL)
METHYL CHLOROFORM
METHYLENE CHLORIDE
METHYL MERCAPTAN
MINERAL SEAL OIL (MENTOR 28)
MOLYBDENUM, INSOLUBLE
173
MARKED IRRITATION EYE, NOSE,
THROAT/ LUNG EDEMA
ACUTE SYSTEMIC TOXI CITY/MODERATE
IRRITATION EYE, (CONJUNCTIVITIS;
LUNGS/CENTRAL NERVOUS SYSTEM
EFFECTS
MARKED IRRITATION EYES, NOSE,
THROAT/LUNG EDEMA
LUNG CHANGES (SIDEROSIS)
MILD IRRITATION EYE, NOSE,
THROAT/NARCOSIS
INSOMNIA/ LASSITUDE (WEAP.I NESS)/
PALLOR SKIN/ANOREXIA (LOSS OF
APPETITE) /LOSS OF WEIGHT/MAL-
NUTR I TION/CONSTI PATI ON/ABDOM I NAL
PA I N/COLI C/HYPOTENSE/ANEM I A/
GINGIVAL LEAD LINE/TREMORS/P/
LYSIS WRIST
EXPLOS I VE/ASPHYXI ANT/NARCOS I S
ACUTE AND CUMULATIVE CENTRAL
NERVOUS SYSTEM DAMAGE/GASTRO-
INTESTINAL EFFECTS/GINGIVITIS
NARCOSIS/CUMULATIVE CENTRAL
NERVOUS SYSTEM EFFECTS/MILD
IRRITATION EYE, NOSE, THROAT
MILD IRRITATION EYE, NOSE,
THROAT/NARCOSIS
CHEMICAL ANOXIA (METABOLIC
CONVERSION TO CO)/CHRONIC LIVER
DAMAGE/CENTRAL NERVOUS SYSTEM
EFFECTS/NARCOSIS
ODOR/MODERATE IRRITATION EYE,
THROAT
'PARA-
ACCUMULATION IN LUNGS
SKIN IRRITATION, DERMATITIS AND
SUSPECT CARCINOGEN
CUMULATIVE LIVER AND KIDNEY DAMAGE'*
BLOOD DISORDERS/MILD IRRITATION
EYE, NOSE, THROAT, LUNG
-------
(CONT'D)
-4-
SUBSTANCE
OVEREXPOSURE SYMPTOMS
MONOCHLQROD!FLUOROETHANE
(FREGN-22)
NAPHTHA (COAL TAR)
NICKEL, METAL AND SOLUBLE
COMPOUNDS, AS Nl
NITRIC OXIDE
NITROGEN DIOXIDE
NUISANCE DUST
OIL MIST, MINERAL
ORTHO-DICHLOROBENZENE
OZONE
PARA-DICHLOROBENZENE
PETROLEUM DISTILLATES
(NAPHTHA)
PORTLAND CEMENT
PYRIDINE
SILICA-CRYSTALLINE
SOAPSTONE
SODIUM HYDROXIDE
SULFUR MONOCHLORIDE
SULFURIC ACID
CUMULATIVE LIVER DAMAGE
MODERATE IRRITATION EYE,
THROAT/NARCOSIS
SUSPECT CARCINOGEN/CUMULATIVE
LUNG DAMAGE/DERMATITIS
METHEMOGLOBINEMIA/CENTRAL
NERVOUS SYSTEM EFFECTS
CUMULATIVE LUNG DAMAGE (BRONCHITIS,
EMPHYSEMA)/LUNG EDEMA
NO SIGNIFICANT ADVERSE HEALTH
EFFECTS
ACCUMULATION IN LUNGS (PNEUMONITIS)
MARKED IRRITATION EYE, NOSE,
THROAT/LIVER DAMAGE
MARKED IRRITATION RESPIRATORY
TRACT/LUNG EDEMA
CUMULATIVE SYSTEMIC TOXIC ITY/
CATARACTS
MODERATE IRRITATION NARCOSIS
NUISANCE PARTICULATE/MILD'
IRRITATION EYE AND NOSE
CUMULATIVE LIVER, KIDNEY, AND BONE
MARROW DAMAGE/CNS EFFECTS
PNEUMOCONIOSIS (SILICOSIS)
PNEUMOCONIOSIS
MARKED IRRITATION EYE, NOSE,
THROAT,, LUNGS, SKIN
MARKED IRRITATION EYE, NOSE,
THROAT, LUNG
MARKED IRRITATION EYE,, NOSE,
THROAT, SKIN, BRONCHI/DENTAL
EROSION
174
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-5-
(CONT'D)
SUBSTANCE
QVEREXPQSURE SYMPTOMS
TALC (NON-ASBESTOS FORM)
1,1,2,2-TETRACHLOROETHANE
TETRACHLOROETHYLENE
TIN (INORGANIC COMPOUNDS.,
EXCEPT OXIDES)
O-TOLUIDINE
TRICHLOROETHYLENE
TRIETHYLAMINE
TURPENTINE
XYLENE (XYLOL)
ZINC CHLORIDE FUME
ZINC OXIDE FUME
PNEUMOCONIOSIS (TALCOSIS)
CUMULATIVE LIVER AND OTHER ORGAN
DAMAGE
CUMULATIVE LIVER AND CENTRAL
NERVOUS SYSTEM DAMAGE/NARCOSIS/
SUSPECT CARCINOGEN
ACUTE AND CHRONIC SYSTEMIC TOXIC I
METHEMOGLOBINEMIA/ACUTE SYSTEMIC
EFFECTS/SUSPECT CARCINOGEN
NARCOSIS/CUMULATIVE SYSTEMIC TOXIC
EFFECTS/SUSPECT CARCINOGEN
MARKED IRRITATION EYES, NOSE,
THR.OAT, LUNGS/LUNG EDEMA/CORNEAL
DAMAGE
MODERATE IRRITATION EYE, NOSE,
THROAT, BRONCHI, LUNGS, SKIN/
CUMULATIVE KIDNEY DAMAGE
MODERATE IRRITATION EYE, NOSE,
THROAT/NARCOSIS
MARKED IRRITATION EYE, NOSE, THROAT
LUNGS/ACUTE LUNG DAMAGE/SUSPECT
CARCINOGEN
ACUTE SYSTEMIC TOXICITY (METAL
FUME FEVER)
175
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176
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APPENDIX D
EXAMPLE HAZARD REPORTING FORM
177
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178
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Vhite Copy: Dept File
Veen Copy: Dept. Sends To Safety
ACTION A: To be filled out by employee
Pink Copy: Deposit in Hazard Report Box
Yellow Copy: Originator
HAZARD REPORTING FORM
3569
REPORTED TO:
REPORTED BY:
DATE:
DESCRIPTION & LOCATION OF HAZARD:
CAUSE
RECOMMENDATION TO CORRECT OR ELIMINATE SITUATION:
SECTION B: To be filled out by Supervisor
DATE RECEIVED:
DATE OF RESPONSE TO EMPLOYEE:
DATE ACTION COMPLETE:
ACTION TAKEN:
SUPERVISOR
DATE:
DEPT.SUPT.
DATE:
179
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180
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APPENDIX E
EPA RESPIRATORY PROTECTION PROGRAM GUIDELINE
181
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A U.S. Government Printing Office: 19I«—625-003/41110
182
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