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Hazardous
Materials:
Scene Safety
and Control
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Objectives (1 of 4)
• Describe hazardous materials personal
protective equipment.
• Identify the purpose, advantages, and
limitations of structural firefighting
protective clothing, high temperatureprotective clothing, chemical-protective
clothing, liquid splash-protective
clothing, and vapor-protective clothing.
2
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Objectives (2 of 4)
• Discuss respiratory protection in a
hazardous material incident.
• Describe the levels of hazardous
materials personal protective
equipment.
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Objectives (3 of 4)
• Identify skin-contact hazards
encountered at hazardous materials
incidents.
• Describe the safety precautions to be
observed, including those for heat and
cold stress, when approaching and
working at hazardous materials
incidents.
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Objectives (4 of 4)
• Describe the physical capabilities
required and limitations of personnel
working in personal protective
equipment.
• Describe techniques used to isolate
hazard areas and deny entry.
• Describe the importance of the buddy
system and back-up personnel.
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Introduction
• Scene control, site management, and
personal accountability are critical.
• Safe handling of hazardous materials
incident determined in the first five
minutes
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Levels of Damage
• Threshold Limit Value/Short-Term Exposure
Limit (TLV-STEL)
• Threshold Limit Value/Time Weighted
Average (TLV-TWA)
• Threshold Limit Value/Ceiling (TLV-C)
• Threshold Limit Value/Skin (TLV-S)
• Permissible Exposure Limit (PEL)
• Immediately Dangerous to Life and Health
(IDLH)
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TLV-STEL
• Maximum concentration a person can
be exposed to in 15-minute intervals, up
to four times a day without damage.
– Minimum one hour rest between exposures
• Lower the TLV-STEL, the more toxic the
substance.
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TLV-TWA
• Maximum concentration a person could
be exposed to 8 hours a day, 40 hours a
week without damage
• The lower the TLV-TWA, the more toxic
the substance.
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TLV-C
• Maximum concentration a person could
be exposed to, even for an instant.
• The lower the TLV-C, the more toxic the
substance.
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TLV-S
• Indicates that direct or airborne contact
could result in a possible and significant
exposure by absorption through the
skin, mucous membranes, and eyes
• Take appropriate measures to minimize
contact with the skin.
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PEL
• Maximum, time-weighted concentration
to which 95% of healthy adults can be
exposed over a 40-hour workweek
without damage
– Also called the REL (Recommended
Exposure Level)
– Comparable to the TLV-TWA
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IDLH (1 of 3)
• An atmospheric concentration of any
toxic, corrosive, or asphyxiant that
poses an immediate threat to life or
could cause irreversible or delayed
adverse health effects
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IDLH (2 of 3)
• Three types of IDLH atmospheres:
– Toxic
– Flammable
– Oxygen-deficient
• IDLH atmospheres require the use of
SCBA or equivalent protection.
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IDLH (3 of 3)
• Below IDLH levels, most healthy
individuals could escape the
atmosphere without respiratory
protection without irreversible damage
to their health.
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Determining Atmospheric Safety
• Atmospheric monitoring requires
specific training and equipment.
• Three types of atmospheres at a
hazardous materials incident:
– Safe
– Unsafe
– Dangerous
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Selection of Proper PPE
• Turnout gear will not protect against
many hazardous materials.
• PPE is selected based on the specific
properties of the products involved.
• The IC should approve the level of PPE
to be used on an incident.
• Fire fighters should not use PPE they
have not been trained to use.
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Types of PPE
• Clothing and Work Uniforms
• Structural Firefighting Protective
Clothing
• High-Temperature Protective Clothing
• Chemical Protective Clothing and
Equipment
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Hazardous Materials Protection
(1 of 2)
• Clothing and Work Uniforms
– Offers no protection from hazardous
materials
• Structural Firefighting Protective
Clothing
– Offers almost no chemical protection
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Hazardous Materials Protection
(2 of 2)
• High-Temperature
Protective Clothing
– Offers protection
from high
temperatures only
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Chemical Protective Clothing
and Equipment (1 of 2)
• Designed to prevent chemicals from
coming in contact with the body
– Have varying degrees of resistance
• Chemical-resistant materials
– Designed to inhibit or resist the passage of
chemicals into and through the material
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Chemical Protective Clothing
and Equipment (2 of 2)
• Important Concepts
– Penetration
– Permeation
– Degradation
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Penetration
• Flow or movement of a hazardous
chemical through closures, seams,
porous materials, pinholes, or other
imperfections
• Liquids and solids can penetrate.
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Permeation
• Process by which a hazardous chemical
moves through a material at the
molecular level
• Implies the chemical going through the
material itself, rather than through an
opening in the material
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Degradation
• Physical destruction or decomposition
of a material due to chemical exposure,
general use, or ambient conditions
• Usually evidenced by signs such as
charring, shrinking, swelling, color
changes, or dissolving
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Garment Construction
• Single-piece
– Completely encloses wearer
– Known as an encapsulated suit or acid suit
• Multi-piece
– Works with the wearer’s respiratory
protection, an attached or detachable
hood, gloves, and boots
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Material Used In Construction
•
•
•
•
•
Butyl rubber
Tyvek®
Saranex
PVC
Vitron
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Liquid Splash-Protective Clothing
• Protects skin and eyes
• Does not protect
against gases or vapors
• Should not be used for
incidents involving
liquids that emit vapors
• May be worn over or
under structural
firefighting clothing
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Vapor-Protective Clothing
– Must be used when
hazardous vapors
are present
– Traps heat and
perspiration
– Must be used in
conjunction with
respiratory protection
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Respiratory Protection Devices
• Self-contained breathing apparatus
(SCBA)
• Supplied air respirator (SAR)
• Air-purifying respirator (APR)
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SCBA
• Prevents exposure through inhalation or
ingestion
• Should be mandatory for fire service
personnel
• Fire fighters must know the limitations of
SCBA
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SAR
• User is connected to an
external air source by a
hoseline that connects
to the facepiece.
• Useful during extended
operations
– Decontamination
– Clean-up
• Hoseline may restrict
movement.
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APRs (1 of 2)
• Filter particulates
and contaminants
from the air
• Should only be used
when:
– Type and amount of
contaminants are
known
– Atmosphere is not
oxygen-deficient
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APRs (2 of 2)
• Limitations:
– Filtering cartridges are contaminantspecific.
– Atmosphere must be continuously
monitored.
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Level A Protection
• Fully encapsulating
suit
• Highest level of
protection
– Effective against
vapors, gases, mists,
dusts
• Requires SCBA or
SAR
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Level B Protection
• Consists of chemicalprotective clothing,
boots, gloves, and
SCBA
• Used when high
respiratory protection
but less skin protection
required
• Type of gloves and
boots worn depends on
the chemical involved
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Level C Protection
• Standard work clothing
plus chemical-protective
clothing
• Appropriate when:
– Type of airborne
substance is known
– Concentration is
measured
– Criteria for using an APR
is met
– Skin or eye exposure is
unlikely
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Level D Protection
• Lowest level of
protection
• Used when:
– Atmosphere contains no
known hazard.
– Work functions preclude
splashes, immersion, or
potential for inhalation.
• Should be used for
nuisance contamination
only
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Skin Contact Hazards (1 of 4)
• Principal dangers of hazardous
materials are toxicity, flammability, and
reactivity.
• Hazardous materials can harm the
inadequately protected body.
• Assume the worst and leave the largest
possible safety margin.
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Skin Contact Hazards (2 of 4)
• Skin can absorb harmful toxins without
any sensation to the skin itself.
– Do not rely on pain or irritation as a
warning of absorption.
• Some substances are lethal if only a
few drops contact the skin.
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Skin Contact Hazards (3 of 4)
• Skin absorption is enhanced by cuts,
abrasions, heat, and moisture.
• Absorption rate depends on body part.
– Chemicals absorbed through the skin on
the scalp much faster than through the
forearm
– Eyes have one of the fastest means of
exposure.
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Skin Contact Hazards (4 of 4)
• Corrosives do not have to be absorbed
to do damage.
– Acids
– Have affinity for moisture
• Can burn respiratory tract
– Alkalis
• Cause deep burns
• Turns tissue to soapy liquid
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Safety Precautions
• Standard safety precautions for
firefighting apply to hazardous materials
incidents.
• In addition, special attention must be
paid to temperature and stress.
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Excessive Heat Disorders
• Fully encapsulating and chemicalprotective suits do not “breathe.”
– Personnel in such suits are at greater risk
for heat-related emergencies.
• Heat-related emergencies:
– Heat Exhaustion
– Heat Stroke
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Heat Exhaustion (1 of 2)
• Mild form of shock caused by
overheating when the body cannot
dissipate heat
• Signs and symptoms include:
– Elevated core temperature
– Weakness
– Profuse sweating
– Dizziness
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Heat Exhaustion (2 of 2)
• Emergency Action:
– Remove victim from the source of heat
– Rehydrate
– Provide cooling
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Heat Stroke (1 of 2)
• Life-threatening condition resulting from
the total failure of the body’s
temperature-regulation capacity
• Signs and symptoms include:
– Reduction or cessation of sweating
– Body temperature at or above 105ºF
– Rapid pulse
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Heat Stroke (2 of 2)
• This is a true medical emergency
requiring immediate transport to a
medical facility.
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Prevention of Heat-Related
Emergencies
• Prehydrate with 8 to16 oz. of water
before donning PPE.
• Rehydrate with 16 oz. of water for each
SCBA cylinder used.
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Cold-Related Emergencies (1 of 3)
• Two types of cold exposure:
– Materials-related
• Liquified gases and cryogenic materials
• Gases released under pressure
– Weather-related
• Wind speed and temperature
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Cold-Related Emergencies (2 of 3)
• Despite temperature, fire fighters will
sweat.
– Wet clothing extracts heat from the body
up to 240 times faster than dry clothing.
– May lead to hypothermia
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Cold-Related Emergencies (3 of 3)
• Prevention
– Wear appropriate, layered clothing.
– Warm up in heated shelters or vehicles.
– Keep layers next to skin dry.
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Physical Capability Requirements
• Hazardous materials responses are
physically and psychologically stressful.
• A health and safety management
program is needed to ensure
responders are capable of meeting
challenges of the work.
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Medical Surveillance Program
(1 of 2)
• Part of the health and safety
management program.
• Includes:
– Fitness for duty determinations
– Detection of changes in body systems due
to physical and/or chemical exposures
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Medical Surveillance Program
(2 of 2)
• Pre-entry values should be attained
within 15 to 20 minutes after leaving
environment.
• Treat and transport anyone who does
not return to normal values within 20
minutes.
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Response Safety Procedures
• Actions for Awareness-level responders
– Isolate and deny entry.
– Try to identify products.
– Follow the NAERG.
– Follow SOPs.
– Eliminate possible ignition sources.
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Control Zones (1 of 2)
• Designated areas at a hazardous
materials incident based upon safety
and the degree of hazard
• Types:
– Hot zone
– Warm zone
– Cold zone
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Control Zones (2 of 2)
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Hot Zone
• Area immediately around the incident
site
• Contains personnel and equipment
needed to control the release
• Is contaminated
• Access is limited.
• Entries and exits are logged.
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Warm Zone
• Staging area for entering and leaving
the hot zone
• Contains an access corridor and a
decontamination corridor
• Only essential personnel allowed.
• Personnel must be in appropriate PPE.
– Generally one level below what is used in
the hot zone
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Cold Zone
• Safe area where special protective
clothing is not needed
• Restricted area
• Cold zone operations include:
– Personnel staging
– Command post
– Medical support area
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Isolation Techniques (1 of 2)
•
•
•
•
Approach from uphill.
Resist the urge to rush in.
Establish a perimeter.
Ensure perimeter control devices do not
impede rapid evacuation.
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Isolation Techniques (2 of 2)
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Buddy System and Back-up
Personnel
• Back-up personnel must be ready to
respond quickly into the hot zone to
rescue any personnel if an emergency
occurs.
• Work in teams of two.
• Do not rely solely on radios for
communication in the hot zone.
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Summary (1 of 4)
• PPE is product-specific.
– No such thing as generic chemical-protective suit
– PPE has limitations; fire fighters must know them.
• Four recognized levels of protective clothing
– Level A provides the most protection.
– Level D provides almost no protection.
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Summary (2 of 4)
• Use of respiratory protection is essential
on most hazardous materials incidents
• Be aware of and know how to handle
both heat- and cold-related
emergencies
• Monitor responder vital signs before,
during, and after a hazardous materials
incident.
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Summary (3 of 4)
• Resist the urge to rush in.
• Only fire fighters trained to the
technician or specialist levels should
enter the hot zone.
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Summary (4 of 4)
• Work in teams of two in the hot zone.
• Ensure a back-up team is prepared to
enter the hot zone to effect a rescue.
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