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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 temperature-protective clothing, chemical-protective clothing, liquid splash-protective clothing, and vapor-protective clothing.

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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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4

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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5

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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6

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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7

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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• High-Temperature Protective Clothing– Offers protection

from high temperatures only

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Hazardous Materials Protection (2 of 2)

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Chemical Protective Clothingand 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 Clothingand 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 contaminant-

specific.– 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 chemical-protective 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 chemical-protective 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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