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Chapter 35
Hazardous Materials Responder Health and Safety
Objectives: Hazardous Materials Operations Level
• Discuss the hazards of fire smoke.• Discuss the effects of carbon monoxide
and hydrogen cyanide on the body. • Describe methods for treating smoke
inhalation. • Discuss post-fire detection and monitoring
needs.
Objectives: Hazardous Materials Operations Level
• Discuss the purpose of detection devices at fire scenes.
• Discuss the various technologies available for fire-ground detection and monitoring.
• Discuss general fire-ground monitoring principles and practices.
Introduction • Combustion process liberates fire gases
and particulates.• Smoke often kills people before the flames
reach them.• Signs and symptoms of breathing smoke:
– Headache– Nausea– Dizziness– Fatigue
Introduction
• Fire agencies are increasingly mandating self-contained breathing apparatus (SCBA) use for longer periods.
• The environment invades the body when the breathable air supply is lost or interrupted.
Courtesy of Rob Schnepp.
Introduction • Chapter goals:
– Provide an overview of fire smoke hazards– Highlight link between smoke exposure and
chronic health effects• Smoke impacts every
aspect of the lives of those who work in or around it.
Courtesy of Rob Schnepp.
Introduction
• Questions to ask– Do crews wear SCBA until the building is
clear of smoke?– Have you established action levels for the
gases you are monitoring during post-fire detection and monitoring?
– Are personnel trained to understand detection and monitoring and to use the related technology appropriately?
Introduction
• Questions to ask – Are rapid intervention crews (RICs) located so
close that they are breathing smoke prior to being called into service?
– Is the command post located in drift smoke?– Does your prehospital care system have a
treatment protocol for smoke inhalation?– Is the local receiving hospital ready to treat a
significant smoke-related illness?
Harmful Components of Fire Smoke
• Carbon monoxide • Ammonia• Hydrogen chloride• Sulfur dioxide• Hydrogen cyanide• Carbon dioxide
Courtesy of Rob Schnepp.
Harmful Components of Fire Smoke
• Oxides of nitrogen• Formaldehyde• Acrolein• Polycylic aromatic hydrocarbons• Soot
Smoke Production
• Depends on– Chemical makeup of burning material– Temperature of combustion process– Influence of ventilation (oxygenation)
• Smoke is a collection of– Particulates– Superheated air– Gaseous chemical compounds
Synthetic Manufacturing and Construction Materials
• Extensive use affects fire behavior and smoke production.
• Synthetic substances ignite and burn fast, causing rapidly developing fires and toxic smoke.
Synthetic Manufacturing and Construction Materials
• Polyurethane mattress foam– Parent substances break down and bond with
each other when exposed to heat, creating new compounds.
– Some are irritants.• Hydrogen chloride and ammonia
– Some are acutely toxic when inhaled.• Carbon monoxide and cyanide compounds
Synthetic Manufacturing and Construction Materials
• Combustion liberates– Soot (visible)– Gases (invisible)
• Smoke is not only one thing– It is a dynamic, multifaceted mixture of gases
and particulates that changes from minute to minute at any fire.
Polycyclic Aromatic Hydrocarbons (PAHs)
• Commonly found in fire smoke• Probable or possible human carcinogen• Over 100 identified and categorized• Found in
– Vehicle exhaust– Tobacco smoke– Smoke generated from fires
Polycyclic Aromatic Hydrocarbons (PAHs)
• Can exist as particle or gas
• Also generated when grilling food
• May bond with soot, resulting in dermal and inhalation exposures
• Believed to be immunosuppressant
Courtesy of Rob Schnepp.
Polycyclic Aromatic Hydrocarbons (PAHs)
• Examples of PAHs include– Anthracene– Benzopyrene– Methylchrysene– Phenanthrene– Pyrene
Polycyclic Aromatic Hydrocarbons (PAHs)
• Contaminants to structural firefighting protective gear
• Dirty structural firefighting protective gear is:– Unhealthy– Likely to contribute to sustained exposure to
the fire long after leaving the scene
Carbon Monoxide and Hydrogen Cyanide
• Acutely toxic • Present to some degree in nearly all fires• Clinical interventions are available to
reverse adverse health effects of exposure.
Carbon Monoxide and Hydrogen Cyanide
• Findings of a study of toxic substances in smoke– Cyanide and carbon monoxide are important
determinants of smoke inhalation-related morbidity and mortality.
– Cyanide concentrations are directly related to probability of death.
Carbon Monoxide and Hydrogen Cyanide
• Findings of a study of toxic substances in smoke– Cyanide poisoning may be more predominant
than carbon monoxide poisoning as cause of death in fire victims.
– Cyanide and carbon monoxide may potentiate the harmful effects of one another.
Carbon Monoxide and Hydrogen Cyanide
• Hydrogen cyanide can incapacitate a victim, preventing escape from fire environment.– Increases exposure to toxic by-products of
combustion
Cyanide and Aerobic Metabolism
• Aerobic metabolism– Red blood cells carry
oxygen to and from cells.– Oxygen enters the
mitochondria of each cell.– Mitochondria convert
nutrients into ATP.
© Jones & Bartlett Learning.
© Jones & Bartlett Learning.
Cyanide and Aerobic Metabolism
• Cyanide compounds interfere with aerobic metabolism.– Prevent oxygen from entering mitochondria– Shuts down aerobic metabolism– Cells switch to anaerobic metabolism, which
produces toxic by-products that destroy the cell.
Carbon Monoxide• One of the most common
industrial hazards• Colorless and odorless• Produced during
incomplete combustion• Affects oxygen-carrying
capacity of red blood cells, causing hypoxia
© Jones & Bartlett Learning.
Smoke Inhalation• Very complex and challenging patient
presentation• Patient outcomes influenced by
– Extent and duration of smoke exposure– Amount and nature of toxicants in smoke– Degree of thermal burns to skin and lungs– Quantity/size of inhaled particulates (soot)– Patient’s age – Underlying medical conditions
Treating Smoke Inhalation • No nationwide standard protocol• Often boils down to supportive care
– Monitoring vital signs– Providing high-flow oxygen– Establishing intravenous (IV) lines– Performing advanced airway management
techniques– Cardiac monitoring– Rapid transport
Treating Smoke Inhalation
• Until the underlying cause of asphyxia is reversed at the cellular level, normal oxygenation is not possible– Requires administering antidote (oxygen)
to restore body’s ability to use oxygen– High-flow oxygen should be administered
for all cases of smoke inhalation.
Treating Smoke Inhalation
• Treatment for cyanide poisoning requires– Different kind of antidote– Oxygen administration
• Two types of antidote kits– Lilly kit– Cyanokit
Treating Smoke Inhalation • Lilly kit (Taylor or Pasadena kit)
– Also called cyanide antidote kit (CAK)– Contains amyl nitrate, sodium nitrate, and sodium
thiosulfate– Nitrates convert hemoglobin to methemoglobin to
attract cyanide– Restores cell’s ability to take in oxygen– Thiosulfate bonds with cyanide, rendering it less
harmful– Can cause blood pressure to drop
Treating Smoke Inhalation
• Cyanokit (hydroxocobalamin)– Relatively benign with minimal side effects– Benign, minimal adverse effects– Can be administered without first verifying
presence of cyanide
Treating Smoke Inhalation
• Consult NFPA 473, Section 6.4, “Mission-Specific Competencies Advanced Life Support (ALS) Responder Assigned to Treatment of Smoke Inhalation Victim,” as a reference source for treating smoke-related illness and injury
Post-Fire Detection and Monitoring
• No best practice for detection and monitoring in the fire environment
• Atmospheric monitoring technology and devices should be– User-friendly– Durable– Cost-effective– Easy to maintain
Post-Fire Detection and Monitoring
• Targeting certain gases– Broadly representative of airborne environment– Not an exact indicator of the presence, absence,
or concentration of other gases or particulates• Wearing SCBA
– Gold standard of respiratory protection– Best way to reduce possibility of inhalation
exposures
Post-Fire Detection and Monitoring
• Three primary uses for detection devices– Rescue response (including confined space)– Building collapse and trench rescue– Carbon monoxide detector responses
Why Use Detection Devices at the Fire Scene?
• No single device detects all fire gases and particulates in fire smoke.
• Initial detection seeks to determine– What substances you want to detect and/or
monitor– At what concentrations they pose a risk of
exposure
Why Use Detection Devices at the Fire Scene?
• National Institute for Occupational Safety and Health (NIOSH) levels for chemicals in the workplace– Immediately dangerous to life and health (IDLH)
• Requires breathing apparatus or withdrawal– Short-term exposure limit (STEL)
• 15-minute exposure; limit four times a day– Recommended exposure limit (REL)
• 10-hour exposure
Why Use Detection Devices at the Fire Scene?
• Most common detection method involves single-gas or multi-gas detection devices.– Environment considered IDLH if levels are at
or above 1200 ppm.– REL is safer end point for detection and
monitoring.– Next step is to widen the focus and evaluate
for multiple gases with a multi-gas meter or multiple technologies.
Fire Scene Detection and Monitoring Technologies
• Three technologies are commonly used– Electrochemical sensors– Photoionization detector (PID) sensor– Colorimetric tubes
Electrochemical Sensors• Contain chemical reagent that reacts with
target gas, resulting in a meter reading.• Typical sensors include
– Oxygen– Hydrogen cyanide– Carbon monoxide– Hydrogen sulfide– Ammonia– Chlorine Courtesy of Rob Schnepp.
Electrochemical Sensors• Concerns
– React to other gases– Can be easily overwhelmed and will max out
with regard to their readings– Fail to the zero point
• Before use, devices must be– Calibrated properly– Bump tested
• Reaction times of sensors vary
Photoionization Detector (PID)• Stand-alone unit or multi-gas meter• Ultraviolet light ionizes gases in sensor• Detects materials such as
– Benzene– Acetone– Toluene– Ammonia– Ethanol– Butane
Courtesy of Rob Schnepp.
Photoionization Detector (PID)
• Primarily detects organic materials• Most common inorganic material detected
is ammonia.• Will not detect
– Carbon monoxide – Hydrogen cyanide– Compounds such as natural gas
Photoionization Detector (PID)
• Reaction time of 1 to 2 seconds• Most have protective filter
– Keeps out some particulate material
– Must replace frequently at fire scene
• Water resistant, not waterproof Courtesy of Rob Schnepp.
Colorimetric Tubes
• Detect specific substances and/or confirm readings of other technologies
• Identify presence and/or levels of known gas or vapor and unidentified substances
• Designed to detect chemical families but can be set to detect a specific chemical
Colorimetric Tubes
• Air moves through tube by use of piston-style pump or bellows pump.
• Easy to use• Require little preparation• Single-use only• Pump is reusable.
Courtesy of Rob Schnepp.
Fire Scene Detection and Monitoring Practices
• Detection devices not necessary during active interior structural firefighting – High heat, particulates, and steam or
water detrimental to instruments• Assume environment is IDLH.
– Wear firefighting personal protective equipment (PPE), including SCBA.
• Limit air monitoring during active firefighting to exterior operations.
Fire Scene Detection and Monitoring Practices
• Start detection and monitoring with exterior evaluation of footprint of fire.– Work inward toward crews.– Fire gas production stops only when all
substances involved in fire are cooled below point they decompose and off-gas.
– Initiate interior monitoring when all visible particulate has been ventilated.
Fire Scene Detection and Monitoring Practices
• Fire investigators should evaluate environment prior to beginning work.
• Ventilation practices can change and influence interior atmosphere.– Gasoline-powered positive
pressure ventilation (PPV) fans can raise carbon monoxide levels above the REL. Courtesy of Rob Schnepp.
Fire Scene Detection and Monitoring Practices
• Detection at the fire scene not an exact science due to– Limitations of instrumentation– Dynamic nature of fire scene– Narrow view of using only one or two gases
as indicators of airborne environment
Fire Scene Detection and Monitoring Practices
• Cumulative smoke exposures over the course of a career can be dangerous.
• Recommendations– Wear your SCBA for longer periods of time at the
fire scene.– Keep your structural firefighting protective gear
clean.– Shower after working at a fire.– Get regular health evaluations and cancer
screenings.
Summary
• When asked about fire fatalities, fire fighters typically observe that smoke kills people before the flames ever get to them, and fire death statistics prove likewise.
Summary
• Most people identify carbon monoxide as the main harmful component of fire smoke. – Less often acknowledged are compounds
such as ammonia, hydrogen chloride, sulfur dioxide, hydrogen sulfide, hydrogen cyanide, carbon dioxide, the oxides of nitrogen, formaldehyde, acrolein, polycyclic aromatic hydrocarbons, and soot.
Summary
• Studies performed in Paris, France, and Dallas County, Texas, focused on carbon monoxide and hydrogen cyanide specifically because they are acutely toxic, present to some degree in nearly all fires, and have clinical interventions available to reverse the adverse health effects of the exposure.
Summary
• Nationwide, there is no standard protocol for treating smoke inhalation, leaving paramedics and other prehospital care providers with limited guidance or training to properly care for smoke inhalation victims.
Summary
• Many fire agencies are investing in technologies for detecting toxic gases at the fire scene without a clear understanding of the mission, the limitations of the devices, or what it means to check to see if the building is clear and, more commonly, when it is safe to remove SCBA.
Summary • NIOSH establishes safe levels for
chemical exposures in the workplace; however, the values are for average worker exposure and can be only estimated for the rigors of firefighting.
• Equipment such as electrochemical sensors, photoionization detectors, and colorimetric tubes can all be used to monitor conditions at a fire scene.
Summary
• Regardless of which instrument is selected, hazardous materials responders should develop a defined and systematic strategy for the use of detection devices.
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