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Chapter 28
Hazardous Materials: Protective Actions
Introduction• There are general tactics when responding
to a hazardous materials incident• Tactical considerations provided are for
general situations– May not apply to specific cases
• Firefighters beginning their training are unlikely to make evacuation decisions for several years– Material in this chapter should be kept in mind
for the future
28.2
Hazardous Materials Management Processes
• Several different management processes exist– 8-Step Process– GEDAPER Process– DECIDE Process
• Cores of all systems are basically the same: protection of life, property, environment
• Group of responders will fit into the ICS using one of these processes, or a combination
28.3
28.4
Table 28-1 Hazardous Materials Management Systems
Isolation and Protection• One of the most important tasks• Methods:
– Barrier tape– Use of law enforcement– Traffic barriers– Use of emergency vehicles to block
access
• Control incident quickly
28.5
28.6
Figure 28-1 One of the first priorities should be to isolate the area so as to prevent other people from becoming involved with the incident.
Rescue• Rescue of victims from suspected hazard
area can be extremely controversial• Local protocol and SOPs must be
considered• Evaluate incident• Take into account response and
notification time• Once out of the area, decontaminate• Procedures should be in place for rescuing
trapped victims
28.7
Top 10 Chemicals Spilled
• The top 10 chemicals spilled are:– Sulfuric acid– Hydrochloric acid– Chlorine– Ammonia– Sodium hydroxide– Gasoline– Propane
28.8
Top 10 Chemicals Spilled (cont’d.)
• The top 10 chemicals spilled are: (cont’d.)– Combustible liquids– Flammable liquids– Natural Gas
• Response to an incident involving these chemicals should be no different than a response to a bedroom fire
28.9
Site Management• Management of hazardous materials
incident can be difficult• When involved in a chemical release, many
agencies can be involved• Liaison must be established between all
agencies– Requires a minimum of two safety officers
• Hazardous materials safety officer should be trained to Technician or Specialist level
28.10
28.11
Table 28-2 Hazardous Materials Branch Positions
Establishment of Zones• Refers to areas that are established
to identify various isolation points• Hot zone may be referred to as:
– Exclusion zone– Isolation area– Hazard area
• Warm zone: contamination reduction zone
• Cold zone: support area
28.12
28.13
Figure 28-7 The establishment of zones is usually based on the types of hazards that may be present. For general chemical spills, the zones established are referred to as the hot, warm, and cold zones.
28.14
Figure 28-8 The best position for first responders is uphill and upwind from the release.
Evacuations and Sheltering in Place
• Best way to determine evacuation or shelter is to conduct real-time air monitoring
• If a decision is made to evacuate, a suitable location needs to be found– In most cases, sheltering in place is safer than
evacuation
• When sheltering, citizens should shut all windows and doors– Shut off air handling systems
28.15
28.16
Figure 28-9 Standard shapes for plumes or vapor clouds may form after a gas is released. The exact type varies with the topography and the buildings in the area.
Common Incidents• Overview of common incidents• Types of releases in each DOT
hazard class• Recommendations provided are only
suggestions• Local policies and procedures should
be followed
28.17
Types of Releases• Type of release can be classified as:
– Breach in a container– Release within containment system
• Several ways of looking at potential release of a chemical:– Chemical is stressed– Container is stressed
• Pressurized and non-pressurized containers can breach in several ways
28.18
28.19
Figure 28-10 Types of container breaches.
28.20
Figure 28-11 Propane tank detonation.
Explosives• All persons must be removed from the area• Defensive operation should be established• Many other considerations come into play if
fire is not directly impacting explosives• Examples of incidents involving explosives
– Assisting a bomb squad– Shipment of explosives involved in an accident– Explosives brought by citizens to fire department
28.21
Gases• Incidents involving gases include:
– Flammable gases– Non-flammable gases
• Many departments carry gas detection devices
• Most commonly released flammable gases:– Natural gas– Propane
• When fighting propane fire, large quantity of water is applied quickly and continuously
28.22
28.23
Figure 28-18 Master streams are used to cool the hydrogen tanks on a tube trailer. (Courtesy of Maryland Department Environment ERD)
Figure 28-19 Note the severe damage to this high pressure hydrogen tube trailer. It was involved in a traffic accident and caught fire. (Courtesy of Maryland Department Environment ERD)
Flammable and Combustible Liquids
• Leading category for most common type of release
• Considerable runoff when fighting this type of fire
• Problems when using foam– Damaging to environment– Slippery
28.24
28.25
Figure 28-23 A diesel tank truck cab caught fire, impinging on the cargo tank. A quick and aggressive response by the Washington, DC, and Prince Georges County Fire Departments was able to knock down the fire before the contents were ignited. If the tank had become compromised, firefighting would have been very challenging because the tank truck was on a significant incline. Burning fuel would have traveled down the highway, possibly into storm drains. (Courtesy of Maryland Department Environment ERD)
Flammable Solids, Water Reactives, and Spontaneously
Combustible Materials• Specific identity and emergency response
information are crucial• Responders have experience with
flammable solids• Water-reactive group defined in two ways• Materials that are spontaneously
combustible are kept stable during transport
28.26
28.27
Figure 28-27 In this photo eight ounces of magnesium shavings were in a pool of burning diesel fuel. When the magnesium was heated, a slight water mist was sprayed over the fire. The white sparks are from the magnesium and the fireball is from the reaction as well. Relate the size of this violent reaction from a cup of magnesium to that of a truckload of magnesium.
Oxidizers and Organic Peroxides
• Can have explosive characteristics• Best known oxidizer is ammonium
nitrate• Liquefied oxygen (LOX) presents
more hazards in addition to supporting combustion
• Pool chemicals are another common oxidizer
28.28
28.29
Figure 28-28 A leak of liquid oxygen on asphalt can present a shock-sensitivity problem in addition to the increased risk of a fire.
Poisons• Toxic in varying degrees but should
be treated as poisonous by first responders
• Most common incidents result from pesticides and agricultural chemicals
• Commercial home fertilizers do not present much risk to responders – Unless in large quantities
28.30
Radioactive Materials• Incidents are rare• Radioactive materials commonly
used in community– Smoke detectors– Ground imaging equipment– Medical community
• Follow the adage:– “Time, distance, and shielding”
28.31
Corrosives• Most common incidents:
– Sulfuric acid– Hydrochloric acid– Sodium hydroxide
• Chemical protective clothing is required
• Wash splashed material quickly• Chemical neutralization may be the
best choice
28.32
28.33
Figure 28-29 The shipping papers did not indicate the presence of nitric acid. The brown vapor cloud is a result of a chemical reaction between bromine and red fuming nitric acid. When the hazardous materials team opened the back of the truck, they were greeted with these vapors. The team members in the photograph retreated when the vapors were released from the back of the truck and changed into chemical protective clothing. (Courtesy of Maryland Department Environment ERD)
Other Incidents• Impossible to outline each specific
action that a first responder should take at a chemical release
• Many toxic materials are odorless and colorless
• Common incidents:– Sick buildings– Odor complaints– Gas leaks inside a building– Explosions caused by gas grills
28.34
Decontamination• If first responder is expected to
perform decontamination, then training is required
• Decontamination is the physical removal of contaminants from:– People– Equipment– Environment
28.35
Types of Decontamination• Four general types of decontamination
levels:– Emergency decontamination– Technical decontamination– Mass decontamination– Fine decontamination
• Process of decontamination is chemical specific
28.36
28.37
Figure 28-31 One of the simplest forms of emergency decon is the use of a hoseline.
28.38
Figure 28-33 Formal decontamination is used to remove any further contamination that may remain after gross decontamination.
28.39
Figure 28-35B Once additional resources arrive then the advanced plan for mass decon can be implemented.
28.40
Figure 28-40 An example of the decontamination vehicle completely set up. The use of the tent adds an additional layer of privacy. (Courtesy of Maryland Department Environment ERD)
Decontamination Process• Several variations to decontamination
process• Basic decontamination steps:
– Tool drop– Gross decon– Scrubbing and rinse– PPE removal– SCBA removal– Clothing removal– Body wash and dry off– Medical evaluation, including rehydration
28.41
28.42
Figure 28-36 Mass decon plan for herding mass numbers of potentially contaminated people.
Methods of Decontamination• General methods of
decontamination apply to:– Humans– Equipment– Environment
• Consult with hazardous materials team or a chemist prior to using any method on a human
28.43
Absorption• Spilled material picked up by
absorbent material:– Ground-up newspaper– Clay– Kitty litter– Sawdust– Charcoal– Poly fiber
• Compatibility needs to be researched prior to use
28.44
Adsorption• Material to be picked up bonds to
outside of adsorption medium:– Activated carbon– Sand
• Many chemical facilities have activated carbon stored
28.45
Chemical Degradation• Ability to degrade a chemical varies• Much like neutralization• To degrade a chemical:
– Another chemical is added
or– Chemical is exposed to the elements
28.46
Dilution• Dependent on chemical structure of
spilled material• With corrosive, large quantities of
water are required
28.47
Disinfection• With humans, a 0.5 percent bleach
and water solution can be used for some etiological contaminants
• Contact time is needed for success• Plain water has proven effective for
biological contaminants
28.48
Evaporization• Is allowing a chemical to evaporate
changing its state of matter?• Solid or liquid left in the open will
eventually change to vapor (depending on vapor pressure)
• Chemical approaching boiling point will evaporate
• Material does not disappear but merely changes its state of matter
28.49
Isolation and Disposal• One of the easiest forms of
decontamination• Isolate the contaminant, collect it
using protective clothing, and then dispose of contaminant
• Follow appropriate regulations
28.50
Neutralization• Usually reserved for corrosive
materials• Can reduce toxicity of a poisonous
material• Consult with chemist prior to
performing this type of activity
28.51
Sterilization• Two primary methods of
sterilization:– Combination of steam and high heat– Chemical sterilization
• Steam and high heat useful for etiological contamination
• Chlorine dioxide used to decontaminate buildings with anthrax contamination
28.52
Solidification• Depending on solidification agent
used, it may alter the suspect agent• Some cases, solidification agent has
no effect on agent – Will reduce hazard and enable
sampling
• Chemical compatibility must be confirmed
28.53
Vacuuming• Used for solids, such as dust or fibers• Use a vacuum with a HEPA filter• Special vacuums are made for
picking up mercury– Prevent mercury vapors from entering
the air
28.54
Washing• Done with soap and water• One of the more effective
decontamination solutions• Soap and water merely removes
contaminant• Use air monitors to test effectiveness
of decontamination• Some response teams and
emergency plans outline incident levels
28.55
28.56
Table 28-4 Methods of Decontamination
Lessons Learned• Protective actions used for a variety
of purposes• Management of a chemical-release
is not an easy task• Determination for decontamination
can also be a difficult decision• Choosing method of
decontamination can be difficult• Provide isolation and prevent
escalation28.57