Chapter 28

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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
• Firefighters beginning their training
are unlikely to make evacuation
decisions for several years
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
Hazardous Materials Management Systems
28.4
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
One of the first priorities should be to isolate the
area so as to prevent other people from becoming
involved with the incident.
28.6
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
Chemical Spills
• Top 10 chemical spills
–
–
–
–
–
–
–
–
–
–
Sulfuric acid
Hydrochloric acid
Chlorine
Ammonia
Sodium hydroxide
Gasoline
Propane
Combustible liquids
Flammable liquids
Natural gas
28.8
Chemical Spills (cont’d.)
• 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
Hazardous Materials Branch Positions
28.11
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
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.
28.13
The best position for first responders is uphill and
upwind from the release.
28.14
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
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.
28.16
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 nonpressurized
containers can breach in several
ways
28.18
Propane tank detonation.
28.19
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
28.20
Gases
• Incidents involving gases include
– Flammable gases
– Non-flammable gases
• Many departments carry gas
detection devices
• Most commonly released flammable
gases are natural gas and propane
• When fighting propane fire, large
quantity of water is applied quickly
and continuously
28.21
Master streams are used to
cool the hydrogen tanks on
a tube trailer. (Courtesy of
Maryland Department
Environment ERD)
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)
28.22
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
28.23
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)
28.24
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
28.25
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.
28.26
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
28.27
A leak of liquid oxygen on asphalt can present a shocksensitivity problem in addition to the increased risk of a fire.
28.28
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
28.29
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”
28.30
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
28.31
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)
28.32
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
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–
–
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Sick buildings
Odor complaints
Gas leaks inside a building
Explosions caused by gas grills
28.33
Decontamination
• If first responder is expected to
perform decontamination, then
training is required
• Decontamination is the physical
removal of contaminants from:
– People
– Equipment
– Environment
28.34
Types of Decontamination
• Four general types of decontamination
levels
–
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Emergency decontamination
Technical decontamination
Mass decontamination
Fine decontamination
• Process of decontamination is
chemical specific
28.35
One of the simplest forms of emergency
decon is the use of a hoseline.
28.36
Formal decontamination is used to remove any
further contamination that may remain after
gross decontamination.
28.37
Once additional resources arrive then the
advanced plan for mass decon can be
implemented.
28.38
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)
28.39
Decontamination Process
• Several variations to process
• Basic decontamination steps
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Tool drop
Gross decon
Scrubbing and rinse
PPE removal
SCBA removal
Clothing removal
Body wash and dry off
Medical evaluation, including rehydration
28.40
Methods of Decontamination
• General methods apply to:
– Humans
– Equipment
– Environment
• Consult with hazardous materials
team or a chemist prior to using any
method on a human
28.41
Absorption
• Spilled material picked up by
absorbent material
–
–
–
–
–
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Ground-up newspaper
Clay
Kitty litter
Sawdust
Charcoal
Poly fiber
• Compatibility needs to be
researched prior to use
28.42
Adsorption
• Material to be picked up bonds to
outside of adsorption medium
– Activated carbon
– Sand
• Many chemical facilities have
activated carbon stored
28.43
Chemical Degradation
• Ability to degrade a chemical varies
• Much like neutralization
• Degrade a chemical
– Another chemical is added
or
– Chemical is exposed to the elements
28.44
Dilution
• Dependent on chemical structure of
spilled material
• With corrosive, large quantities of
water are required
28.45
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
28.46
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
28.47
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
28.48
Neutralization
• Usually reserved for corrosive
materials
• Can reduce toxicity of a poisonous
material
• Consult with chemist prior to
performing this type of activity
28.49
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
28.50
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
28.51
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
28.52
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
28.53
Methods of Decontamination
28.54
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
escalation
28.55
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