11 defensive actions Flashcards
_____ usually present the greatest danger to first responders
Pressurized containers
Attempts to contain a liquid that has spilled onto a body of water must take into consideration the materials _____ and _____.
Specific gravity and miscibility with water
First responders who contain the release of a liquid hazardous material may then need to deal with a surface area capable of?
Producing large amounts of hazardous vapors
Any item used to build temporary barriers to control the release of a liquid hazardous material must be?
Compatible with the material released
First responders must always remember that any effort to excavate a containment area must first take what into consideration?
The presence of underground utilities
Attempts to contain the release of gases and vapors with water may produce a?
Hazardous water runoff
First responder should not operate below grade street valves for natural gas service unless?
Instructed to by the local utility company
Protective actions used by first responders include:
Isolating and denying entry to affected areas,
evacuation of these areas,
and in place protection in nearby structures
First responder should contact their local emergency management office for assistance when conducting operations that involve?
Evacuation or in place protection
The best way to decontaminate any protective clothing is?
To avoid contamination
First responders should always be prepared to decontaminate their protective clothing with at least?
gross wash prior to leaving the scene of most hazardous materials incidents
Upon arrival at the scene of any hazardous materials incident first responder should always adhere to guidelines provided in 29 CFR 1910. 120. These guidelines state the first responders at the operations level are those who respond in a?
Defense of fashion without actually trying to stop the release
Defense of actions that first responders can undertake include:
Preventing a release.
Containing the release of a liquid.
Containing the release of gases and vapors.
Containing the release of a solid.
Protective actions evacuation and in place protection
First responders should keep in mind that types of stress include:
Thermal, mechanical, and chemical
If the valve on a compressed gas cylinders damaged, gas or vapor may be released at a rate and volume faster than?
From a pressure relief device
Some pressure release devices may not operate properly if the container is not?
In an upright position
An important point that first responder should remember about pressure release devices is that they can only protect a container as long as they are?
The weak link in the container wall
Pressurize containers: damages especially troublesome when it occurs at?
Weld lines, or places where pieces of metal are joined when building the containers
First responder should remember that liquefied gases stored at normal atmospheric temperatures and pressures are already?
Boiling inside their containers
The weakening of a container wall from flame impingement usually occurs where?
The flame Contacts the vapor space
Whenever containers are exposed to fire with a decrease in container strength and increase of internal pressure, first responders must remember that the operation of the pressure relief valve is no guarantee that?
The container will not explode
The sound of gas and vapor escaping from an operating pressure relief device during a fire will increase in both volume and pitch as?
Internal pressure continues to rise due to external heating
The sound of gas and vapor escaping from an operating pressure relief device during a fire will increase in both volume and pitch as internal pressure continues to rise due to external heating. This change in sound should serve as a?
Warning to first responders that they may need to email you leave evacuate the area
The _____ of non-pressured containers are usually the weakest locations and therefore the most dangerous
Ends
Under many circumstances, there may be little first responders can do to prevent a release from a container that is already under pressure or when the internal pressure is steadily increasing. What may be the only option
Evacuating the area a safe distance
If an increase of internal pressure of a container is due to external heating, cooling the container or moving the containers from the source of the heat are options that are?
Dangerous at best
First responder should never assume that just because a spill is contained within a dike?
That there are no additional hazards present
First responder should always remember that any temporary barrier must be large enough to?
Contain the amount of material released
First responders may be able to control the flow of a liquid spill moving Downhill using a?
Diversion wall that directs the material to an area where it can be contained or result in less harm
Containment areas could be a depression along the road shoulder or a large hole, sometimes referred to as a
Retention basin, dug by first responders for the purpose of containing the runoff
Before using absorbent booms, first responders must remember that the material they are attempting to contain will need to have the following characteristics:
It cannot be miscible with water.
It must float on the surface of the water.
Absorbent boobs are generally not intended for use on large bodies of water where there may be?
Significant wave action or strong currents
Most absorbent booms are manufactured and blank sections
10 ft.
Under flow dams are containment devices that are best used in?
Narrow creeks and streams with flowing water
When building in underflow Dam, any pipe used must be large enough to allow the water to?
Flow freely. Larger flows will require larger, or perhaps multiple pipes
A first responder must remember that underflow dams are subject to erosion from the force of the moving water, and they must therefore?
Be monitored at all times
_____ means that whenever possible, temporary containment barriers should be backed up with additional barriers
Redundancy
The location of any containment device used in a body of water should always take into consideration the eventual?
Removal of the material
In addition to containing releases of liquid materials, some releases may be rendered safe by diluting them with water. In particular, when dealing with small spills involving blank the emergency response guidebook recommends applying flooding quantities of water
Small spills involving some types of oxidizers
While applying large quantities of water can dilute a spill to a safer and more stable concentration, before doing so a first responder should remember to first check with?
Local and state environmental officials and conduct research to determine potential outcomes
First responders should never apply water to a spill of hazardous materials unless they are confident that doing so will?
Not cause their efforts to become part of the problem
First responders may be able to identify compressed gas cylinders suspected of leaking since they may display _____ near the discharge opening
Frosting
The most difficult form of a material to control is a?
Gas or vapor
If the area where the ventilation controls are located is not safe to enter it may be better instead to have electric power to the building terminated from a remote site. Of course first responders must first determine in advance whether terminating electrical power will?
Then cause an emergency power generator to start
Releases of natural gas or propane maybe controlled if there is an?
External valve that can be operated safely by first responders
This valve must be remote from the source of release to avoid contamination and must clearly indicate the position of the valve
Attempting to control a release of chlorine gas with water spray may produce a?
Corrosive runoff
First responders should keep in mind that Waterspray applied to flammable gases and vapors will not always prevent ignition. Instead, air entrained in the fog stream could actually?
Mixed with the materials and cause some to reach their flammable range
Releases of solid hazardous materials usually occur in the form of?
Powder or a granular substance
First responder should always resist the urge to wet a spill of a powder or granular material in order to hold down the dust unless?
It is recommended
This is especially important for first responders to remember if the material is soluble with water
_____ are defense of tactics that can be used by first responders to minimize the exposure of people to hazardous materials
Protective actions
Protective actions include:
Isolating and denying entry to affected areas, evacuation of these areas, and in place protection and nearby structures
When dealing with transportation emergencies first responder should remember that each orange bordered page of the emergency response guidebook provides recommended distances for?
Immediate isolation of spill or leak areas under the heading public safety
The table of initial isolation and protective action distances is intended to show areas likely to be affected During?
The first 30 minutes after the materials are spilled
First responders should never rely on ____ as the only means to define an area affected by a hazardous materials release
Barrier tape
Efforts to isolate affected areas and deny entry are effective defensive tactics for most hazardous materials incidents. However those incidents associated with airborne hazards usually require additional defensive tactics in order to protect the public. Two generally accepted practices used by first responders are?
Evacuation and in place protection
Evacuation involves the removal of people from an area. The intent of in-place protection is that individuals remain in an affected area while inside structures with?
Doors and windows closed and sealed, and ventilation equipment switched off
A first responder should always know which people to contact in his local emergency management office regarding any actions he may wish to take regarding?
Evacuation or in place protection
Decontamination: the garment may be taken to a vendor for cleaning. If so the first responder must remember to provide?
A copy of the MSDS for the material that is the source of the contamination
What gas is usually the most difficult form of material to control, blank will present first responders with hazards similar to a gas
Vapors from liquids and dust from solids
