Flashcards in Haz-mat-01 Alternate Fuels Deck (40)
What are some properties of LP Gas?
1.2.1 LP gases are non-toxic and non-poisonous. They are however slightly anesthetic.
Asphyxiation can occur due to oxygen displacement.
1.2.2 LP gas is odorless, an odorizing agent is added only when it is processed for
1.2.3 LP gas is flammable.
1.2.4 In the liquid state, LP gases present a hazard similar to a highly volatile
flammable liquid but with more rapid vaporization.
1.2.5 LP gases are heavier then air (1.5 to 2 times heavier).
For a tanker that is leaking gas or on fire, if not engaged in operations what is the distance everyone should be placed from tanker ?
1.3.3 Keep everyone, not actually engaged in operations, at least 1000 feet from the
front and rear of the tank and 500 feet from the sides.
Tank surfaces that are exposed to heat, either from auto exposure or fire from
another source, can be protected by supplying large quantities of water on them. How shall the tank be approached
Approach the tank from the sides, applying water to all exposed surfaces as well
as piping and valves.
Note Approach from UPWIND
Where escaping gas is on fire and the flow cannot be shut off, application of large
quantities of water on the tank and piping will permit controlled burning,
allowing the fire to consume the contents of the tank without the danger of tank or
pipe failure. Make certain of what ?
Make certain that fire is NOT extinguished
What types of extinguishers are effective on small LP gas fires ?
Portable dry chemical extinguishers are effective on small LP gas fires. Carbon
dioxide extinguishers can also be used. They should be applied at the base of the
Where does tank failure usually occur under fire conditions ? Is there any way to tell where this area is ?
Tank failure under fire conditions usually occurs in the vapor area of the tank
when sufficient water cannot be applied to prevent the metal from softening or
weakening to a point where metal failure occurs.
NOTE: Sometimes Frost line shows the liquid level
What are some signs that tank failure in imminent ? What shall be done when these symptoms are present ?
Before tank failure occurs, the rise in pressure within the tank will cause an
increase in the volume of fire, or a rise in the noise level or both. This may or
may not be accompanied by a bubble or blister forming on the tank shell. When
any of these symptoms are present, the operating forces should be withdrawn to a
Propane is a liquefied gas stored in cylinders at a temperature ______ its boiling
point and remains under pressure and in liquid form only so long as the container
remains _____ to the atmosphere.
Heat applied to the cylinder will cause excessive pressure to build up in the
cylinder opening the relief valve. One cubic foot of liquid will expand ______ times
as a gas.
ABOVE, Closed, 270
2.4.3 There is a great possibility that a cylinder involved in a fire will "BLEVE". A proper performance of a relief valve will prevent this ?
A satisfactory performance of a relief valve can not prevent a BLEVE.
What does BLEVE stand for ?
Boiling Liquid Expanding Vapor Explosion.
A BLEVE can occur in a matter of
What ID number would you find on a placard that identifies propane ?
Page 9 Hazmat 1
Areas of Exposure
A. The three areas of exposure during a vehicle leak or fire in a propane
(LP-Gas) system are:
1. The engine compartment.
2. The fuel line from the tank to the automatic shutoff valve.
3. The tank area
Many vehicles are dual-fueled and use both propane and gasoline
alternatively. A fire can originate with a gasoline leak and may eventually
involve both fuels. What is a basic principle with a propane fire ?
A BASIC PRINCIPLE IS THAT A PROPANE FIRE
SHOULD NOT BE EXTINGUISHED EXCEPT BY SHUTTING OFF
THE FLOW OF ESCAPING PROPANE.
It is important that we extinguish the gasoline fire by using foam, dry
chemical or water spray and at
the same time cooling the propane cylinder
with hose streams to prevent a BLEVE
Propane components in the engine compartment normally consist of the
1. The Automatic Shutoff Valve.
2. The Vaporizer-Regulator.
3. The Mixer or Carburetor.
4. The connecting high pressure hose.
If a propane leak or fire occurs in the engine compartment, it can be
controlled by ?
stopping the engine AND shutting off the supply valve on the
Remember, even though the supply valve has been shut
off, the fuel line still contains propane. It will take a period of time for the
leak or fire to stop, depending on the size of the fuel line and leak.
The fuel shutoff valve on a propane fuel tank can be turned off by turning it ?
In a propane fuels vehicle the fuel line will be identified how ?
A. The fuel line will normally be stainless steel wire braid reinforced hose
however, it could be copper tubing.
B. If the fuel line from the fuel tank to the automatic shutoff valve should
develop a leak, shut off the fuel tank valve. If gas is being released and
cannot be shut off with the tank valve then what is done ?
a fog stream of water directed at
the point of the leak will disperse the gas
The Tank Area
A. This area will vary depending on type of vehicle. The tank might be
mounted in the trunk, under the skirt of a van school bus mounted to the
frame or in bed of a pick up truck.
Agree or Disagree
If the tank area of a propane ruled vehicle is involved in a fire, immediately locate what ?
where the tank
relief valve discharges and keep clear of this area
The discharge point of the relief valve on passenger cars that are propane fuled are positioned ?
WITHIN 45 degrees of vertical. This could be located on **TOP of the trunk** or
in the ** Rear quarter panel** or possibly ** off the rear bumper**
If you cannot find the discharge point of the relief valve on the exterior of
the propane fueled vehicle,
under cover of water fog open the trunk to get at the fuel tank,
then turn off the supply valve and apply water to the container
When the discharge point is on the exterior of the vehicle, away from
where the trunk can be opened, then you can open the trunk to either turn
off the supply valve or apply water to the container depending on the
situation you have encountered.
Agree or Disagree
Identification number ______ in the
diamond indicates that compressed natural gas is being used for propulsion
The Brooklyn Union Gas Company, in conjunction with the Command Bus
Company of Brooklyn, has been running a pilot program using CNG fueled buses
since 1987. How many cylinders will be found on a the bus ?
Each cylinder contains 1100 cubic feet of gas and each bus
carries nine (9) aluminum cylinders
Brooklyn Union Gas (BUG) operates 200 dual fueled vehicles (sedans, vans or
trucks). Most vehicles are gasoline - CNG combinations. A small number are
diesel - CNG or CNG only. Each vehicle carries how many cylinders ?
from one to four CNG cylinders
Natural Gas is Heavier or lighter than air ?
CNG - is pressurized in cylinders up to a pressure ______ PSI.
CNG cylinders are protected with a fusible plug pressure relief device which will
a cylinder is exposed to heat or fire.
A big problem with CNG cylinders is a BLEVE
True or False
CNG cylinders are subject to failure, but not to BLEVE's (Boiling Liquid
Expanding Vapor Explosion) because they do not contain liquid.