Hazmat Chap 1- Alternate Fuels Flashcards
LP…
liquefied petroleum gases -stored as liquid under pressure -vaporize as gas -referred to as "bottle gas" -odorless -flammable HEAVIER than air(1.5 - 2 times)
Basic precautions at LPG Gas Fires/Emergencies…
approach fire/leak from UPWIND
- keep nozzle low and aim upwards
- clear out persons in vapor cloud
- evacuate person in path of vapor cloud immediately
- shut off all sources of ignition at the SAME TIME
Everyone, NOT ACTUALLY ENGAGED in operations…
at least 1000 feet from the front and rear of the tank
and
500 feet from the sides
Do not extinguis the fire until the leak has been stopped…except…?
Under extremely unusual conditions
If only valve that can be used to stop flow of gas is involved in fire or exposed to heat or flame…consider?
using a HEAVY FOG STREAM to protect member while he shuts valve
- proceed SLOWLY to prevent flashback
- wear masks and protective fire clothing
Tanks surfaces exposed to heat, either from auto exposure or fire from another source…can be protected by…?
applying LARGE quantities of water on them
Where escaping gas is on fire and flow cannot be shut off, application of large quantities of water on the tank and piping will permit CONTROLLED BURNING..
allowing fire to consume the CONTENTS of the tank, without danger of tank or or pipe failure…make certain…fire is NOT EXTINGUISHED
What is effective on small LP gas fires?
PORTABLE DRY CHEM
applied at BASE of the fire
CARBON DIOXIDE EXTINGUISHERS CAN ALSO BE USED
-tank failure usually occurs in VAPOR area
Before tank failure occurs, rise in pressure will cause an …
INCREASE in the volume of fire or rise in NOISE LEVEL, or both…may or may not be accompanied by a bubble or blister forming on tank shell
ANY of these symptoms present, OPERATING forces should be withdrawn to safe area
Normally no attempt should be made to move a tank involved in fire….HOWEVER
It conditions develop that make it desirable to move tank, it should be moved in an UPRIGHT position
-NEVER drag it in a manner that might further damage valves or piping
-PORTABLE LP GAS CYLINders exposed to a serious fire should be removed to safe location
LP Gas LEAK WITHOUT FIRE…
- close ANY valve available to stop flow of gas
- small lines (copper tubing) can be flattened to stop flow
- vehicles involved- consult driver
- storage facilities- consult plant personnel
Is water spray effective in dispersing LP gas vapor?
YES…used as soon as possible..disperse vapor to safe location
- avoid entering vapor cloud
- keep low behind spray/protected from radiant heat
if water spray is not effective in dispersing LP gas vapor, then heavy streams of water from safe distance
Propane fueled vehicles
- mostly dual-fueled vehicles-GASOLINE AND PROPANE
- buses/vans/autos
- signs or placards to identify
- finding a PROPANE CYLINDER is a positive means of identification
- Propane is an LPG
Propane…
- liquified gas stored in cylinders at temp above its boiling point -remains under pressure as long as container remains closed
- heat applied in the cylinder will cause excessive pressure to build up in the cylinder opening the relief valve
- cylinder involved in fire can ‘BLEVE’
- 1 cubic ft of liquid will expand 270 times as a gas
impact failure of a cylinder in a transportation accident can also cause a BLEVE
BLEVE in propane will result in explosion/fireball with cylinder becoming missile
Leaks/Spills…
- eliminate sources of ignition
- evacuate immediate area:down wind/low areas (cellars), where life hazard greatest
- use fog streams
- control leak
- utilize combustible gas detector
