LPG GAS INCIDENT

A LPG Gas Incident is classified as a Dangerous Substance Incident, therefore the notes covering a D.S. incident are appropriate. However, with the prolific use and road transport of LPG in our community, it is fitting that additional notes are included.

TURNING OUT

In addition to the standard turn out procedure the OIC of the first responding appliance should consider the level of response according to the Initial Response Plan.

Initial Alarm Response

Special Fire Contingency:

• Large LPG/fuel tankers and rail cars 2nd Alarm
• Hazardous loads - semitrailers etc. 2nd Alarm

NOTES

• The CFS has an established operational aim to have the first responding brigade to be mobile to a Dangerous Substance Incident within 3 minutes of the alarm being raised.
• If the Brigade or Group becomes aware that a Brigade is not able to raise a crew to respond to an incident as above, then it must ensure the next nearest Brigade is responded. NB It is the Aldgate Brigade?s policy that - 3 persons is a minimum crew.

ON ARRIVAL AT THE INCIDENT

• Position the Appliance Appropriately
• Upwind to avoid vapours. Also be cautious of wind changes.
• Uphill as LPG is heavier than air and will drift downhill and gather in depressions.
• At a safe distance from the incident. NB It is not uncommon for large LPG containers that explode, to send fire balls out to several hundred metres in diameter and to propel container pieces up to 1 km, deaths have occurred to persons from burns as far as 75 metres and from propelled objects to 200 metres.

• Transmit a basic/brief SITREP to the Brigade, Group, Region 1 HQ or State HQ.

• Size Up the incident.

Points to consider..

• What is the nature of the incident?
• Are there any casualties?
• Is there a fire or a threat of fire?
• Are there any exposures and what are they?
• Estimated size of the container?

• Transmit a detailed SITREP and request for additional resources, if required (also further detailed SITREPs should be sent every 30 minutes thereafter).

• Evacuate immediate area firstly up to 50m, then 200m, get the Police or other brigades to assist if needed.

• Eliminate all possible sources of ignition (ie smoking).

OPERATIONAL PROCEDURES & SAFETY NOTES

Spill Or Leak Non-Fire Situation

In addition to the action on arrival at the incident, the following procedures are to be followed...

• Stop the leak if possible (ie turn the cylinder off or utilise the Emergency Stop handle)
• If possible, separate leaking container and stand so that only gas escapes.
• Spray water to disperse gas cloud but avoid playing water directly on leaking container as this will increase leakage. Branchmen should have the protection of a further fog branch alongside them so as to give protection in case of ignition of a vapour cloud.

Fire Situation

When an LPG tank is involved in fire, there are important conditions which must be considered...

• Do the flames contact the tank shell itself?
• If not, there is no immediate risk of fire at the tank. Generally, radiant heat alone will not overheat the shell of the tank!
• If the flames actually contact or impinges on the tank shell itself, determine the liquid level in the tank from the frost line. If the flames impinge below the liquid level, there will be a pressure buildup of vapours and the relief valve will operate

with possible ignition. It will be necessary to cool the tank shell above the liquid level to reduce internal pressure and reseat the valve. Also cool the tank at the point of flame impingement to reduce the possibility of tank shell failure.

• If the flame heats the shell above the liquid level in the tank a serious condition can develop quickly!
• Flames impinging above liquid level will cause shell to overheat and bulge.
• The shell must be kept cool by playing solid streams of water over the top of the tank while staying at as safe a distance as possible.
• Use hand held hose lines until a long range monitor nozzle can be set up.
• Approach the tank from the sides and not the ends. A rupture will usually start at the bulge and continue around the tank - both ends may rocket away with great violence or the tank may rupture at the vapour-liquid line and open up horizontally, so keep as far back as possible and work from behind cover.
• Begin cooling as early as possible and fan straight streams of water back and forth over the tank.

Water Application

• The ideal method of applying water is to fan a long range solid stream on top of the surface of the tank from the opposite sides. The water will run down the sides and much of it will follow the metal surface around under the circular bottom.
• If the metal shell has been exposed to smoke and flame for a time prior to the water application, soot may hinder uniform water films on the surface of the tank.
• If the shell is heated over 212^o F., steam will form...
• there is no risk of the shell bulging and rupturing , if the metal?s temperature does not exceed 800^o F.
• because the shell is made of ductile steel, there is no risk of the shell failing because of the water being applied directly onto hot metal.
• Solid stream monitor nozzles should be used at maximum effective range...
• a course spray from the break-up of the solid streams will cool the tank.
• use auxiliary fog streams to protect nozzle men at the monitors.
• It is HIGHLY IMPORTANT that the streams of water be played back and forth on the ENTIRE top surface of the vessel to gain uniform cooling...
• if the vapours, which ignited at the relief valve diminish, good cooling is being accomplished.
• as good cooling becomes evident, nozzles should be adjusted to fog and an approach to the tank can be started. Continue to fan the tank with water.
• as control is gained, a closer approach can be made and 30o fog nozzles should be used to obtain best cooling.

final stage consists of moving in with a wider fog protection, size up and prepare to shut of the source of the fuel. If this cannot be done, cooling of the tank should continue until the fuel burns itself out.

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