Incident Overview

A barbecue grill supplied by a 20 pound portable propane cylinder has developed a leak at a loose connection and has ignited.

The tank is being heated by direct flame impingement from the fire at the loose connection and has caused the relief valve to operate.

The burning barbecue grill is located next to a garage which is attached to a home. Fire is threatening to extend to the structure.





Summary of Cylinder Construction Features

Portable propane cylinders are widely used for small hand torches, barbecue grills, weed burners, space heaters, etc. They are usually refilled at cylinder filling stations and transported home and hooked up by the user.

Portable cylinder capacities range from .93 pounds to 95 pounds.

  • The .93 pound cylinders are commonly used for torches, gas lanterns, and camping stoves.
  • The 20 and 30 pound cylinders are mainly used for barbecue grills and space heaters.
  • The 20 to 95 pound class cylinders are usually of two or three piece welded steel construction.

Cylinders generally have one fitting welded in the service end of the cylinder. The fitting is threaded to a female normal pipe thread (NPT) and is raised above the surface of the cylinder. One combination service valve and pressure relief valve are installed in the fitting.





Incident Action Plan

Tactical Objectives

  1. Cool the outside of the portable cylinder protecting the shell and reduce the pressure to the point that the pressure relief valve closes and the cylinder valve can be manually closed.

  2. Protect exposures, extinguish any structural fires, and check for extension of the fire.

Methods of Extinguishment

A 20- to 95-pound class portable cylinder can be adequately cooled with 50 gallons per minute (gpm). This can be provided through a 1-1/2 or 1-3/4 inch attack line flowing 100 gpm or higher. Once the tank is adequately cooled, the internal pressure will drop and the relief valve should reset.

The primary attack crew can then approach the cylinder under the protection of handlines and manually close the tank valve. The approach should be perpendicular or opposite the relief valve discharge.

A second handline should be used as a back-up line to initially cover the approach of the crew closing the valve on the tank and to protect exposures.

Once the tank valve is closed, cooling water should be maintained to prevent reignition. The back-up crew can then shift to structural firefighting operations as required.





Additional Factors

Additional Factors to Consider for this Operation Include:

  1. Where possible, the back-up handline should be supplied from a water supply which is independent of the primary attack line in case the primary handline loses its water supply.

  2. Heavier hose streams and fire flows may be required if the fire has spread to the structure.

  3. Check for fire extension inside the building, especially between the interior and exterior wall spaces and in the attic and void spaces.

  4. Portable cylinder valves are right-to-tight, left-to-loosen. Make sure you are turning the valve off, not on. Note that many valve hand wheels are plastic or white metal and melt with flame impingement. Hand tools may be needed. Twelve inch water pump pliers will turn the valve stem when the handle is broken.

  5. If copper gas lines are damaged, crimp off the line with pliers after the cylinder valve has been closed. The other alternative is to simply disconnect the line and plug the valve opening using a POL plastic plug.

  6. Continue to cool the tank until well after the fire has been extinguished. The metal surface should be cool enough to touch.

  7. The area around the cylinder and inside the adjacent structure should be monitored for flammable vapors using a combustible gas indicator (CGI).

  8. Notify the local propane supplier and obtain technical assistance.





 Incident Map

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 Incident Video

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