Propane may move, slide, or topple during heavy ground shaking and are potentially hazardous unless both the tank and the piping are properly secured and a flexible hose connection is used. Gas leaks are frequently the cause of earthquake-related fires. A single pound of propane is equivalent to one stick of dynamite. If a tank rolls over and explodes it could be devastating, and an unsecured tank may leak, draining a source of fuel that could otherwise be used for cooking and heating. The system shown below is an easy solution to this problem. If you prefer not to do this work yourself you can contact a contractor to anchor your tank. You may want to consider installing a Seismic Valve as well, as it would automatically shut the propane off during a quake, protecting your home and property from fire hazard and preserving the fuel in your tank for future use.
Why secure your tank? Even a minor quake can cause propane tanks to break free of their supporting legs. When a tank falls, there is always a danger of a fire or an explosion. Even when a tank remains on its legs, its supply line can be ruptured. Escaping gas can then cause a fire. Similar problems can occur with smaller, unsecured compressed gas cylinders stored inside a house or garage.
A fire caused by earthquake damage is a true emergency. Resources to fight fires may be spread out and access to a fire area may be limited or blocked. Water sources will likely damaged and water unavailable.
Make sure the members of your family know how to immediately turn off the supply line at the tank and inspect for gas leak. If you lease your equipment contact your propane provider before making modifications, such as providing a flexible connection between the propane tank and the supply line and where the supply line enters the house, and installing a seismic shutoff valve on larger tanks that will automatically turn off the gas during an earthquake. These installations should be done by a licensed contractor. In the image at left, Dan Harvey demonstrates tank strap installation during the JEPP-Sponsored October 2017 Joyce community emergency Fair and explains the importance of taking this step for homeowners and businesses.
When securing small vertical tanks of 120 gallons or less, use two lengths of strapping, one just below the top of the cylinder and one just above the bottom of the cylinder. In wooden walls, attach straps to eye hooks that are long enough to penetrate not just the wall but the studs behind it as well. When securing larger tanks of 120-1000 gallons, use straps that are a minimum of 1.25” wide x 0.035 inches thick and made of zinc-coated galvanized steel, and strap sheathing to protect the tank’s surface. Use adjustable anchor bolts to tighten the steel strapping, either earth auger anchors (3 foot lengths are recommended for our class of soil), or concrete expansion bolt anchors to secure to concrete pads. If securing to concrete or masonry block walls, the eye hooks should be installed with expansion anchors or molly bolts.