Food brings friends together. Since the dawn of mankind the act of sharing a meal has been a focus of a tribe or family. The modern bbq has the honour of being the modern day equivalent. Since the widespread adoption of the gas fuelled bbq, many myths have abounded popularised by rare yet widely publicised, stories of explosions, fire and injuries.
A commonly held belief is that if you can smell gas then an explosion is imminent. It is possible yet generally unlikely. With some understanding of the characteristics of LPG a more realistic and measured approach can be applied to using this gas safely.
LPG is liquefied petroleum gas commonly known as propane (C3H8), a combustible hydrocarbon based fuel. However, most LPG is a mix of propane and butane depending upon the refinery and time of year of when the gas was produced. LPGis a by-product from the refining of crude oil and natural gas. At normal pressure and temperatures above -44F/-42C Propane remains in its gaseous form. At lower temperatures and/or higher pressures propane/butane will become a liquid. LPG is flammable between 2% and 9% concentration in air. That’s a very narrow flammability range. Have you ever tried to light your gas burner atop your stove and had what seems like gas pouring out at an alarming rate and your stove’s piezo clicking and sparking away but the gas still wont ignite?That’s because the gas is too rich to burn. Yet you can smell that awful gas odour. Propane and butane gasses are actually odourless. The smell we associate with gas is actually mercaptan or methyl mercaptan, which is actually added to the LPG to give it a detectable smell. The mercaptan compounds are detectable by the human nose at concentrations of only 10 parts per billion. In plain English that means that we can smell a LPG gas leak before it even reaches .01% of its lower flammable limit.
What should you do?
Avoid cooking a barbecue in a confined area. Open the garage door if you intend to use the garage for your venue. Check your hoses for cracking or fatigue. Check that all fittings and fixtures are firm and if in doubt check for leaks with some soapy water and a brush, or use a spray bottle or pump pack to apply soapy water to hoses and fittings. It is a rare occurrence for an explosion to originate from the humble barbeque but with some care and common sense it may never become a serious concern.
-Scott Eggenton
Scott is a barbecuing aficionado and former butcher whose passion for bbq-grilling of good food and sharing it with good friends has led him to invite the world to join him at www.greatbbqgrillrecipes.com