The gas that we use every day to heat a room, cook a meal, barbecue steaks, supply hot water or propel our lawn mower can cause smoke, fire, and poisonous fumes if equipment and appliances are not maintained.
Among the most lethal dangers are natural gas and propane explosions, whether they result from defective appliances or grills, faulty lines or vents, or overheated or leaking cylinders and tanks.
Natural gas is used in an estimated 65 million homes in the U.S. to fuel gas furnaces, gas stoves, water heaters, and the like.
Natural gas is touted as one of the safest and cleanest burning fossil fuels; when operating properly, gas produces water vapor and carbon dioxide and fewer greenhouse emissions than wood, coal, or oil.
- Natural gas comes to us through miles of pipelines that extract hydrocarbons from the earth, remove impurities and transport it primarily as methane gas. It is this methane gas that is most commonly used for household purposes, and generally it is quite safe.
- But because gas is highly combustible, a gas leak could cause an explosion that burns down a house or emits fumes that deprive you and your family of oxygen and could lead to unconsciousness or even death.
- When natural gas does not burn properly or completely because of faulty installation or lack of ventilation, it gives off a byproduct of carbon monoxide (CO). Carbon monoxide poisoning is especially life-threatening because it is odorless, colorless and tasteless – and it kills thousands of people each year.
- You can minimize the risk of using gas in your home by providing adequate ventilation and installing a natural gas detector and a carbon monoxide detector that will signal an alarm if gas levels exceed the safety threshold.
Speaking of carbon monoxide poisoning, you might want to learn additional information about how it is generated, what the symptoms are, and how it can be prevented. As the Center for Disease Control and Prevention points out, all CO poisonings are preventable.
Carbon monoxide is generated by the gases discussed on these pages, and also by the petroleum (gasoline) that we use in motor vehicles. Common causes of CO poisoning are cars left running where fumes seep into the garage or house; portable generators; water heaters and other gas appliances; and space heaters, camp heaters and camp stoves.
- Carbon monoxide (CO) is not to be confused with carbon dioxide (CO2), which we breathe out, is in our bloodstream, and is used by plants for the photosynthesis that makes them grow. Carbon dioxide is not poisonous unless inhaled in large quantities. It is used in numerous commercial processes, such as carbonating beverages and, in solid form, for dry ice.
- CO is produced whenever any fuel – gas, oil, kerosene, wood, charcoal – is burned. If the fuel-burning appliances are working properly, the small amounts of CO produced are not dangerous. But when inhaled in larger amounts, CO can be fatal to humans and to animals.
- According to the Centers for Disease Control and Prevention, at least 400 people die each year from unintentional CO poisoning and another 20,000 seek emergency treatment, 20% of whom are admitted to hospitals. Infants and people over 65 or with heart or respiratory conditions are especially susceptible to CO poisoning.
- Symptoms of CO poisoning include headache, confusion, fatigue, seizures, dizziness, nausea and loss of consciousness. Sometimes victims slip into unconsciousness and never awake; others may be already asleep and never wake up again, as when CO fumes seep into bedrooms from a car left running in the garage.
- Long-term effects of CO poisoning include brain damage, heart problems, major organ dysfunction, memory or cognitive problems, behavioral and personality changes, and a range of other permanent damages.
Read further to learn how to prevent CO poisoning in common situations with household appliances and other devices fueled by CO-generating gases. You will find that one of the best protections is to install a CO detector in your home, and to seek immediate medical attention if you are suffering some of the symptoms.
Propane, or liquefied petroleum (LP), is commonly used for home heating. Large propane tanks often can be seen next to a house with a gas furnace, gas fireplaces or an emergency gas generator. Smaller cylinders of propane are used with gas barbecues, camping stoves, camp heaters, and lanterns.
But propane is both highly flammable and odorless – a risky combination. Often, ethanethiol, which has a strong odor that smells like rotten eggs, is added to propane so that leaks can be detected. Symptoms of propane poisoning include nausea, fatigue, shortness of breath or dizziness and can lead to death.
If you should experience a propane leak, get out and away from the area, DO NOT SMOKE, and do not use anything with an open flame or anything that generates a spark, such as a telephone or cell phone. If it is safe to do so, shut off the gas valve and call the propane dealer. Your safest bet is to dial 911.
Another danger is posed when the pilot light of a gas stove or other appliance goes out. The pilot light normally has a continuous flame that ignites the main burner when you turn the knob on your stove. If the pilot light itself goes out, gas accumulates in the area and threatens fire, explosion or carbon monoxide poisoning. If you smell gas, do not attempt to relight the pilot light yourself; call a repair person.
Propane tanks must have ventilation and should not be stored in enclosed or very warm areas. Take care to place tanks away from grills and hot appliances, and not in the trunk of a car where overheating could cause combustion. Similarly, transporting propane tanks requires care: Keep them in an upright position and make sure they can’t tip or roll; never transport propane tanks in the trunk of a car.
Most important, old and damaged propane tanks should not be refilled or reused. Portable cylinders are required to be inspected regularly and stamped with the inspection date, and a cylinder may not be refilled if it has expired.
Propane cylinders used in barbecuing are a frequent source of propane explosions due to defective grills, faulty lines or vents, and overheated or leaking cylinders. But even if the grill and its components have been well maintained, cylinders themselves may be leaky or out of date. You should always buy from a reputable propane dealer and check with that dealer about where, when and how to refill or exchange for new ones. Beware of buying so-called used or refilled cylinders from someone you don’t know – they may have dangerous leaks obscured by fictitious date stamps and other cosmetic alterations.
Here are some safety guidelines for grilling with propane from the Florida Propane Gas Safety, Education and Research Council:
- Always grill outdoors, never in an enclosed space. Place your barbecue away from leaves and brush, as well as your home and garage. Keep cylinders upright and don’t store spare gas containers under or near the grill. Close cylinders completely when they are not in use. Never attach or disconnect a cylinder when the grill is in operation or is still hot.
- Have cylinders checked for dents, rust or leaks when you are having them refilled. If a cylinder has any of these things, discard it and get a new cylinder. And make sure your vehicle is well ventilated when you transport cylinders to and from your propane dealer.
- When you are not using your grill, cover disconnected hose fittings and burner air intakes with protective caps to keep out dirt, moisture and insects. Check grill hoses for corrosion and kinks in the tubing, and use a wire or pipe cleaner to clean out tubes that lead to the burner.
- You can purchase leak detection solutions from your propane dealer that help you find leaks before igniting your grill. Before igniting, check to make sure connections are tight. If you smell the propane gas, turn off the gas right away and do not proceed with ignition.
Floridians may be especially interested in propane safety guidelines to implement in case of an emergency such as a hurricane. The following are safety tips from the Florida Propane Gas Safety, Education and Research Council.
- When you first are alerted to an approaching storm, secure your propane tank if possible, but never bring it indoors. Turn off the gas valve and fasten the tank’s protective dome.
- Turn off appliance pilot lights, control valves and manual shutoff valves. Be sure there is a sufficient fuel supply in the tank.
- After the storm has passed and normal conditions prevail, be on the alert for signs of damage that will require a propane dealer or qualified technician for repair. These might include propane tanks that have shifted or moved; visible tank damage; broken or bent gas lines; and tank regulators or appliance controls that have been exposed to water.
- If you evacuated the premises without turning off your propane tank, turn it off immediately upon returning, before turning on electric service or using any device that could generate sparks or flames.
Outside the home, there are still more dangerous sources of poisonous and explosive gases.
- On boats, carbon monoxide from generators or engine exhaust can build up inside and outside the boat. A National Park Service investigation in 2000, aided by the U.S. Coast Guard, evaluated visitor and employee CO exposures from generators and propulsion engines on houseboats at Lake Powell, California. Since then, additional studies have been conducted of recreational boats, ski boats and personal watercraft.
- The investigation’s initial findings showed high concentrations of CO on and around houseboats using gas-powered generators. Further research identified more than 800 boating-related CO poisonings in 35 states, 140 of them fatal. More than 300 of these poisonings occurred on houseboats; two-thirds were traced to generator exhaust alone.
- On land, burning gas fumes constitute a significant health risk for gas-powered go kart drivers who are exposed for long periods of time. Gas-powered go karts generate two or three times the amount of pollution generated by electric karts, making it impossible to use indoor race tracks for gas go kart events.