Yes, a gas leak smell can absolutely come and go. Because natural gas is naturally odorless, utility companies add a chemical called mercaptan, which smells like rotten eggs or sulfur. This smell can be intermittent for a few reasons:
Smells that resemble a gas leak (rotten eggs or sulfur) but aren't include sewer gas from dry drains, bacterial growth in water heaters, old batteries, or specific household chemicals. Other causes include mold, dead rodents, or a malfunctioning furnace exhaust.
The smell of spilled gas can dissipate in just a few hours on a sunny, breezy day on a hard, non-porous surface. However, if the fuel has soaked into porous materials like concrete, clothing, or car upholstery, the odor can linger for several weeks to a few months without proper cleaning or ventilation.
Natural gas is naturally colorless and odorless. To make leaks detectable, gas companies add an odorant called mercaptan, which creates an unmistakable, pungent stench similar to rotten eggs or a sulfur-like smell.
If you smell gas but cannot find a leak, the odor is likely caused by a minor appliance issue, such as a malfunctioning pilot light or a small amount of unburned gas passing through a burner. Other causes include the odorant (mercaptan) itself or a very small leak that has evaporated.
The smell of "gas" usually refers to either the rotten-egg odor added to natural gas and propane, or the sharp, pungent chemical scent of vehicle fuel.
A gas leak goes unnoticed for hours or even days if no one is home or awake to notice the signs. Small leaks escape slowly and make it harder to detect without regular checks. That's why simple habits like paying attention to strange odors or hissing noises protect a property from silent risk.
Yes, even a small gas leak can make you sick. Natural gas reduces the amount of oxygen in the air, causing symptoms like headaches, dizziness, nausea, and fatigue. For safety, leave the area immediately without turning on lights or switches, and call your gas provider or 911 from outside.
Most leaks occur at utility pipelines, but leaks occasionally happen in residential areas, including in-home leaks. The best thing you can do to keep your home safe from in-home leaks is to maintain your gas-powered appliances well and call for repairs right away.
Carbon monoxide (CO) is an odorless, colorless gas that can cause sudden illness and death if inhaled.
A gas leak smell is typically very strong, distinct, and unmistakable. Because natural gas is naturally odorless, utility companies add a chemical called mercaptan, which is engineered to be incredibly potent.
If you suspect you're dealing with a gas leak in a house, take the following steps: Evacuate the premises. Everyone in the home should leave the building immediately and regroup at a pre-chosen safe place.
Some of the hardest and worst smells to get rid of are pet odours, mold, and cigarette smells.
Performing a DIY gas leak test safely and easily relies on the "soapy water" method.
Because natural gas is naturally odorless, a foul-smelling sulfur compound called mercaptan is added to it. If you smell something resembling rotten eggs, sulfur, or a skunk, the scent usually comes from one of the following sources:
No, a standard carbon monoxide detector will not detect a gas leak. They are specifically calibrated to detect carbon monoxide, which is a byproduct of combustion, rather than explosive gases like natural gas (methane) or propane.
The first signs of a gas leak usually involve a distinct rotten egg or sulfur smell (due to an added odorant), a persistent hissing or whistling sound near gas lines, or physical symptoms like sudden dizziness, headaches, or nausea.
Toxic gases do not all smell the same. Many are entirely odorless, while others are intentionally given a smell or have a naturally sharp, pungent odor.
Early detection of natural gas leaks can prevent potentially catastrophic incidents. Firefighters should be trained to detect the telltale odor of gas and to use gas detection monitors to identify the presence of leaks.
Symptoms of carbon monoxide poisoning include:
Carbon monoxide is called the silent killer. You can't see it or smell it, but it can make you very sick or even be deadly. This November, take simple steps to protect your home and family: Check your CO detectors, inspect appliances, and never use generators or fuel-burning tools indoors.
How long does it take to get carbon monoxide poisoning? In high concentrations of carbon monoxide, it can take fewer than five minutes to get carbon monoxide poisoning. Under lower concentrations, it can take an hour to two hours to cause poisoning.
What common household smells can be mistaken for a gas leak? Sometimes mold, rotten eggs from food, or sewer smells can confuse you. Gas leaks have a distinct rotten egg or sulfur smell added by gas companies.
No, a faint smell of gas is never considered completely normal or safe.
At least 430 people in the United States die of unintentional carbon monoxide poisoning every year. And 50,000 people visit the ER for accidental carbon monoxide poisoning annually [source: CDC]. Unvented space heaters are the most common source of carbon monoxide poisoning [source: Johns Hopkins Medicine].