I get many calls from customers with concerns regarding a gas odor coming form their gas oven or gas dryer. It is true a gas leak will give a gas odor. However, that is not as common as one other “Gas Smell” issue. —- Natural gas has additives which give it the tell-tale sulfur odor. These additives normally burn away in the combustion process. However, impurities (especially chemical impurities) can impede the natural combustion process and allow the additives to be released without burning away. This “Emission Odor” gives a false “Gas Leak” assumption.
One way to differentiate between the two types of odors is; a gas leak is normally present when the appliance is dormant (not in use). An emission odor is present only when the appliance is in use.
The most common causes of Emission Odor is from paint or varnish fumes in the home (though it can be caused by any number of sources). If you have one appliance that smells of a gas leak, consider if you have recently (within the last few months) done any painting or varnishing in your home. If so, you may not have a gas leak, but an Emission Odor. If it is caused by chemical fumes in your home, you can go to other gas appliances and they should be emitting the same smell because the chemical fumes would be present within the entire home. If the odor is localized with one appliance only, you may indeed have a gas leak.
Remember, it is always best to call the gas company, or a qualified service tech to assess your situation if you have a gas smell in your home. However, as I mentioned, many (if not most) gas odors I have encountered in a customer’s home have not been gas leaks, but Emission Odors.