When you cook on a gas stove, it’s not just heat and steam coming off those burners. The combustion process releases nitrogen dioxide and carbon monoxide into your kitchen air. And those gases don’t just hang around harmlessly — they build up in an enclosed space pretty quickly.
Nitrogen dioxide is hard to detect because you can’t smell it, but it’s a respiratory irritant that’s especially rough on people with asthma or other lung conditions. Carbon monoxide is even more serious — it’s the colorless, odorless gas that can be deadly at high concentrations. The American Lung Association specifically flags gas ovens as more likely sources of carbon monoxide and gas leaks compared to electric stoves.
The fix is simple. Run your exhaust fan every time you cook. Not just when something’s burning — every time. Washington State’s Department of Health puts it plainly: a fan that exhausts to the outside is critically important for removing the harmful gases and particles that cooking produces, including just from lighting the burners in the first place.
The key word there is *exhausts to the outside*. Some range hood fans just recirculate air back into your kitchen through a filter, which doesn’t actually remove gases — it just moves them around. If you’re not sure what type yours is, check whether there’s a duct going through the wall or ceiling. If there isn’t, opening a window while you cook is your next best move. Harvard Health recommends both — exhaust fans and open windows — together.
Also worth knowing: never use your gas stove or oven to heat your home. That’s a fast way to spike carbon monoxide levels dangerously. And carbon monoxide alarms aren’t optional if you have gas appliances — they’re cheap, and they’re the only way to catch a problem you literally cannot see or smell.