With gas cooking, as compared with electric cooking, more chemical combustion products are being released into your home. This is because of the way heat is generated with gas — there’s ignition and a visible flame, which represents the combustion (burning) of the organic fuel (gas) right there in the home. With electric cooking, the combustion happens far away, at a power plant or some other offsite energy source, to create the energy that generates heat.When combustion occurs in your home, more products of that combustion — ultrafine particulate matter and gases such as methane, harmful nitrogen oxides or even deadly carbon monoxide — are released into the indoor air if the gas appliance isn’t ventilated properly.The leakage that’s been detected in some gas stoves/ovens can happen wherever there’s a natural gas utility connection in the home, sometimes at the stovetop or oven itself. Older appliances that aren’t as well-maintained may have undetected or slow gas leakage, and gas combustion when cooking or baking may be less efficient. Without proper local exhaust ventilation, such as a kitchen exhaust fan, or sufficient overall general ventilation, ultrafine particulate matter and harmful gases may accumulate.