More thoughts on gas stoves indoors …
I’ve been doing some more reading and listening to podcasts about the alarming news about gas stoves used indoors. It seems like most of the issue is not the short-term emissions of nitrogen-oxides, but the accumulated emissions from nitrogen-oxides in poorly ventilated, modern homes. While natural gas burns relatively cleanly, it also burns hot, which causes the nitrogen in air to fuse together, producing nitrogen oxides, which are irritating to human lungs, especially in chronic exposures. On top of it, the World Health Organization has recently, once again, slashed levels of NOx that are safe for chronic exposures.
Gas stoves are most common in higher-end suburban homes, especially those in the Northeast and along the California coast. Newer homes tend to be more air-tight, with fewer leaky areas allowing drafts to flow air in out. While some of these homes have outside vents with heat exchangers, it’s likely they do not remove or bring in enough air to keep NOx from building up in the house over time. With fewer days with people keeping their windows open due to central air conditioning, the problem is only getting worse over time.
One of those podcasts I was listening says the science shows that having a gas stove in your house is a similar asthma risk to children as having a smoker in your house. Cigarette smoke is a little different then natural gas smoke, as cigarettes tend to smolder, produce more carbon monoxide and partially burnt hydrocarbons and less nitrogen oxides. But still it’s an air quality issue, in part due to poor ventilation. But does having a smoker in one’s house mean automatically that children get asthma?
Scientists say that second cigarette smoke or natural gas cooking increases the risk of childhood asthma by 10%. But only 5.3% of children ever get asthma, so the actual increased risk of having a gas stove or second hand smoke for asthma is 0.53% or 1 in 172 households. That is problematic from a public health perspective — it means 530,000 more childhood asthma cases per year — but the relative risk to anyone child is relatively low. Despite the demonetization of the second-hand smoke or gas stoves, the risk to any one child is pretty low.
The truth is that combustion of any material in an enclosed space with humans is a bad idea. Outside where air is freely available and can mix, the byproducts of combustion are far less harmful, except in excess amounts such as air pollution in populated areas subject to air inversions caused by terrain and weather conditions. Gas stoves would be far less harmful if combined with hoods that operated when the stove was on, sucking out the toxic gases, or at least when a window is open to allow fresh air to flow in and out.
Nobody in their right mind would leave a gas-powered automobile in a garage idling with the garage door shut. Natural gas is a cleaner fuel to burn then gasoline, but it’s still a fossil fuel that produces heat and exhaust gases. And even when it’s not poisoning the air indoors, it is warming the climate both as it escapes from pipelines and is burned in stoves and furnaces. From a human health perspective, it’s far better to move the smoke from people’s kitchens to a distant power plant, preferably one that generates electricity not by burning fossil fuels but using renewables.
When I own my own land, I might have a gas range, just because for off-grid operations, there is a lot of benefit to cooking with gas. Namely, gas is a dense store of energy, it can be hauled in 20 lb or 100 lb propane tanks. But I know would want to keep a window open when cooking, and consider doing as much cooking as possible outdoors where there is fresh air. Or use the top of the woodstove for cooking. But ultimately, propane for cooking doesn’t use that much gas compared to a contemporary suburban house with gas heating, which uses and emits far more emissions then a simple cook stove. Gas for cooking usually enables gas for heating, and it’s the heating that is more significant climate problem. Suburban houses need to move away from gas heating and cooking, as we dive deeper into the climate crisis that will impact all.