Natural gas heating and cooking are coming under more scrutiny, especially their negative impact on indoor air quality. In particular, nitrogen dioxide (NO2) emitted from gas stoves and furnaces aggravate childhood asthma. The issue has been obvious for years but is now getting renewed attention of regulators.
Gas heating and cooking are popular throughout the United States and Europe. One estimate is that a third of U.S. homes use natural gas for cooking, which has been promoted for decades as a “clean” alternative.
Need for Indoor air regulation
The U.S. Environmental Protection Agency (EPA) has the authority to regulate outdoor air, but not indoor. The Consumer Product Safety Commission (CPSC) has jurisdiction over performance standards of consumer appliances but does not view gas ranges as a “significant contributor” to adverse air quality or a health hazard. (CPSC says they are “aware of recent studies.”)
Building codes require that gas furnaces and water heaters be vented outside, but there are fewer requirements for ventilation of natural gas cooking stoves.
Negative impact on health
As awareness grows of the negative impacts on indoor air quality, gas cooking and heating will be targeted by regulators
As awareness grows of the negative impacts on indoor air quality, it is more likely gas cooking and heating will be targeted by regulators.
Natural gas-burning stoves and furnaces produce an array of pollutants with adverse health effects, including particulate matter, nitrogen dioxide (NO2), carbon monoxide (CO), and formaldehyde. If a massive transition away from natural gas becomes likely, there are opportunities for the HVAC market.
Removal of gas appliances
Recent research has helped to focus media attention on the issue, including reports from the Rocky Mountain Institute (RMI) and the UCLA Fielding School of Public Health. Older research was highlighted in a 2013 analysis of 41 studies on the subject, showing that children living in homes with gas stoves had a 42% higher incidence of asthma symptoms.
The COVID-19 pandemic’s trend of staying and cooking at home has exacerbated the problem. Long-term exposure to elevated NO2 has also been correlated with a higher risk of COVID-19 death, according to an Emory University study. Because of the risks, the New England Journal of Medicine published an editorial recommending that new gas appliances be taken off the market.
Switching to electrical appliances
Around 40 cities and towns in California have adopted ordinances to require all-electric appliances
California is the first state to address the health threats of gas appliances. In the Golden State, about two-thirds of homes rely on gas as the primary cooking and/or heating fuel.
The California Air Resources Board (CARB) has proposed that a statewide transition to electric appliances would provide substantial health benefits. CARB also supports better ventilation standards. Around 40 cities and towns in California have adopted ordinances to require all-electric appliances in new residential buildings.
Indoor pollution and high prices
Older homes and lower-income households are especially at risk. The UCLA research emphasizes that smaller spaces housing more people and with poor ventilation are more susceptible to higher levels of indoor pollution. Unvented gas-burning space heaters (which are illegal in California) can be even more dangerous than stoves because they tend to be used for longer periods.
Another trend that could impact demand for gas systems is the rising price of natural gas, now 99% higher year-to-date. The price is expected to continue going up and could double again if there is a cold winter. More consumers may be looking at alternatives, including electric heat pumps – more opportunities for HVAC professionals.