We still remember the final indoor air quality test we conducted.

When we arrived at the single-family residence on the South Side of Chicago, where the owner had lived for 58 years, we were unsure of what we would find. Once we started testing carbon monoxide and nitrogen dioxide levels near the gas stove, the monitors showed something that none of us could have seen with our eyes. Even with the stove turned off, carbon monoxide levels were 14 parts per million (ppm), while nitrogen dioxide levels measured 14 parts per billion (ppb). After turning the oven and two burners on for 15 minutes, those figures rose to 89 ppm for carbon monoxide and 180 ppb for nitrogen dioxide.

Halfway through, we stopped the test. The carbon monoxide and nitrogen dioxide readings had already exceeded the U.S. Environmental Protection Agency’s one-hour outdoor standard. The EPA has found that breathing nitrogen dioxide outdoors can worsen respiratory health, including asthma. But families do not only breathe outdoor air. What are the effects when we breathe it inside?

The test was part of Faith In Place’s Air Aware project, a citizen science effort to help Chicago residents better understand the air quality inside their homes. Through St. Luke Missionary Baptist Church, we tested 10 homes among church members and South Shore neighbors, as part of a broader effort that reached 101 homes across Chicago. People let us into their kitchens, basements and living rooms. One of us helped guide the conversation with residents as the other handled the monitors, timing and readings. Together, we watched as the numbers gave people a clearer picture of something they could not see, smell or easily measure on their own.

This was not the first home where the readings raised concerns. By the time we conducted this final test, we had seen similar patterns during other visits, and other volunteer testers were seeing them across Chicago as well. As part of the test, we detected carbon monoxide near gas-burning equipment in more than 80% of homes. After 30 minutes of ordinary gas stove use, nitrogen dioxide levels in more than half of kitchens rose above 100 ppb, the threshold used in the EPA’s one-hour outdoor air standard.

Many residents knew carbon monoxide could be dangerous at high levels. But far fewer knew about the health risks posed by nitrogen dioxide or the devices that can test for it.

That’s why we need policymakers to act.

Illinois should start with clearer public education. To help consumers make informed decisions about the health risks associated with gas-burning appliances, the state should require commonsense warning labels on gas equipment that explain how gas appliances may affect indoor air quality and health. Policymakers also should provide an easy-to-access resource guide that helps households improve ventilation and take steps to reduce exposure in the short term.

Our testing also made clear that healthier homes are possible when households have access to efficient electric appliances that reduce the indoor air pollution risks of burning gas at home. Long term, Illinois should help households modernize with heat pumps, induction cooktops and other efficient electric appliances. These investments must especially reach communities already facing higher pollution burdens, particularly lower-income communities that face the greatest financial barriers to upgrades.

As we tested homes across Chicago, each visit and each conversation were a different journey. Some residents had lived in their homes for decades; others had just moved in. Some lived with children or older relatives, and some lived alone. But most were surprised by what the tests showed. Again and again, the same basic concern came up: What does this mean for my home, and what can I do next to protect my health?

That question should not be left for families to figure out on their own. Knowledge of what’s in the air shouldn’t be a blind spot. Illinois needs clear public education so all residents understand the risks before bringing gas equipment into their homes. A safe and healthy home should be a basic expectation. Illinois lawmakers, regulators and agencies should make that a reality for every household.

Carol J. Williams and Patrick Shaw are community volunteers affiliated with St. Luke Missionary Baptist Church on Chicago’s South Side, where Williams leads the church’s Green Team and Shaw is a participant. 

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