3 signs your kitchen has high levels of Nitrogen dioxide

After years of helping people troubleshoot indoor air problems, I’ve noticed that kitchens are often overlooked when people think about air quality. If you cook with a gas stove, nitrogen dioxide (NO₂) deserves particular attention.

Three clues I tell customers to watch for:

1. A noticeable drop in air quality after cooking
If the kitchen feels stuffy, irritating, or unusually unpleasant during or after using the gas burners—especially without good ventilation it’s worth paying attention to.

2. Persistent irritation around cooking time
Some people notice eye, nose, or throat irritation when cooking with gas. These symptoms aren’t proof of high NO₂ by themselves, but they’re a good reason to improve ventilation and investigate further.

3. Your NO₂ monitor repeatedly rises during cooking
This is the most useful sign. A properly placed indoor air monitor can show whether NO₂ consistently increases when the gas stove or oven is running.

One lesson I’ve learned over the years: you can’t reliably judge NO₂ by smell. It’s an invisible pollutant, so ventilation matters even when the kitchen seems perfectly normal.

If you have a gas stove, use the range hood whenever possible and make sure it actually vents outdoors. A little ventilation during cooking can make a surprisingly big difference.