Nitrogen dioxide (NO2) is a highly reactive gas that is created from the combustion process of vehicles, power plants, gas stoves, and kerosene or butane heaters. It is also a byproduct of welding and tobacco smoke.
Nitrogen dioxide has a distinct acrid smell so it is generally easy to avoid exposure. However, low concentrations (4 parts per million) can anesthetize the nose, so a person may be unaware of the chemical’s presence.
Nitrogen dioxide is a common pollutant both indoors and outdoors. It contributes to ground-level ozone and fine particle pollution and can cause serious damage to the lungs. Initial exposure to will irritate the eye, nose, and throat. Higher concentrations or prolonged exposure can impair lung function and cause respiratory infections.
Intense exposure to high concentrations (such as in a building fire) can result in lung injury and pulmonary edema (fluid in the lungs because the heart cannot pump adequately). Continued exposure at moderate levels can lead to acute or chronic bronchitis. Even low levels of exposure can cause asthma attacks, decreased lung function, and respiratory infections.
Because both nitrogen dioxide and carbon monoxide are created in combustion processes, the steps to reduce indoor exposure are the same for the two chemicals. The Environmental Protection Agency lists the following steps to reduce exposure:
- Keep gas appliances properly adjusted.
- Consider purchasing a vented space heater when replacing an un-vented one.
- Use proper fuel in kerosene space heaters.
- Install and use an exhaust fan vented to outdoors over gas stoves.
- Open flues when fireplaces are in use.
- Choose properly sized wood stoves that are certified to meet EPA emission standards. Make certain that doors on all wood stoves fit tightly.
- Have a trained professional inspect, clean, and tune-up central heating system (furnaces, flues, and chimneys) annually. Repair any leaks promptly.
Do not idle the car inside garage.