Stoves and Ovens Emit Indoor Air Pollutants

Indoor air pollutants given off by stoves
Indications of a problem
Preventing IAQ problems from stoves

Indoor air pollutants Given Off by Stoves

Most of the problems associated with stoves are the pollutants that may be given off by inadequately vented gas ranges, including:

• Carbon monoxide

• Nitrogen dioxide: In homes with gas stoves, indoor levels of nitrogen dioxide may exceed outdoor levels.

• Sulfur dioxide

• Particulates

• Combustion pollutants

• Polycyclic aromatic hydrocarbons (PAHs) are organic particles and gases. One study showed that a home's level of PAHs rise when residents fry, sauté or broil food. PAHs, which are not found in the food itself, are formed by the combination of burning fuel and burning cooking oil during frying.¹

Because of these pollutants, those who live in a home with a gas stove are more than twice as likely to have breathing problems than those who live in homes where electric stoves are used.²

In addition to these pollutants, both gas and electric stoves contribute to the build-up of moisture in the home. Cooking and dishwashing produce about one pint of water in the air per meal. This is a problem because moisture can aggravate allergies and trigger asthma attacks due to biological contaminants such as dust mites, fungi, and cockroaches that all like moist, humid conditions.

Indications of A Problem

The following are some indications of a problem with a stove:

• There is a change in the flame's color in a gas range. For example, if a blue flame becomes yellow, carbon monoxide (CO) levels may be increased. However, some blue flames produce elevated carbon monoxide levels as well, while some new appliances normally have a yellow flame.

• There is condensation or moisture on the inside of the windows. That means there is not enough ventilation.

• You smell food odors when you come into your home after being gone for several hours. This can mean that the vent over the range may not be working correctly.

Preventing IAQ Problems From Stoves

• Cover all pots when cooking to reduce moisture that could lead to biological contaminants.

• Run a ventilation fan that exhausts to the outside when cooking. A circulating fan may remove some cooking odors from the air, but it will not remove moisture.

• Only buy a gas stove that has been tested and certified to meet current safety standards. Examples of certifying organizations are Underwriters Laboratories (UL) and the American Gas Association (AGA) Laboratories. Look for a label that clearly shows the certification.

• Use pilotless (electronic) ignition on gas appliances. These appliances are usually more energy efficient and eliminate the continuous low-level pollutants from pilot lights.

• Install and use an exhaust fan vented to outdoors over gas stoves. Remove and clean the metal mesh filters on your range hoods with detergent when they begin to look grimy (most can be put in the dishwasher). "Ductless" range hoods are not effective because they exhaust into the house rather than outside; add a duct or replace the hood with one vented to the outside (ducted).

• NEVER use a gas oven or range to heat your home even for a short time! According to the Centers for Disease Control and Prevention (CDC), between 1988 and 1994, almost 7.7 million people used their gas stove or oven for heat at least once during the previous year. This dangerous practice was most common among rural, low-income, and African-American households.³

• Supply adequate outdoor make-up air for combustion if you use a gas range so there will not be backdrafting into the indoor environment.

• Have a trained professional inspect your gas range every year.

1. Watson T. "Pollution can sneak indoors, scientist warn..." USA Today. September 2, 1999.

2. Garrett MH, Hooper MA, Hooper BM, Abramson MJ. Respiratory symptoms in children and indoor exposure to nitrogen dioxide and gas stoves. American Journal Respiratory and Critical Care Medicine. 1998;158:891-895.

3. Use of Unvented Residential Heating Appliances?United States, 1988-1994, MMWR, December 26, 1997; 46(51):1221-1224.