Wood-burning stoves and fireplaces used to help heat homes may also be producing something less appealing - air pollution.

The American Lung Association of Utah is warning Utahns that smoke from these heaters contains carbon monoxide, hydrocarbon and other organic compounds that can cause respiratory illness. They can also aggravate existing conditions such as bronchitis, emphysema and asthma.Improper burning of wood also causes outdoor pollution. In fact, the Environmental Protection Agency reports that wood stoves and fireplaces emit more carbon monoxide than all U.S. industry combined.

These are some guidelines that consumers with old wood stoves and fireplace inserts can follow to ensure cleaner a more complete burning of fuel and a healthier environment:

- Use only wood that has been split and dried for six months.

- Avoid smoldering, low temperature fires - the greatest polluters.

- Never overload the firebox. This ensures that air circulates freely.

- Never burn garbage, trash or treated wood since they can emit poisonous fumes.

- Above all, watch for signals such as visible smoke from the chimney or lazy flames in the firebox. These are signs that more air is needed for burning.

For additional information on wood stove and fireplace health risks and precautions, contact the Lung Association of Utah at 484-4456.