The burn ban takes effect at 5 p.m. Saturday.
"After a few lingering showers today, weather conditions are expected to become cold and dry. Air pollution is expected to build up to levels unhealthy for sensitive groups, especially in communities where wood-burning is common," the agency said in a prepared statement.
The cold and stagnant conditions are expected to persist into next week, when a weak system is forecast to arrive and disperse pollution.
The purpose of the burn ban is to reduce the amount of pollution from excessive wood smoke. The Clean Air Agency will continue to closely monitor the situation.
During the burn ban:
No burning is allowed in fireplaces or uncertified wood stoves. Residents should rely instead on their home's other, cleaner source of heat (such as their furnace or electric baseboard heaters) for a few days until air quality improves, the public health risk diminishes and the ban is canceled. The only exception is if a wood stove is a home's only adequate source of heat.
No outdoor fires are allowed. This includes recreational fires such as bonfires, campfires and the use of fire pits and chimineas.
Burn ban violations are subject to a $1,000 penalty.
The Clean Air Agency says burn ban enforcement has significantly increased, especially in Tacoma and Pierce County. Increased enforcement and night patrols will increase the likelihood of violators receiving substantial fines this season.
It is permissible to use natural gas, propane, pellet and EPA-certified wood stoves or inserts during a Stage 1 burn ban.
The state Department of Health recommends that people who are sensitive to air pollution limit time spent outdoors, especially when exercising. Air pollution can trigger asthma attacks, cause difficulty breathing, and make lung and heart problems worse.
Air pollution is considered to be especially harmful to people with lung and heart problems, people with diabetes, children, and older adults over age 65.