EUGENE — Woodstove owners in the Eugene-Springfield area have been pouring on the fuel during a cold snap, and air-quality regulators say a buildup of pollution means the burning has to be curbed.

A ban on visible chimney smoke could last through Sunday, when warmer weather is expected.

The Eugene Register-Guard reports such bans may become more frequent because federal standards on particulate pollution have been tightened.

The Lane Regional Air Protection Agency imposed a ban in the mountain town Oakridge on Wednesday.

The ban imposed Thursday in Eugene-Springfield applies to the urban growth boundary. That includes numerous less-developed areas just outside city limits.

It doesn't apply to stoves that burn pellets, and homeowners with efficient stoves burning well-dried wood may be able to get by without creating visible smoke.