For the first time under an effort to reduce smog, Angelenos are being asked to let the home fires go out -- at least until midnight.
Because of a dense fog pattern and an inversion layer that traps pollution in Los Angeles Basin, the regional air-quality agency declared a one- day ban on wood fires in home fireplaces or in outdoor ``chimineas'' to reduce particulate pollution for the downtown area, West Hollywood and much of the San Fernando Valley.
The ban includes artificial logs.
"This is the first time AQMD has issued this type of order under this program," said Sam Atwood of the South Coast Air Quality Management District. "It's our first mandatory no-burn order for the affected area."
The ban shouldn't be too much of a hardship.
Overnight lows are forecast to be mostly in the 50s, with some valley areas dipping into the upper 40s for a few hours. Daytime highs will range from the mid 60s to the mid 70s. Smog is a term coined in England in the 1890s, meaning a combination of fog and smoke, its two essential components.
In Los Angeles, smog is often used to refer to photochemical smog -- the haze produced by the chemical reaction between sunlight, nitrogen oxides and volatile organic compounds. First-time violators could be fined $50, and with fines going up to $500 for repeat offenders.
Such "no burn alerts" are common in Northern and Central California, but rare in the Southland. The ban includes the central San Fernando Valley -- generally north of the Ventura (101 and 134) freeways, east of the San Diego (405) Freeway, south of the Foothill (210) Freeway and west of the Glendale (2) Freeway.
In the L.A. basin, wood fires are banned generally east of Fairfax Avenue, north of Slauson Avenue, and west of the Long Beach (710) Freeway. To find out if home fires are banned, enter your Zip code at www.aqmd.gov/noburn. An inversion layer occurs when cool fog is capped by warmer, drier air. The effect traps pollution close to the surface.