FRESNO, Calif. – For some individuals, the scent of smoke from a barbecue represents good eats. But for the San Joaquin Valley Air Pollution Control District, grill smoke is cause for concern, and the agency is considering ways to regulate smoke from restaurants that use wood fires to cook food.

The district comprises eight counties in California’s Central Valley, and it is governed by a 15-member board. The air district is tasked with reducing overall pollution emissions as required by the federal Clean Air Act and the state California Clean Air Act. The agency already regulates chain restaurants such as Burger King, which use charbroilers and technology that filters dangerous particles.

Now, the agency is seeking restaurants as volunteers to test equipment that will filter out dangerous particles, namely PM-2.5, or fine particulate matter, The Fresno Bee reported. Elevated levels of PM-2.5 in the air can reduce visibility and air quality. Fine particulate matter is a health concern when levels are high.

The San Joaquin Valley faces unique challenges when it comes to meeting federal standards for PM-2.5. The same environmental conditions that make the valley one of the most productive agricultural regions in the country also make it difficult to improve air quality, according to the agency.

The Sierra Nevada provides water needed for growing an abundance of crops, and a temperate climate provides a long growing season. But the mountains trap air pollution and block air flow, while the temperate climate stifles pollutant-dispersing winds. Concentrations of PM-2.5 are highest in the valley during periods of stagnant weather.

Emissions from restaurants that use wood smoke for cooking make up a small fraction of the pollutants in the valley. Cars and trucks generate the most air pollution in the valley, according to the control district, which will decide by 2017 whether to pursue further regulation.