AIR EMISSIONS REGULATIONS:

Air Quality Status	In attainment (The APCD is the northern portion of Sonoma County) EPA's Nonattainment Areas
Major Source Threshold	250 tons triggers PSD
Minor Source Permitting Exemption	50 hp or less
Minor Source Treatment	PM and Opacity
Emergency Generating Limits	100 hours for maintenance and testing

DE MINIMIS EXEMPTIONS (Must meet 1298)

Engines up to 50 hp are exempt from permitting. Control officers will exempt additional units on a case-by-case basis.

MINOR SOURCE PERMITTING

The air district does not require BACT unless the source is a toxic hazard. However, there is a 40% opacity limit and PM emissions must be below 0.2 grains per cubic foot.

Emergency engines must be permitted and are required to meet a PM limit of 0.1 g/hphr. Permits will include an hourly limit of up to 100 hours for maintenance and testing. Otherwise units may only operate during emergencies.

TREATMENT OF EMERGENCY ENGINES

There is no special treatment in place. CARB Air Toxic Control Measures for Stationary Compression Engines apply (see the CA state page for more information).