Mailing Address:
South Coast AQMD / Attn: AQ-SPEC
21865 Copley Drive
Diamond Bar, CA 91765-4178
USA

Note: Normal business hours are Tues. - Fri. 7:00 - 5:30 p.m.
Our offices are closed on Mondays and holidays.

For air quality sensor related questions only, please contact AQ-SPEC at:

AQ-SPEC Hotline: +1 (909) 396-2713
e-mail: info.aq-spec@aqmd.gov