U.S. EPA Approvals
OPSIS Air Quality Monitoring DOAS system is designated equivalent to 40 CFR.
OPSIS UV DOAS AQM system for benzene, ammonia and nitric oxide is U.S. ETV EPA tested.
OPSIS SM200 particulate monitor is designated equivalent method.
U.S. EPA List of Designated Methods >>
Notification for PM2.5 in the Federal Register >>
U.S. EPA website >>
U.S. ETV EPA website >>