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Audit Levels

April 25, 2025

AQS Reference Table

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Assessment Type Parameter Code Parameter Level Lower Limit Upper Limit Units
Annual PE 42101 Carbon monoxide 1 0.02 0.05999 Parts per million
Annual PE 42101 Carbon monoxide 2 0.06 0.19999 Parts per million
Annual PE 42101 Carbon monoxide 3 0.2 0.89999 Parts per million
Annual PE 42101 Carbon monoxide 4 0.9 2.99999 Parts per million
Annual PE 42101 Carbon monoxide 5 3.0 7.99999 Parts per million
Annual PE 42101 Carbon monoxide 6 8.0 15.99999 Parts per million
Annual PE 42101 Carbon monoxide 7 16.0 30.99999 Parts per million
Annual PE 42101 Carbon monoxide 8 31.0 39.99999 Parts per million
Annual PE 42101 Carbon monoxide 9 40.0 49.99999 Parts per million
Annual PE 42101 Carbon monoxide 10 50.0 60.0 Parts per million
NPAP 42101 Carbon monoxide 1 0.02 0.05999 Parts per million
NPAP 42101 Carbon monoxide 2 0.06 0.19999 Parts per million
NPAP 42101 Carbon monoxide 3 0.2 0.89999 Parts per million
NPAP 42101 Carbon monoxide 4 0.9 2.99999 Parts per million
NPAP 42101 Carbon monoxide 5 3.0 7.99999 Parts per million
NPAP 42101 Carbon monoxide 6 8.0 15.99999 Parts per million
NPAP 42101 Carbon monoxide 7 16.0 30.99999 Parts per million
NPAP 42101 Carbon monoxide 8 31.0 39.99999 Parts per million
NPAP 42101 Carbon monoxide 9 40.0 49.99999 Parts per million
NPAP 42101 Carbon monoxide 10 50.0 60.0 Parts per million
Pb Analysis Audit 14129 Lead (TSP) LC 1 4.0 40.0 Micrograms
Pb Analysis Audit 14129 Lead (TSP) LC 2 41.0 125.0 Micrograms
Pb Analysis Audit 85129 Lead PM10 LC FRM/FEM 1 1.0 4.0 Micrograms
Pb Analysis Audit 85129 Lead PM10 LC FRM/FEM 2 5.0 11.0 Micrograms
Annual PE 42602 Nitrogen dioxide (NO2) 1 0.3 2.99 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 2 3.0 4.99 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 3 5.0 7.99 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 4 8.0 19.99 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 5 20.0 49.99999 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 6 50.0 99.99999 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 7 100.0 299.99999 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 8 300.0 499.99999 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 9 500.0 799.99999 Parts per billion
Annual PE 42602 Nitrogen dioxide (NO2) 10 800.0 1000.0 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 1 0.3 2.99 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 2 3.0 4.99 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 3 5.0 7.99 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 4 8.0 19.99 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 5 20.0 49.99999 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 6 50.0 99.99999 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 7 100.0 299.99999 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 8 300.0 499.99999 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 9 500.0 799.99999 Parts per billion
NPAP 42602 Nitrogen dioxide (NO2) 10 800.0 1000.0 Parts per billion
Annual PE 44201 Ozone 1 0.004 0.00599 Parts per million
Annual PE 44201 Ozone 2 0.006 0.01999 Parts per million
Annual PE 44201 Ozone 3 0.02 0.03999 Parts per million
Annual PE 44201 Ozone 4 0.04 0.06999 Parts per million
Annual PE 44201 Ozone 5 0.07 0.08999 Parts per million
Annual PE 44201 Ozone 6 0.09 0.11999 Parts per million
Annual PE 44201 Ozone 7 0.12 0.13999 Parts per million
Annual PE 44201 Ozone 8 0.14 0.16999 Parts per million
Annual PE 44201 Ozone 9 0.17 0.18999 Parts per million
Annual PE 44201 Ozone 10 0.19 0.5 Parts per million
NPAP 44201 Ozone 1 0.004 0.00599 Parts per million
NPAP 44201 Ozone 2 0.006 0.01999 Parts per million
NPAP 44201 Ozone 3 0.02 0.03999 Parts per million
NPAP 44201 Ozone 4 0.04 0.06999 Parts per million
NPAP 44201 Ozone 5 0.07 0.08999 Parts per million
NPAP 44201 Ozone 6 0.09 0.11999 Parts per million
NPAP 44201 Ozone 7 0.12 0.13999 Parts per million
NPAP 44201 Ozone 8 0.14 0.16999 Parts per million
NPAP 44201 Ozone 9 0.17 0.18999 Parts per million
NPAP 44201 Ozone 10 0.19 0.5 Parts per million
Annual PE 42401 Sulfur dioxide 1 0.3 2.99 Parts per billion
Annual PE 42401 Sulfur dioxide 2 3.0 4.99 Parts per billion
Annual PE 42401 Sulfur dioxide 3 5.0 7.99 Parts per billion
Annual PE 42401 Sulfur dioxide 4 8.0 19.99 Parts per billion
Annual PE 42401 Sulfur dioxide 5 20.0 49.99999 Parts per billion
Annual PE 42401 Sulfur dioxide 6 50.0 99.99999 Parts per billion
Annual PE 42401 Sulfur dioxide 7 100.0 149.99999 Parts per billion
Annual PE 42401 Sulfur dioxide 8 150.0 259.99999 Parts per billion
Annual PE 42401 Sulfur dioxide 9 260.0 799.99999 Parts per billion
Annual PE 42401 Sulfur dioxide 10 800.0 1000.0 Parts per billion
NPAP 42401 Sulfur dioxide 1 0.3 2.99 Parts per billion
NPAP 42401 Sulfur dioxide 2 3.0 4.99 Parts per billion
NPAP 42401 Sulfur dioxide 3 5.0 7.99 Parts per billion
NPAP 42401 Sulfur dioxide 4 8.0 19.99 Parts per billion
NPAP 42401 Sulfur dioxide 5 20.0 49.99999 Parts per billion
NPAP 42401 Sulfur dioxide 6 50.0 99.99999 Parts per billion
NPAP 42401 Sulfur dioxide 7 100.0 149.99999 Parts per billion
NPAP 42401 Sulfur dioxide 8 150.0 259.99999 Parts per billion
NPAP 42401 Sulfur dioxide 9 260.0 799.99999 Parts per billion
NPAP 42401 Sulfur dioxide 10 800.0 1000.0 Parts per billion