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Pollutant Standards
April 03, 2025
AQS Reference Table
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Parameter Code | Parameter | Pollutant Standard ID | Pollutant Standard Short Name | Pollutant Standard Description | NAAQS Basis | NAAQS Statistic | Primary Standard Level | Standard Units | Comparison Scale | Round or Truncate | Excludable |
---|---|---|---|---|---|---|---|---|---|---|---|
42101 | Carbon monoxide | 3 | CO 1-hour 1971 | Carbon Monoxide 1-hour standard from 1971. | Obseved hourly values | Annual Second Maximum | 35.0 | Parts per million | 0 | R | |
42101 | Carbon monoxide | 4 | CO 8-hour 1971 | Carbon Monoxide 8-hour running average from 1971. | 8-Hour running average (end hour) of observed hourly values | Annual Second Non-Overlapping Maximum | 9.0 | Parts per million | 0 | R | |
14129 | Lead (TSP) LC | 2 | Lead 3-Month 2009 | Lead 3 month rolling average site level summary based on TSP lead at local conditions. | Observed Values | 3-Month Rolling Average | 0.15 | Micrograms/cubic meter (LC) | 2 | R | |
12128 | Lead (TSP) STP | 1 | Lead Quarterly 1978 | Original lead standard based on calendar quarterly average. | Observed Values | Quarterly Mean | 1.5 | Micrograms/cubic meter (25 C) | 1 | R | |
85129 | Lead PM10 LC FRM/FEM | 14 | Lead 3-Month PM10 Surrogate 2009 | PM10 Surgate (instead of TSP) for the new lead 3 month rolling average site level summary. | Observed Values | 3-Month Roling Average | 0.15 | Micrograms/cubic meter (LC) | 2 | R | |
42602 | Nitrogen dioxide (NO2) | 20 | NO2 1-hour 2010 | Nitrogen Dioxide 1-hour standard | Daily Maximum 1-hour average | Annual 98th Percentile | 100.0 | Parts per billion | 0 | R | |
42602 | Nitrogen dioxide (NO2) | 8 | NO2 Annual 1971 | Nitrogen Dioxide Annual Mean from 1971. | Observed values | Annual Mean | 53.0 | Parts per billion | 0 | R | |
44201 | Ozone | 9 | Ozone 1-hour 1979 | Ozone 1-hour Daily Maximum value based on data completeness betweeen 9 AM and 9 pm. | Daily maxima of observed hourly values (between 9:00 AM and 8:00 PM) | Annual Estimated Days > Standard | 0.12 | Parts per million | 2 | R | |
44201 | Ozone | 10 | Ozone 8-Hour 1997 | Ozone 8-hour running average stored in begin hour from 1997. | Daily maximum of 8 hour running average of observed hourly values | Annual 4th Maximum | 0.08 | Parts per million | 2 | R | |
44201 | Ozone | 11 | Ozone 8-Hour 2008 | Ozone 8-hour running average stored in begin hour from 2008. | Daily maximum of 8 hour running average of observed hourly values | Annual 4th Maximum | 0.075 | Parts per million | 3 | T | |
44201 | Ozone | 23 | Ozone 8-hour 2015 | Ozone 8-hour 2015 -- Daily 8-hour maximum between 7:00 AM and 11:00 PM | Daily maximum of 8-hour running average | Annual 4th Maximum | 0.07 | Parts per million | 3 | T | |
81102 | PM10 Total 0-10um STP | 12 | PM10 24-hour 2006 | PM10 24-hour standard. Violations include actual exceedences and expected exceedences where data is missing. | Daily Mean | Annual Estimated Days > Standard | 150.0 | Micrograms/cubic meter (25 C) | -1 | R | |
88101 | PM2.5 - Local Conditions | 25 | PM25 Annual 1997 | PM25 Annual standard for 1997. Created for Region 9 / AQAD | Quarterly Means of Daily Means | Annual Weighted Mean | 15.0 | Micrograms/cubic meter (LC) | 1 | R | Y |
88101 | PM2.5 - Local Conditions | 24 | PM25 24-hour 1997 | PM25 24-hour standard for 1997. Created for Region 9 / AQAD | Daily Mean | Annual 98th Percentile | 65.0 | Micrograms/cubic meter (LC) | 0 | R | |
88101 | PM2.5 - Local Conditions | 16 | PM25 24-hour 2006 | PM25 24-hour standard made more restrictive in 2006. | Daily Mean | Annual 98th Percentile | 35.0 | Micrograms/cubic meter (LC) | 0 | R | |
88101 | PM2.5 - Local Conditions | 18 | PM25 Annual 2006 | PM25 annual weighted mean was reaffirmed in 2006 with the same level as originally promulgated. | Quarterly Means of Daily Means | Annual Weighted Mean | 15.0 | Micrograms/cubic meter (LC) | 1 | R | Y |
88101 | PM2.5 - Local Conditions | 21 | PM25 24-hour 2012 | PM25 24-hour standard was reaffirmed in 2013 with the same level as previously promulgated. | Daily Mean | Annual 98th Percentile | 35.0 | Micrograms/cubic meter (LC) | 0 | R | |
88101 | PM2.5 - Local Conditions | 22 | PM25 Annual 2012 | PM25 annual standard was lowered in 2013 to increase protection against health effects with long-term exposures. | Quarterly Means of Daily Means | Annual Weighted Mean | 12.0 | Micrograms/cubic meter (LC) | 1 | R | Y |
88101 | PM2.5 - Local Conditions | 27 | PM25 Annual 2024 | PM25 annual standard was lowered in 2024 to increase protection against health effects with long-term exposures. | Quarterly Means of Daily Means | Annual Weighted Mean | 9.0 | Micrograms/cubic meter (LC) | 1 | R | Y |
88101 | PM2.5 - Local Conditions | 26 | PM25 24-hour 2024 | PM25 24-hour standard was reaffirmed in 2024 with the same level as previously promulgated. | Daily Mean | Annual 98th Percentile | 35.0 | Micrograms/cubic meter (LC) | 0 | R | |
42401 | Sulfur dioxide | 7 | SO2 Annual 1971 | Sulfur Dioxide Annual Mean Standard from 1971. | Observed Values | Annual Mean | 30.0 | Parts per billion | 0 | R | |
42401 | Sulfur dioxide | 6 | SO2 24-hour 1971 | Sulfur Dioxide 24-hour standard from 1971. | Daily Average of observed values | Annual Second Maximum | 140.0 | Parts per billion | 0 | R | |
42401 | Sulfur dioxide | 5 | SO2 3-hour 1971 | Sulfur Dioxide 3-hour Block Average from 1971. | 3-Hour block average of observed hourly values | Annual Second Maximum | Parts per billion | 0 | R | ||
42401 | Sulfur dioxide | 19 | SO2 1-hour 2010 | Sulphur Dioxide 1-hour standard from 2010 | Daily maximum 1-hour average | Annual 99th Percentile | 75.0 | Parts per billion | 0 | R | |
42401 | Sulfur dioxide | 28 | SO2 Annual 2024 | Secondary SO2 standard revised to be an annual standard. | Observed Values | Annual Mean | Parts per billion | 0 | R |