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Anchorage DEC offices are experiencing a phone and internet outage. Please call the mainline of the Juneau or Fairbanks office location for assistance. Report oil and hazmat spills in the Anchorage area during business hours or statewide after-hours: 907-891-0757. During business hours, spills in Northern or Southeast regions can still be reported to the respective local response team office.

Design Values FNSB

FNSB PM2.5 Design Value Comparison


The EPA established a health based standard (National Ambient Air Quality Standard, (NAAQS)) for fine particulate matter (PM2.5), which is a byproduct of combustion. The 24 hour PM2.5 standard is based on the 98th percentile averaged over 3 years. The graph below shows the 98th percentiles and design values as measured since 2000 for Fairbanks and North Pole.  An area is in violation of the NAAQS when the Design Value is greater than the 24 hour NAAQS for PM2.5, which is currently set at 35 µg/m3. EPA used data from the State Office Building Monitor in Fairbanks to classify the area as nonattainment. The design value for the Nonattainment Area for 2016-2018 is 65 µg/m3 based on data from the North Pole Fire Hurst Road Monitor (formerly North Pole Fire Station #3).


Note: The vertical axis of this chart extends to 200 µg/m3.

Tabular Data 2012-2018

Year 2012 2013 2014 2015 2016 2017 2018
State Office Building 98th Percentile 49.6 36.3 34.5 35.3 39.7 38 27
State Office Building Design Value 46 41 40 35 37 38 35
NCore 98th Percentile 50.0 36.2 31.6 36.7 30.3 34.4 25.3
NCore Design Value 45 40 39 35 33 34 30
North Pole 98th Percentile 158.4 121.6 138.5 111.6 66.8 75.5 52.8
North Pole Design Value     139 124 106 85 65

NAAQS National Ambient Air Quality Standard - A health-based air quality standard set by EPA based on a review of available scientific information. NAAQS exist for criteria pollutants including Particulate Matter (PM2.5 and PM10), Carbon Monoxide (CO), Sulfur Dioxode (SO2), Nitrogen Dioxide (NO2), Ozone(O3), and Lead(Pb).
EPA's NAAQS Webpage
Concentration, µg/m3 The amount of PM2.5 suspended in the air with units of micrograms(one-millionth of a gram) per cubic meter
Exceedance A day when the 24 hour measured concentration of PM2.5 exceeds the NAAQS.
98th Percentile The daily value out of a year of PM2.5 monitoring data below which 98 percent of all daily values fall.
40 CFR 50 Appendix N - see section 4.5(a) (PDF)
24 hour Design Value (DV) Three year average of the 98th percentile value. An area is in violation of the NAAQS when the Design Values is greater than the 24 hour NAAQS for PM2.5, which is currently set at 35 µg/m3
40 CFR 50 Appendix N - see section 4.5(b) (PDF)
Clean Data Year A year when the 98th percentile value is less than the NAAQS.
Exceptional Events Unusual or naturally occurring events that can affect air quality but are not reasonably controllable.
EPA's Exceptional Events Webpage
DEC's Exceptional Events Webpage
Compliance with PM2.5 NAAQS 24-Hour:  98th percentile, averaged over 3 years, must be below the standard
Annual:   Annual arithmetic mean, averaged over 3 years, must be below the standard.
40 CFR 50 Appendix N - see sections 4.1 and 4.2 (PDF)
PM2.5 NAAQS Values Standard 1997 - 2006 2006 - 2012 2012 - current
24-hour 65 µg/m3 35 µg/m3
Annual 15 µg/m3 12 µg/m3

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