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Download Detailed AQS Data
**ALL THE FILES HAVE BEEN REPLACED DUE TO THE CONVERSION OF THE OLD EXCEPTIONAL EVENT FLAGS**
The table below provides links to files of detail data extracted from the AQS database in input transaction format. These files contain data for the entire country on a year-by-year basis, so many of them are very large files.
All data files are zipped to conserve disk space. Refer to our " Tools" page if you need assistance with file types.
Unless otherwise indicated, the unzipped text files match the Raw Data description in the input transaction format (PDF) (11 pp, 114K, About PDF), i.e., Transaction Type = RD. Hourly data is reported with Duration code = 1; Daily data is reported with Duration = 7. The files follow the naming convention of "RD_501_ppppp_yyyy.ZIP" or "RB_503_ppppp_yyyy.ZIP", where "ppppp" = AQS parameter code (or other name when multiple parameter codes are included) and "yyyy" = year of data.
A text file containing site
and monitor records (ZIP, 32.9M) as of 02/17/11. This
file unzips to a large text file (295M) using different record
types from the same
input transaction format (PDF) (11 pp, 114K,
About PDF).
Site records begin with the letter "A"; monitor records begin with "M".
There is also a file with
descriptions of sites (ZIP, 13M) as of 05/23/12. This file unzips to a PDF in a report format with
one page per site (7375 pp, 17M).
Data Reliability
It is important to understand that some air quality data are more reliable than others.
Various methods are used to collect the data. Some methods are reference methods, some are equivalent methods, and some are neither. As a general matter, data collected using EPA reference methods and/ or equivalent methods provide the highest quality data. Data using other methods maybe less reliable or be more uncertain. More information about reference, equivalent methods and other monitoring methods can be found at EPA's Ambient Monitoring Technology Information Center web site at www.epa.gov/ttn/amtic/ or the broader area of the Air Quality and Assessment Division at http://www.epa.gov/air/oaqps/organization/aqad/io.html .
AQS uses a unique code for each different monitoring method. You can access the table containing all monitoring method codes that describes the monitoring method. If the pollutant being measured is one of the criteria pollutants this sampling methodology code will indicate if it is a reference or equivalent method. The table is at www.epa.gov/ttn/airs/airsaqs/manuals/codedescs.htm.
| Pollutant (Parameter Code) File name (substitute year for "yyyy") |
2012 | 2011 | 2010 | 2009 | 2008 |
2007 |
2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Carbon Monoxide (42101) RD_501_42101_yyyy.ZIP |
42101_2012 1045 KB (18445KB) 05/12/12 |
42101_2011 11267 KB (19627KB) 05/12/12 |
42101_2010 10763 KB (199577KB) 05/12/12 |
42101_2009 10431 KB (206445KB) 05/12/12 |
42101_2008 10566KB (218168KB) 05/12/12 |
42101_2007 10649KB (224159KB) 05/12/12 |
42101_2006 11021KB (232867KB) 05/12/12 |
42101_2005 11771KB (248359KB) 05/12/12 |
42101_2004 12176KB (256346KB) 05/12/12 |
42101_2003 12603KB (262955KB) 05/12/12 |
42101_2002 13248KB (247597KB) 05/12/12 |
42101_2001 14703KB (296633KB) 05/12/12 |
42101_2000 14576KB (298284KB) 05/12/12 |
42101_1999 16114KB (29428KB) 05/12/12 |
42101_1998 15125KB (303718KB) 05/12/12 |
42101_1997 16700KB (305235KB) 05/12/12 |
42101_1996 15371KB (307367KB) 05/12/12 |
42101_1995 16889KB (305667KB) 08/8/11 |
42101_1994 16571KB (297878KB) 4/30/10 |
42101_1993 16221KB (300149KB) 4/30/10 |
| Lead - PB - daily (12128) RD_501_12128_yyyy.ZIP |
12128_2012 1k (3KB) 05/14/12 |
12128_2011 14k (180KB) 05/14/12 |
12128_2010 221k (293KB) 05/14/12 |
12128_2009 35KB (521KB) 05/14/12 |
12128_2008 64KB (949KB) 05/14/12 |
12128_2007 66 KB (975KB) 05/14/12 |
12128_2006 75KB (1138KB) 05/14/12 |
12128_2005 73KB (1136KB) 05/14/12 |
12128_2004 70KB (1105KB) 05/14/12 |
12128_2003 65KB (1032KB) 05/14/12 |
12128_2002 67KB (1065KB) 05/14/12 |
12128_2001 65KB (1008KB) 05/14/12 |
12128_2000 60KB (999KB) 05/14/12 |
12128_1999 65KB (1070KB) 05/14/12 |
12128_1998 76KB (1261KB) 05/14/12 |
12128_1997 92KB (1546KB) 05/14/12 |
12128_1996 105KB (1752KB) 05/14/12 |
12128_1995 109KB (1809KB) 05/14/12 |
12128_1994 118KB (1939KB) 05/14/12 |
12128_1993 134KB (2004KB) 03/18/10 |
| Lead from TSP-(PB TSP) daily (14129) RD_501_14129_yyyy.ZIP |
14129_2012 6KB (90KB) 05/14/12 |
14129_2011 77KB (1115KB) 05/14/12 |
14129_2010 71KB (1039KB) 05/14/12 |
14129 2009 43 KB (650KB) 05/14/12 |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
| Nitrogen Dioxide (42602) RD_501_42602_yyyy.ZIP |
42602_2012 1431 KB (24240KB) 05/16/12 |
42602_2011 13122 KB (231692KB) 05/16/12 |
42602_2010 13424 KB (240929KB) 05/16/12 |
42602_2009 12670KB (237792KB) 05/16/12 |
42602_2008 12507KB (242042KB) 05/16/12 |
42602_2007 12539KB (245258KB) 05/16/12 |
42602_2006 12782KB (248502KB) 05/16/12 |
42602_2005 12881KB (249648KB) 05/16/12 |
42602_2004 13063KB (253753KB) 05/16/12 |
42602_2003 12980KB (250133KB) 05/16/12 |
42602_2002 13175KB (253309KB) 05/16/12 |
42602_2001 13155KB (252212KB) 05/16/12 |
42602_2000 13076KB (250374KB) 05/16/12 |
42602_1999 12811KB (243985KB) 05/16/12 |
42602_1998 12603KB (240956KB) 05/16/12 |
42602_1997 13357KB (234150KB) 05/03/10 |
42602_1996 11822KB (224943KB) 05/16/12 |
42602_1995 11786KB (223379KB) 05/16/12 |
42602_1994 12350KB (214924KB) 03/19/10 |
42602_1993 11410KB (207834KB) 03/19/10 |
| Ozone (44201) - hourly RD_501_44201_yyyy.ZIP |
44201_2012 3481 KB (59658KB) 05/16/12 |
44201_2011 38737KB (654805KB) 05/16/12 |
44201_2010 11311 KB (193234KB) 05/16/12 |
44201_2009 34823KB (606589KB) 05/16/12 |
44201_2008 33408KB (596563KB) 05/16/12 |
44201_2007 32857KB (593365KB) 05/16/12 |
44201_2006 32017KB (577963KB) 05/16/12 |
44201_2005 31673KB (571826KB) 05/16/12 |
44201_2004 34293KB (576694KB) 03/17/11 |
44201_2003 31813KB (573405KB) 05/15/12 |
44201_2002 31380KB (564171KB) 05/15/12 |
44201_2001 30788KB (553675KB) 05/15/12 |
44201_2000 29797KB (536082KB) 05/15/12 |
44201_1999 28755KB (516593KB) 05/15/12 |
44201_1998 28134KB (506173KB) 05/15/12 |
44201_1997 29536KB (492660KB) 09/16/10 |
44201_1996 28350KB (475202KB) 05/03/10 |
44201_1995 28307KB (473813KB) 05/03/10 |
44201_1994 27604KB (463624KB) 05/03/10 |
44201_1993 26315KB (457394KB) 03/22/10 |
| Oxides of Nitrogen - NOX (42603) RD_501_42603_yyyy.ZIP |
42603_2012 1221 KB (20325KB) 05/14/12 |
42603_2011 12310 KB (209879KB) 05/14/12 |
42603_2010 12309 KB (215677KB) 05/14/12 |
42603_2009 11578 KB (209020KB) 05/14/12 |
42603_2008 11262KB (210332KB) 05/14/12 |
42603_2007 11079KB (208599KB) 05/14/12 |
42603_2006 9794KB (182248KB) 05/14/12 |
42603_2005 9661KB (178325KB) 05/14/12 |
42603_2004 9644KB (178711KB) 05/14/12 |
42603_2003 10413KB (175607KB) 05/05/10 |
42603_2002 10409KB (174900KB) 05/05/10 |
42603_2001 9979KB (166840KB) 05/05/10 |
42603_2000 9901KB (164951KB) 05/05/10 |
42603_1999 9866KB (163132KB) 09/16/10 |
42603_1998 9416KB (156798KB) 09/16/10 |
42603_1997 9129KB (151451KB) 09/16/10 |
42603_1996 8989KB (14357KB) 09/16/10 |
42603_1995 8813KB (145045KB) 09/16/10 |
42603_1994 8162KB (133755KB) 05/05/10 |
42603_1993 5426KB (90515KB) 3/25/10 |
| PAMS VOC1 RD_501_PAMS VOC_yyyy.ZIP |
PVOC 2012 2994 KB (49350KB) 05/16/12 |
PVOC 2011 38826 KB (670693KB) 05/16/12 |
PVOC 2010 37098 KB (639619KB) 05/16/12 |
PVOC_2009 36215KB (616406KB) 05/16/12 |
PVOC_2008 36213KB (613060KB) 05/16/12 |
PVOC_2007 39874KB (664006KB) 05/16/12 |
PVOC_2006 37882KB (627441KB) 05/16/12 |
PVOC_2005 35216KB (577851KB) 05/16/12 |
PVOC_2004 32004KB (526190KB) 05/16/12 |
PVOC_2003 31405KB (511644KB) 05/15/12 |
PVOC_2002 33726KB (565594KB) 05/15/12 |
PVOC_2001 30967KB (521106KB) 05/15/12 |
PVOC_2000 30031KB (507904KB) 05/15/12 |
PVOC_1999 28841KB (492765KB) 05/15/12 |
PVOC_1998 27994KB (471919KB) 05/15/12 |
PVOC_1997 25102KB (386472KB) 08/18/11 |
PVOC_1996 19572KB (300425KB) 08/18/11 |
PVOC_1995 14472KB (223349KB) 08/18/11 |
PVOC_1994 5715KB (83678KB) 08/18/11 |
PVOC_1993 2193KB (33724KB) 08/18/11 |
| PM 2.5 - Local Conditions4 (88101) RD_501_88101_yyyy.ZIP |
88101_2012 957 KB (16010KB) 05/16/12 |
88101_2011 8768 KB (149980KB) 05/16/12 |
88101_2010 6345 KB (105668KB) 05/16/12 |
88101_2009 3397KB (56876KB) 05/16/12 |
88101_2008 1078KB (16396KB) 05/16/12 |
88101_2007 784KB (11187KB) 05/16/12 |
88101_2006 747KB (10680KB) 05/16/12 |
88101_2005 791KB (11257KB) 05/16/12 |
88101_2004 791KB (11408KB) 05/16/12 |
88101_2003 803KB (11594KB) 05/16/12 |
88101_2002 888KB (12913KB) 05/16/12 |
88101_2001 884KB (12797KB) 05/16/12 |
88101_2000 835KB (12056KB) 05/16/12 |
88101_1999 624KB (8392KB) 10/1/10 |
88101_1998 4KB (48KB) 6/04/09 |
88101_1997 4KB (9KB) 4/2/10 |
no data reported |
no data reported |
no data reported |
no data reported |
| PM Fine Speciation2,3,5 RD_501_SPEC_yyyy.ZIP |
SPEC_2012 739 KB (8275KB) 05/16/12 |
SPEC_2011 5801 KB (70667KB) 05/16/12 |
SPEC_2010 5475 KB (66692KB) 05/16/12 |
SPEC_2009 6240KB (68605KB) 08/19/11 |
SPEC_2008 6915KB (80947KB) 08/19/11 |
SPEC_2007 7085KB (80666KB) 08/19/11 |
SPEC_2006 7750KB (86013KB) 08/19/11 |
SPEC_2005 8999KB (99430KB) 08/19/11 |
SPEC_2004 9178KB (103442KB) 08/19/11 |
SPEC_2003 8762KB (97091KB) 08/19/11 |
SPEC_2002 7568KB (86644KB) 09/17/10 |
SPEC_2001 3555KB (42552KB) 09/17/10 |
SPEC_2000 1197KB (14330KB) 09/17/10 |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
| PM Fine Speciation-Blanks6 RD_503_Blanks_yyyy.ZIP |
BLANKS_2012 34KB (471KB) 05/14/12 |
BLANKS_2011 377KB (5551KB) 05/14/12 |
BLANKS_2010 754KB (11047KB) 05/14/12 |
BLANKS_2009 652KB (9262KB) 05/14/12 |
BLANKS_2008 669KB (9261KB) 05/14/12 |
BLANKS_2007 908KB (12036KB) 05/14/12 |
BLANKS_2006 1100KB (14060KB) 05/14/12 |
BLANKS_2005 1314KB (16784KB) 05/14/12 |
BLANKS_2004 1498KB (20115KB) 05/14/12 |
BLANKS_2003 1333KB (17148KB) 05/17/12 |
BLANKS_2002 952KB (11994KB) 05/17/12 |
BLANKS_2001 478KB (6262KB) 05/17/12 |
BLANKS_2000 117KB (1658KB) 05/17/12 |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
no data reported |
| PM Fine Speciation-IMPROVE7 RD_501_IMPROVE_yyyy.ZIP |
No Data Reporte | No Data Reported |
IMPROVE_2010 4647KB (47378KB) 08/19/11 |
IMPROVE_2009 7106 KB (72400KB) 08/19/11 |
IMPROVE_2008 7226KB (72858KB) 08/19/11 |
IMPROVE_2007 8854KB (85581KB) 08/19/11 |
IMPROVE_2006 8566KB (81956KB) 08/19/11 |
IMPROVE_2005 8765KB (91827KB) 05/16/12 |
IMPROVE_2004 10911KB (104936KB) 08/19/11 |
IMPROVE_2003 9991KB (94935KB) 08/19/111 |
IMPROVE_2002 9090KB (85601KB) 08/19/11 |
IMPROVE_2001 7651KB (71484KB) 08/19/11 |
IMPROVE_2000 4960KB (47694KB) 08/19/11 |
IMPROVE_1999 3668KB (37661KB) 08/19/11 |
IMPROVE_1998 3757KB (38032KB) 08/19/11 |
IMPROVE_1997 3816KB (38172KB) 08/19/11 |
IMPROVE_1996 3642KB (36436KB) 08/19/11 |
IMPROVE_1995 3554KB (35289KB) 08/19/11 |
IMPROVE_1994 3437KB (33450KB) 08/19/11 |
IMPROVE_1993 2914KB (28455KB) 08/19/11 |
| PM 10 (81102) RD_501_81102_yyyy.ZIP |
81102_2012 1026 KB (16905KB) 05/17/12 |
81102_2011 9730 KB (157943KB) 05/17/12 |
81102_2010 9259 KB (147890KB) 05/17/12 |
81102_2009 8636KB (141383KB) 05/17/12 |
81102_2008 8268KB (136328KB) 05/16/12 |
81102_2007 7809KB (129255KB) 05/16/12 |
81102_2006 7753KB (128196KB) 05/16/12 |
81102_2005 7606KB (125694KB) 05/16/12 |
81102_2004 7060KB (116266KB) 08/22/11 |
81102_2003 6510KB (106660KB) 05/16/12 |
81102_2002 6196KB (101597KB) 05/16/12 |
81102_2001 5971KB (97413KB) 05/16/12 |
81102_2000 4791KB (78079KB) 05/16/12 |
81102_1999 4026KB (65522KB) 05/16/12 |
81102_1998 4351KB (72457KB) 05/16/12 |
81102_1997 4819KB (81217KB) 05/16/12 |
81102_1996 4332KB (72798KB) 05/16/12 |
81102_1995 3687KB (61754KB) 05/16/12 |
81102_1994 2892KB (48195KB) 05/16/12 |
81102_1993 1963KB (29861KB) 05/06/10 |
| PM 2.5 Non Reference Method8 -Hourly (88501 & 88502 ) RD_501_88501_2_yyyy.ZIP |
88501/2 2012 19809 KB (296782KB) 05/16/12 |
88501/2 2011 19809 KB (296782KB) 12/29/11 |
88501/2 2010 27081 KB (451081KB) 05/16/12 |
88501/2_2009 28443KB (461979KB) 05/16/12 |
88501/2_2008 28295KB (469399KB) 05/16/12 |
88501/2 2007 26231KB (434031KB) 05/16/12 |
88501/2_2006 21930KB (366452KB) 05/16/12 |
88501/2_2005 18980KB (317315KB) 05/16/12 |
88501/2_2004 15615KB (261400KB) 05/16/12 |
88501/2_2003 11773KB (199497KB) 08/22/11 |
88501/2_2002 8338KB (140559KB) 05/16/12 |
88501/2_2001 5808KB (97366KB) 05/16/12 |
88501/2_2000 3505KB (57825KB) 05/16/12 |
88501/2_1999 986KB (16410KB) 05/16/12 |
88501/2_1998 208KB (3345KB) 5/14/10 |
88501/2_1997 42KB (734KB) 5/14/10 |
no data reported |
no data reported |
no data reported |
no data reported |
| Reactive Oxides of Nitrogen - NOY (42600) RD_501_42600_yyyy.ZIP |
42600_2012 394KB (6280KB) 05/14/12 |
42600_2011 3185KB (50354KB) 05/14/12 |
42600_2010 1503KB (23643KB) 05/14/12 |
42600_2009 43KB (650KB) 05/14/12 |
42600_2008 1335KB (19554KB) 4/7/10 |
42600_2007 928KB (15140KB) 03/15/12 |
42600_2006 878KB (13468KB) 05/06/10 |
42600_2005 745KB (11744KB) 4/7/10 |
42600_2004 644KB (10041KB) 4/7/10 |
42600_2003 567KB (9182KB) 4/7/10 |
42600_2002 524KB (8311KB) 4/7/10 |
42600_2001 633KB (9994KB) 4/7/10 |
42600_2000 517KB (8101KB) 4/7/10 |
42600_1999 544KB (8486KB) 4/7/10 |
42600_1998 561KB (9108KB) 4/7/10 |
42600_1997 325KB (4973KB) 4/7/10 |
42600_1996 280KB (4279KB) 4/7/10 |
42600_1995 224KB (3472KB) 4/7/10 |
no data reported |
no data reported |
| Sulfur Dioxide (42401) RD_501_42401_ 1H_yyyy.ZIP (Hourly data) |
42401 2012 1855KB (37512KB) 05/16/12 |
42401 2011 13240KB (271893KB) 05/16/12 |
42401 2010 12988KB (272258KB) 05/16/12 |
42401_2009 13033KB (278692KB) 05/16/12 |
42401_2008 13735KB (294229KB) 05/16/12 |
42401_2007 14425KB (310506KB) 05/16/12 |
42401_2006 14252KB (309154KB) 05/16/12 |
42401_2005 14673KB (316340KB) 05/16/12 |
42401_2004 16353KB (322704KB) 09/13/10 |
42401_2003 15279KB (327568KB) 05/16/12 |
42401_2002 15279KB (327568KB) 05/16/12 |
42401_2001 16423KB (350675KB) 05/16/12 |
42401_2000 16969KB (359781KB) 05/16/12 |
42401_1999 17425KB (367690KB) 05/16/12 |
42401_1998 18283KB (386480KB) 05/16/12 |
42401_1997 20537KB (396496KB) 05/06/10 |
42401_1996 21075KB (407630KB) 05/06/10 |
42401_1995 21343KB (412689KB) 05/06/10 |
42401_1994 21562KB (410096KB) 4/7/10 |
42401_1993 21680KB (414204KB) 4/7/10 |
| Sulfur Dioxide (42401) RD_501_42401_5M_yyyy.ZIP (5 minute data) |
42401 2012 6813KB (145221KB) 05/17/12 |
42401 2011 23845KB (471261KB) 05/17/12 |
42401 2010 22483KB (506217KB) 05/17/12 |
42401_2009 713KB (15658KB) 05/17/12 |
42401_2008 998KB (22406KB) 05/17/12 |
42401_2007 1329KB (30398KB) 05/17/12 |
42401_2006 1340KB (30490KB) 05/17/12 |
42401_2005 1730KB (39611KB) 05/17/12 |
42401_2004 1790KB (40540KB) 05/17/12 |
42401_2003 1479KB (32639KB) 05/17/12 |
42401_2002 4124KB (91482KB) 05/17/12 |
42401_2001 478KB (9585KB) 05/17/12 |
42401_2000 17419KB (366902KB) 05/17/12 |
42401_1999 17952KB (373818KB) 05/17/12 |
42401_1998 18310KB (386967KB) 05/17/12 |
42401_1997 20537KB (396496KB) 05/06/10 |
42401_1996 21075KB (407630KB) 05/06/10 |
42401_1995 21343KB (412689KB) 05/06/10 |
42401_1994 21562KB (410096KB) 4/7/10 |
42401_1993 21680KB (414204KB) 4/7/10 |
1 parmcodesbyclasscode.xls (9/27/07, 84K) Look in spreadsheet for "Volatile Organic Compound subset of the PAMS Parameters"
2 parmcodesbyclasscode.xls (9/27/07, 84K) Look in spreadsheet for "PM2.5 Speciation"
3 Current speciation data files contain the "raw" speciation data from the national PM2.5 network. The organic carbon data are reported as measured and have not been blank-corrected. The EPA is currently exploring options for correcting carbon data. Guidance will be posted when available. Please review the attached technical note from Phil Lorang.
4 Before 2008, 88101 (PM2.5 at local conditions) data only includes the filter-based methods so only 24-hr duration data; no hourly data is available. The continuous monitors (hourly measurements) for PM2.5 didn't receive FRM approval until mid-2007, and thia dta wasn't accepted as 88101 datain AQS until Jan. 2008.5 "RD_501_SPEC_yyyy.ZIP" - These files contain the PM2.5 data concentrations as well as analysis of the particulate for metals, sulfate, nitrate, carbon, etc. that helps to determine what is the main cause of the particulate concentrations. These data (including the different chemical analysis that are performed) are not collected with EPA approved reference or equivalent methods, but rather methods designed specifically for this type of analyses and as such for PM2.5. There is more uncertainty associated with these data. These data are generally not used for regulatory purposes but more for research and to assist in control strategy development. These samples are collected with 24-hr samplers midnight to midnight local standard time with different sampling frequencies depending on the site location.
6 "RD_503_Blanks_yyyy.ZIP" (PM Fine Speciation-Blanks) - The Blanks data files are for the PM2.5 speciation sites and parameters, and reflect the concentrations of the individual species determined for both “TRIP” and “FIELD”. These data values are reported to AQS beginning in 2003. These files use a different format - "RB" instead of RD. The "503" in the file names also indicates this different format.
7 "RD_501_IMPROVE_yyyy.ZIP" (PM Fine Speciation–IMPROVE) -
The “Interagency Monitoring of Protected Visual Environments” data for 1988 to 2004
(also available from http://vista.cira.colostate.edu/IMPROVE/
)
are available here in AQS format to simplify the combined analysis with the PM2.5
speciation data. Data for earlier years not included in the table above
are available upon request.
8 This file contains non-reference method continuous PM2.5 data, which includes the pre-2008 hourly PM2.5 data that was not accepted as 88101. This file includes 88500/PM2.5 Total Atmospheric, 88501/PM2.5 Raw Data or 88502/Acceptance PM2.5 AQI and speciation mass.
SO2 is displayed Hourly
More information about PM2.5 monitoring methods can be found on EPA's Ambient Monitoring Technology Center web site at www.epa.gov/ttn/amtic. Information about the new PM rule is available at http://epa.gov/pm/actions.html.
New files may be added from time to time, and some files may be updated from time to time. Files for the more current years, will be updated twice a year: May and November. The date of extraction for each file is noted in the table above along with the file name and size.
File names beginning with "RD_501" indicate the file was created using the AMP501 - Extract Raw Data Report. AMP501 produces a zipped file that includes a "pdf" file that is actually the cover page showing the criteria used to create the file, and a "txt" file with the reported sample values.
File names beginning with "RB_503" indicate the file was created using the AMP503 - Extract Blanks Data Report. Like AMP501, AMP503 produces a zipped file that includes a "pdf" file that is the cover page showing the criteria used to create the file, and a "txt" file with the reported sample values.
If you find an error in AQS, we hope you will let us know so that we may correct it. You may use the Contact Us link or you may contact the people directly responsible for the data. Air monitoring: state environmental agencies
For data not otherwise available, please use the AQS Data Mart.