Table 6-21-Hour and 8-Hour Maximum Carbon Monoxide Levels at Monitoring Stations Throughout the United States

1-Hour carbon monoxide level8-Hour carbon monoxide level
Number of
measure-
ments
First
maximum
(ppmv)
Second
maximum
(ppmv)
Number
exceeding
average
First
maximum
(ppmv)
Second
maximum
(ppmv)
Number
exceeding
average
CityStatea
2,169  8.1  6.70  3.63.50FairbanksAK
2,176  6.1  60  4.13.80AnchorageAK
1,988  5.1  4.50  2.52.30Not providedAK
2,176  5.6  5.50  3.12.80AnchorageAK
2,173  5.7  4.50  3.32.20FairbanksAK
2,173  8.3  80  4.84.70AnchorageAK
7,50019.615.9010.78.11BirminghamAL
7,563  8  6.10  2.32.20FairfieldAL
8,012  3.4  30  2.42.30BirminghamAL
8,750  6.8  2.50  1.81.50North Little RockAR
5,049  1.5  1.40  110SurpriseAZ
4,584  0.7  0.70  0.50.50Not providedAZ
7,947  3.1  3.10  2.52.40PhoenixAZ
8,720  2.2  1.80  1.310TucsonAZ
8,736  2.6  2.10  1.11.10TucsonAZ
8,696  2.9  2.50  1.41.30TucsonAZ
4,369  2.5  2.50  1.91.50TucsonAZ
8,157  1.5  1.30  10.90TucsonAZ
4,315  2  1.80  1.31.20TucsonAZ
5,027  2.4  2.30  1.81.40TempeAZ
5,043  1.8  1.70  1.41.40ChandlerAZ
5,057  3.7  3.20  2.220PhoenixAZ
8,654  3  30  2.72.40PhoenixAZ
4,933  2  20  1.51.40ScottsdaleAZ
5,060  2.1  20  1.61.50GlendaleAZ
5,038  2.1  20  1.31.30PhoenixAZ
5,012  1.7  1.70  1.41.30MesaAZ
8,575  4.7  4.50  3.130PhoenixAZ
8,307  3.9  3.60  2.82.80PhoenixAZ
8,397  3.6  3.50  2.62.20PhoenixAZ
6,905  2.1  1.90  1.110LompocCA
6,893  1.4  1.20  0.60.60GoletaCA
6,097  1.6  1.30  0.70.60Vandenberg Air Force BaseCA
6,177  3.3  30  2.11.90San JoseCA
7,046  7.6  3.70  1.31.10DavenportCA
6,230  2.7  2.50  1.91.70VallejoCA
6,251  0.9  0.90  0.70.60BeniciaCA
6,244  3.5  1.90  1.31.10Santa RosaCA
5,550  2.8  2.30  1.81.70ModestoCA
6,035  1.9  1.90  1.21.20TurlockCA
6,270  2.2  2.20  1.41.40LivermoreCA
6,227  2.9  2.40  1.61.40OaklandCA
6,202  1.9  1.80  1.31.30Fremont (Centerville)CA
6,175  2.1  20  1.51.50BerkeleyCA
5,576  3.1  30  2.42.10ChicoCA
6,240  1.5  1.50  110ConcordCA
6,274  1  0.90  0.80.80Bethel IslandCA
6,225  2.5  2.10  1.30.90San PabloCA
6,266  2.8  2.20  1.41.30PittsburgCA
5,430  2.6  2.60  1.81.70FresnoCA
5,563  3.1  2.80  2.32.10FresnoCA
5,519  1.6  1.50  110FresnoCA
4,785  2.3  2.20  1.51.30ClovisCA
5,768  1.9  1.90  1.61.40EurekaCA
5,543  8.2  70  5.34.10CalexicoCA
5,262  7.3  6.80  3.23.10CalexicoCA
6,270  2.5  2.30  1.71.70El CentroCA
4,139  3.5  2.70  2.22.10BakersfieldCA
5,554  2.3  2.10  1.41.30AzusaCA
5,552  2.7  2.30  1.81.70West Los AngelesCA
5,555  3  2.80  2.520BurbankCA
5,560  2.9  2.80  21.90Los AngelesCA
5,594  3.4  3.30  2.32.10ResedaCA
5,579  5.8  5.70  4.34.10LynwoodCA
5,281  2.9  2.50  1.91.80Pico RiveraCA
5,557  2.6  2.60  1.71.70PomonaCA
5,550  2.4  2.40  21.90PasadenaCA
5,567  3.3  30  2.52.40Long BeachCA
5,315  3.1  2.60  1.91.80Los AngelesCA
5,495  1.6  1.50  0.90.80Santa ClaritaCA
5,538  2.2  1.70  0.90.80LancasterCA
6,208  1.7  1.70  110San RafaelCA
7,224  4.5  3.90  3.43.30UkiahCA
3,282  1.5  1.40  10.90WillitsCA
7,177  2.2  1.60  0.90.80SalinasCA
6,255  3.2  3.10  1.81.60NapaCA
5,560  3.3  30  2.42.10AnaheimCA
5,571  3  2.80  220Costa MesaCA
5,524  1.5  1.50  1.110Mission ViejoCA
5,567  4.7  4.60  2.52.40La HabraCA
5,605  4.7  4.50  1.91.90RiversideCA
5,574  1  0.90  0.50.50Palm SpringsCA
5,546  2.7  2.50  1.91.70Rubidoux (West Riverside)CA
5,564  1.1  1.10  0.80.80Lake ElsinoreCA
6,390  2.3  2.30  1.81.80North HighlandsCA
7,292  2.9  2.70  2.51.80SacramentoCA
8,036  3.1  3.10  2.82.40SacramentoCA
4,812  2.7  2.50  1.81.70SacramentoCA
5,519  1.4  1.30  1.21.10BarstowCA
5,587  1.4  1.40  0.90.90VictorvilleCA
5,491  2.1  1.90  1.41.20UplandCA
1,388  1.3  1.10  0.80.80FontanaCA
5,556  2.2  2.10  1.41.40San BernardinoCA
6,212  2  20  1.51.50Chula VistaCA
706  2.4  2.20  1.81.50San DiegoCA
6,006  4.6  40  2.82.50EscondidoCA
6,130  3.1  3.10  2.52.50San DiegoCA
5,119  4.3  3.90  2.72.50Otay MesaCA
6,247  2.1  1.90  1.51.40San FranciscoCA
5,546  2.6  2.50  1.61.60StocktonCA
6,214  4.3  3.80  1.91.80Redwood CityCA
4,811  5.2  3.40  1.21.20Santa BarbaraCA
5,462  1.5  1.50  0.80.80Santa MariaCA
6,182  3.5  2.50  1.70.90CapitanCA
6,190  3.1  3.10  2.41.70WelbyCO
6,505  3.5  3.30  2.72.40LongmontCO
6,507  3.4  3.20  2.32.20GreeleyCO
6,481  2.2  2.10  1.41.30Grand JunctionCO
6,487  5.1  4.60  32.20Fort CollinsCO
4,249  0.8  0.80  0.70.70Not providedCO
6,420  4  3.50  2.62.30Colorado SpringsCO
6,203  7.1  70  3.12.30DenverCO
6,488  4.8  4.50  2.41.90DenverCO
6,499  6  5.90  3.73.10HartfordCT
6,319  1.6  1.60  1.41.10WestportCT
6,305  3.3  3.20  2.220BridgeportCT
6,491  1.2  1.10  0.90.90ThomastonCT
6,511  1.8  1.60  1.31.20East HartfordCT
3,314  2.2  2.10  1.91.60New HavenCT
6,525  6  40  2.61.80WashingtonDC
6,513  3  2.70  2.62.10WashingtonDC
7,030  1.4  10  0.90.80Not providedDE
7,171  2  20  1.31.10WilmingtonDE
6,500  2.1  20  1.61.60Fort LauderdaleFL
6,513  1.6  1.50  10.90ClearwaterFL
6,499  2.4  2.10  1.61.50HollywoodFL
6,269  8.7  6.20  3.32.80JacksonvilleFL
6,318  2.5  2.10  1.41.20JacksonvilleFL
6,250  2.3  2.20  1.11.10JacksonvilleFL
6,551  2.6  2.50  21.80TampaFL
6,511  1.2  10  0.50.40Plant CityFL
6,506  2.2  20  1.21.10MiamiFL
6,515  2.4  20  1.71.40Not providedFL
6,329  3.9  3.90  2.42.10MiamiFL
6,550  2.8  2.60  2.11.60MiamiFL
6,449  1.1  10  110Winter ParkFL
2,167  1.5  1.40  1.11.10Palm BeachFL
6,280  1.5  1.40  1.21.10Pompano BeachFL
5,747  2.8  2.10  1.81.80DecaturGA
6,435  0.5  0.50  0.50.50Not providedGA
5,918  2.2  2.10  1.41.20AtlantaGA
6,554  2.1  1.70  110HonoluluHI
5,268  1.7  1.30  0.70.70Ewa BeachHI
2,050  1.5  1.10  0.70.60Cedar RapidsIA
5,017  1.6  1.50  1.31.20Cedar RapidsIA
7,396  1.9  1.60  110Des MoinesIA
8,199  1.2  1.20  0.70.70DavenportIA
4,609  4.1  3.60  1.61.50BoiseID
7,797  2.9  2.70  2.32.20East Saint LouisIL
7,977  2.5  2.20  1.51.30SpringfieldIL
7,965  5.6  30  1.91.70RockfordIL
7,917  3.6  3.20  2.92.10PeoriaIL
7,960  2.5  2.50  2.32.20MaywoodIL
8,007  1.9  1.30  1.20.90NorthbrookIL
7,926  2.4  2.30  1.71.50CiceroIL
7,783  2.3  20  1.81.50Schiller ParkIL
7,982  7.3  4.40  21.50ChicagoIL
6,380  1.9  1.70  1.21.20Indianapolis (Remainder)IN
5,972  2  1.80  1.51.10EvansvilleIN
6,538  9.1  7.10  3.330East ChicagoIN
3,984  0.8  0.80  0.70.70PittsboroIN
6,445  3.9  3.80  2.92.30Fort WayneIN
8,710  3.6  3.50  3.22.10IndianapolisIN
6,520  2.8  2.70  21.20WichitaKS
6,394  2.7  2.40  1.61.50WichitaKS
6,389  2.2  2.20  1.81.40Kansas CityKS
7,113  6.9  3.40  2.82.20LouisvilleKY
6,937  3.1  3.10  2.72.10LouisvilleKY
7,723  2.9  2.50  1.91.80Baton RougeLA
5,769  0.9  0.70  0.40.40LynnMA
6,586  3.4  3.40  32.50SpringfieldMA
6,835  3.7  3.20  2.62.10LowellMA
6,830  1.7  1.60  1.310BostonMA
6,875  1.5  1.50  1.10.90BostonMA
6,831  2.8  2.70  1.71.30WorcesterMA
6,022  2.6  2.40  1.61.50EssexMD
6,407  0.4  0.40  0.30.30Not providedMD
6,104  2.4  2.20  2.120BaltimoreMD
6,439  1.4  10  0.90.80BeltsvilleMD
1,211  0.6  0.60  0.40.40Presque IsleME
5,816  1.6  1.40  1.310PortlandME
6,351  0.4  0.40  0.40.30Not providedME
4,569  2  1.60  1.21.10Allen ParkMI
4,218  2  1.80  1.110Grand RapidsMI
7,278  2  20  0.80.70MinneapolisMN
7,262  0.5  0.50  0.30.30Inver Grove HeightsMN
5,712  0.6  0.60  0.40.30RosemountMN
2,169  1.8  1.50  1.21.20FridleyMN
7,022  3.2  3.10  2.42.40St. PaulMN
6,975  1.8  1.70  1.21.20St. CloudMN
7,122  4.1  2.20  1.81.50DuluthMN
6,533  1.1  10  0.70.70Sunset HillsMO
6,536  1.9  1.80  1.210SpringfieldMO
6,528  3.3  2.90  2.21.60St. LouisMO
6,469  2.4  2.10  1.81.40St. LouisMO
2,083  3.4  3.40  2.92.70MissoulaMT
2,104  2  1.90  0.70.70Not providedMT
6,916  6.7  5.70  2.42.20West YellowstoneMT
1,542  6.1  4.20  1.61.10Not providedMT
7,130  4.8  3.70  2.320BillingsMT
7,244  7.7  30  1.81.50Great FallsMT
5,578  7.2  3.40  2.41.90KalispellMT
2,819  1.5  1.50  1.31.10Not providedNC
7,811  1.9  1.80  1.51.40CharlotteNC
3,664  3.5  3.10  2.22.20RaleighNC
7,081  4  2.80  2.41.80RaleighNC
7,384  1.6  1.50  0.90.70RockwellNC
2,044  2.2  2.20  1.71.70FayettevilleNC
7,927  2.3  2.10  1.91.60CharlotteNC
1,985  1.9  1.90  1.61.50GreensboroNC
6,531  2.7  2.50  2.31.90Winston-SalemNC
2,754  1.9  1.90  1.51.20DurhamNC
7,930  6.5  1.70  1.20.70Not providedND
6,365  3.1  2.90  2.520OmahaNE
7,252  6.5  4.50  1.81.80LincolnNE
6,464  9.4  60  4.43.50ManchesterNH
6,285  1.5  1.40  1.11.10Fort LeeNJ
2,188  1.8  1.60  1.110ElizabethNJ
6,544  2.3  1.90  1.51.30MorristownNJ
6,508  3.4  3.40  21.60FreeholdNJ
6,373  2.2  2.10  1.21.20CamdenNJ
6,522  1  0.90  0.70.60Not providedNJ
6,498  2.1  2.10  1.71.50Jersey CityNJ
6,318  2  1.60  1.20.90Perth AmboyNJ
6,484  2.2  2.20  1.81.60HackensackNJ
6,326  3.7  2.70  1.81.40BurlingtonNJ
3,065  3.6  2.80  1.81.50AlbuquerqueNM
6,140  2.6  2.20  1.71.10AlbuquerqueNM
3,130  2.6  2.50  1.81.70AlbuquerqueNM
5,792  6.5  30  2.42.30AlbuquerqueNM
3,057  4.9  3.70  1.61.30AlbuquerqueNM
806  2.4  2.40  1.91.80South ValleyNM
6,377  4.2  3.90  2.120SparksNV
6,463  2.2  1.90  1.51.50Lemmon Valley-Golden ValleyNV
4,243  2.9  2.70  2.21.70Carson CityNV
5,033  3.5  2.90  2.32.10Las VegasNV
6,217  5.1  4.70  4.23.70Las VegasNV
6,275  4.1  3.90  3.12.80Las VegasNV
6,190  3.2  2.90  2.12.10Las VegasNV
6,271  4.2  3.60  2.52.40Las VegasNV
6,178  5.8  5.30  2.62.40StatelineNV
6,476  2.1  2.10  1.51.50RenoNV
6,515  1.8  1.70  1.31.30RenoNV
6,400  3  2.90  2.32.20RenoNV
6,512  1.8  1.70  0.80.80RenoNV
6,466  1.8  1.80  1.20.90HoltsvilleNY
7,922  3  2.70  1.81.80SchenectadyNY
7,445  8.6  2.30  1.71.60New YorkNY
7,956  2  1.90  1.71.40SyracuseNY
7,957  1.4  1.30  1.210Niagara FallsNY
7,769  1.5  1.20  10.90AlbanyNY
4,245  1.6  1.50  1.21.20New YorkNY
7,429  1.3  1.20  1.110RochesterNY
5,757  1.3  10  0.70.70TonawandaNY
7,452  1.6  1.60  1.110BuffaloNY
7,962  2.3  2.10  1.81.70New YorkNY
3,419  1.7  1.60  1.31.20New YorkNY
6,967  4.8  4.80  2.11.50ClevelandOH
7,023  7.8  6.30  3.32.40ClevelandOH
6,948  2  1.50  0.90.80AkronOH
7,003  1.7  1.60  1.31.10AkronOH
6,158  2.9  2.90  2.62.50CantonOH
8,739  2.3  2.30  1.61.50DaytonOH
8,720  1.5  1.40  1.110DaytonOH
7,259  2.6  2.60  2.62.30MentorOH
6,358  5.9  5.10  3.62.70CincinnatiOH
7,183  2.7  2.30  1.61.40ColumbusOH
7,232  2  1.80  1.51.30ClevelandOH
7,252  2  20  1.21.20ClevelandOH
7,752  2.5  2.10  1.11.10Oklahoma CityOK
1,382  0.4  0.40  0.30.30Cherry TreeOK
3,185  1.7  0.50  0.40.30Park HillOK
4,625  1.7  0.30  0.50.30Not providedOK
2,278  1.7  1.60  1.41.30TulsaOK
7,991  2.1  1.90  1.31.20TulsaOK
5,933  2.7  2.60  2.32.20PortlandOR
6,541  2.7  2.70  1.81.60PortlandOR
6,437  3.4  3.40  2.62.20MedfordOR
6,530  2.2  2.10  1.71.60EugeneOR
5,023  0.8  0.80  0.50.40Not providedPA
7,048  1.9  1.80  1.61.50PittsburghPA
7,243  2  20  1.31.20YorkPA
7,211  1.4  10  0.80.50GreensburgPA
6,517  1.6  1.60  1.31.10PittsburghPA
6,523  2.3  2.10  1.71.40PittsburghPA
7,054  2.6  20  1.61.30Beaver FallsPA
7,197  1.5  1.30  0.90.90Not providedPA
7,206  1.4  1.20  0.80.70AltoonaPA
7,009  4.3  2.90  21.90BristolPA
7,215  1.7  1.40  1.21.10JohnstownPA
7,174  1.4  1.40  1.11.10HarrisburgPA
7,152  2.8  1.60  110EriePA
4,958  0.5  0.50  0.30.30Not providedPA
7,212  1.8  1.40  1.210ScrantonPA
6,694  2.6  1.90  1.61.40LancasterPA
7,162  1.2  1.20  0.70.70New CastlePA
7,200  2.6  2.40  1.91.50Wilkes-BarrePA
7,306  1.1  1.10  0.80.80NorristownPA
7,308  2.1  20  1.61.60FreemansburgPA
6,160  3.7  2.70  1.71.30PhiladelphiaPA
1,764  1.3  1.10  0.70.70PhiladelphiaPA
7,094  1.3  1.20  1.21.10CharleroiPA
3,795  4.2  2.80  2.32.30BayamonPR
5,854  3.8  3.70  2.42.30San JuanPR
6,421  3.9  3.30  1.71.40San JuanPR
6,420  1.5  1.40  10.90East ProvidenceRI
8,714  2.3  20  1.41.30GreenvilleSC
8,561  0.9  0.80  0.50.50Not providedSC
8,747  3.2  3.20  2.41.90NashvilleTN
6,248  1.7  1.50  110KingsportTN
8,514  3.2  2.50  1.51.40MemphisTN
6,824  1.6  1.50  0.80.70BrownsvilleTX
5,201  1.7  1.70  1.41.30DallasTX
7,170  7  6.10  4.93.20El PasoTX
6,895  2.9  2.70  1.51.50El PasoTX
7,198  5  4.80  31.80El PasoTX
6,712  7.3  60  4.22.40El PasoTX
7,202  6.7  6.60  4.83.90El PasoTX
6,985  4.3  40  32.80El PasoTX
7,040  3.5  3.40  1.71.70LaredoTX
7,176  2.5  2.10  1.41.30El PasoTX
6,875  2.9  2.70  1.71.50Not providedTX
6,310  3.8  3.70  2.72.30HoustonTX
6,258  2.1  1.90  1.61.30HoustonTX
6,322  8.9  8.10  5.95.20HoustonTX
5,662  1.4  1.40  10.80HoustonTX
6,863  1.7  1.50  0.90.60Deer ParkTX
5,594  1.8  1.70  10.70NederlandTX
7,105  0.8  0.30  0.30.30WacoTX
7,080  1.7  1.70  1.110Fort WorthTX
7,205  1.8  1.40  10.90ArlingtonTX
7,241  0.7  0.60  0.40.40AustinTX
6,942  3.2  2.90  1.41.30LaredoTX
6,154  0.9  0.90  0.50.50Not providedTX
6,309  2.5  2.40  1.91.40San AntonioTX
7,199  7.8  4.70  2.72.60San AntonioTX
7,235  3.2  2.90  1.61.60SocorroTX
6,469  3  2.90  2.22.10Not providedUT
6,297  4.1  3.60  2.42.30Salt Lake CityUT
5,77627.924.20  8.86.40OgdenUT
6,333  5  3.90  1.61.50ProvoUT
5,744  3.3  3.30  220OgdenUT
2,125  3.7  3.30  1.81.80West ValleyUT
5,996  1.1  10  0.90.80AnnandaleVA
6,479  1.3  1.20  10.80RichmondVA
6,469  1.7  1.60  1.21.10Not providedVA
7,175  1.4  1.40  1.210Not providedVA
7,133  1.9  1.90  1.91.80FranconiaVA
6,489  2  20  1.51.40RoanokeVA
7,097  2  20  1.51.50McleanVA
6,365  1.9  1.90  1.21.20AlexandriaVA
6,439  4.2  4.10  1.61.30HamptonVA
6,487  4.7  4.50  2.21.90NorfolkVA
6,218  3.1  2.70  2.11.80RutlandVT
6,194  1.9  1.80  1.21.10BurlingtonVT
7,232  3.4  3.10  2.31.90BellevueWA
5,468  0.3  0.30  0.30.30Not providedWA
6,885  1.4  1.20  0.90.90SeattleWA
7,140  4.3  4.10  2.42.40SpokaneWA
7,674  0.5  0.50  0.40.40Not providedWI
6,541  3.9  3.50  2.32.20WeirtonWV
6,532  2.7  2.70  1.81.70WeirtonWV
6,449  4.5  4.30  2.92.30WeirtonWV
6,984  0.9  0.80  0.60.40Not providedWY
6,361  0.9  0.90  0.70.70Not providedWY
a

Post office state abbreviations are used.

Source: EPA 2009i

From: 6, POTENTIAL FOR HUMAN EXPOSURE

Cover of Toxicological Profile for Carbon Monoxide
Toxicological Profile for Carbon Monoxide.
Wilbur S, Williams M, Williams R, et al.

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