Ambient air quality criteria

Ambient air quality criteria, or standards, are concentrations of pollutants in the air, and typically refer to outdoor air. The criteria are specified for a variety of reasons including for the protection of human health, buildings, crops, vegetation, ecosystems, as well as for planning and other purposes. There is no internationally accepted definition but usually "standards" have some legal or enforcement aspect, whereas "guidelines" may not be backed by laws. "Criteria/criterion" can be used as a generic term to cover standards and guidelines.

Various organisations have proposed criteria e.g. WHO, EU, US EPA. These criteria are often similar - but not always, even if they are proposed for the same purpose (e.g. the protection of human health).

Specifying the criteriaEdit

It is important for any numerical standard that averaging period, unit, and statistical measure are given (e.g. the 98th percentile of hourly means measured over a calendar year in micrograms per cubic metre (μg/m3)). Without these there is no common ground for a given criterion, making it confusing or even meaningless. Criteria can be set in different units (e.g. μg/m3, parts per billion by volume (ppbv), parts per billion by mass (ppb (mass)), parts per million (ppm)) and it is possible to convert between all of these units if the molecular mass of the pollutant and the temperature are known. Different standard temperatures are used throughout the world and so it is important to state the temperature of conversion (if relevant). Most pollutants have ambient criteria in the parts per billion (ppb) or μg/m3 range. Some have smaller units (e.g. dioxins are often in pico grams /m3); others have larger units (e.g. carbon monoxide (CO) in mg/m3). Particle pollution (e.g. PM10, PM1.0) is specified in units of mass (e.g. μg/m3) and not in units of volume (ppmv).

In the EU, the pollutants and their criteria are specified in Directive 2008/50/EC.

The criteriaEdit

Below is a list of available air quality criteria around the world. There is a lot of cross referencing between organizations (e.g. the International Finance Corp (IFC)) that have their own criteria but ultimately, many criteria are based on those specified by the World Health Organization (WHO). It is important when complying with ambient air quality criteria to check the direct reference as well. Not all related caveats/controlling parameters of a criterion can be put in the table, and therefore those specified below are mostly those that most monitoring agencies specify. These agencies also list whether criteria must be monitored in a specific way to fit with compliance measures.

Pollutant Abbr. Value Units Averaging Period Statistical Measure # exceedences Organisation Status Applicability Notes
Nitrogen dioxide NO2 40 μg/m3 Annual1 Mean None WHO [1] Guideline Global
Nitrogen dioxide NO2 200 μg/m3 1 hour Mean None WHO [1] Guideline Global
Nitrogen dioxide NO2 40 μg/m3 Annual Mean None EU [2] Limit Value EU Member States Calendar Year
Nitrogen dioxide NO2 53 ppb Annual Mean None US EPA[3] Legal United States Primary and Secondary
Nitrogen dioxide NO2 100 μg/m3 Annual Yrly mean of daily None SCENR [4] Legal Qatar Calendar Year
Nitrogen dioxide NO2 40 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China
Nitrogen dioxide NO2 100 μg/m3 Daily Mean New Zealand Ministry for the Environment[6] Guideline New Zealand Calendar Year
Nitrogen dioxide NO2 113 μg/m3 Daily Daily mean of hourly None Japanese Ministry of Environment [7] Legal Japan Quoted as 0.06 ppm
Nitrogen dioxide NO2 150 μg/m3 Daily 99.7%ile 1 day/yr SCENR [4] Legal Qatar Calendar Year
Nitrogen dioxide NO2 80 μg/m3 Daily Mean None Chinese Ministry of Ecology and Environment[5] Legal China
Nitrogen dioxide NO2 100 ppb 1 hour 98% of 1-hour daily maximum concentrations, averaged over 3 years None US EPA[3] Legal United States Primary
Nitrogen dioxide NO2 40 μg/m3 Annual Mean None India Central Pollution Control Board (CPCB) [8] Legal India Calendar Year
Nitrogen dioxide NO2 30 μg/m3 Annual Mean None India Central Pollution Control Board(CPCB) [8] Legal India - Ecologically sensitive areas Calendar Year
Nitrogen dioxide NO2 80 μg/m3 24 hour2 Mean None India Central Pollution Control Board (CPCB) [8] Legal India Calendar Year
Nitrogen dioxide NO2 200 μg/m3 1 hour 99.79%ile 18 hrs/yr EU [2] Limit value EU Member States Calendar Year
Nitrogen dioxide NO2 200 μg/m3 1 hour Mean 9/yr New Zealand Ministry for the Environment[9] Legal New Zealand Calendar Year
Nitrogen dioxide NO2 400 μg/m3 1 hour 99.7%ile 26 hrs/yr SCENR [4] Legal Qatar Calendar Year
Nitrogen dioxide NO2 200 μg/m3 1 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China
Pollutant Abbr. Value Units Averaging Period Statistical Measure # exceedences Organisation Status Applicability Notes
Sulphur dioxide SO2 75 ppb 1 hour 99% of 1-hour daily maximum concentrations, averaged over 3 years None US EPA[3] Legal United States* Primary
Sulphur dioxide SO2 500 ppb 3 hours Mean Once per year US EPA[3] Legal United States Secondary quoted as 0.5 ppm
Sulphur dioxide SO2 20 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
Sulphur dioxide SO2 60 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
Sulphur dioxide SO2 50 μg/m3 Daily Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
Sulphur dioxide SO2 20 μg/m3 Annual Mean None India Central Pollution Control Board (CPCB) [8] Legal India - Ecologically sensitive areas
Sulphur dioxide SO2 50 μg/m3 Annual Mean None India Central Pollution Control Board (CPCB) [8] Legal India
Sulphur dioxide SO2 80 μg/m3 24 hour Mean None India Central Pollution Control Board (CPCB) [8] Legal India
Sulphur dioxide SO2 150 μg/m3 Daily Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
Sulphur dioxide SO2 150 μg/m3 1 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
Sulphur dioxide SO2 500 μg/m3 1 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
Sulphur dioxide SO2 125 μg/m3 24 hour Any 24 hour period None WHO [1] Interim Target (IT) 1 Global Was the guideline in 2000
Sulphur dioxide SO2 50 μg/m3 24 hour Any 24 hour period None WHO [1] Interim Target (IT) 2 Global Calendar Year (1 Jan - 31 Dec)
Sulphur dioxide SO2 125 μg/m3 24 hour Any 24 hour mean None WHO [1] Interim Target (IT) 1 Global
Sulphur dioxide SO2 50 μg/m3 24 hour Any 24 hour mean None WHO [1] Interim Target (IT) 2 Global
Sulphur dioxide SO2 20 μg/m3 24 hour Any 24 hour mean None WHO [1] Guideline Global
Sulphur dioxide SO2 500 μg/m3 10 minute Any 10 minute mean None WHO [1] Guideline Global
Sulphur dioxide SO2 1300 μg/m3 1 hour 99.99%ile 1 hr/year Ras Laffan Legal Qatar Calendar Year
Sulphur dioxide SO2 350 μg/m3 1 hour Mean 9/yr New Zealand Ministry for the Environment[6] Legal New Zealand
Sulphur dioxide SO2 570 μg/m3 1 hour Mean None New Zealand Ministry for the Environment[6] Legal New Zealand
Sulphur dioxide SO2 120 μg/m3 24 hour Average New Zealand Ministry for the Environment[6] Guideline New Zealand
Abbr. Value Units Averaging Period Statistical Measure # exceedences Organisation Status Applicability Notes
PM10 "Coarse Particulate Matter" 150 μg/m3 24 hour Average over 3 years Once per year US EPA[3] Legal United States Primary and Secondary
PM10 125 μg/m3 24 hour 99th %ile 3 days/yr WHO [1] Guideline Global
PM10 50 μg/m3 24 hour Mean None WHO [1] Guideline Global
PM10 20 μg/m3 Annual Mean None WHO [1] Guideline Global
PM10 60 μg/m3 Annual Mean None India Central Pollution Control Board (CPCB) [8] Legal India
PM10 10 μg/m3 24 hour Mean None India Central Pollution Control Board (CPCB) [8] Legal India
PM10 50 μg/m3 24 hour Mean 1/yr New Zealand Ministry for the Environment[6] Legal New Zealand
PM10 40 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
PM10 70 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
PM10 50 μg/m3 24 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
PM10 150 μg/m3 24 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
PM2.5 "Fine Particulate Matter" 35 μg/m3 24 hour 98% averaged over 3 years None US EPA[3] Legal United States Primary and Secondary
PM2.5 25 μg/m3 24 hour Any 24 hr mean None WHO [1] Guideline Global
PM2.5 60 μg/m3 24 hour mean None India Central Pollution Control Board (CPCB) [8] Legal India
PM2.5 40 μg/m3 Annual Mean None India Central Pollution Control Board (CPCB) [8] Legal Global
PM2.5 75 μg/m3 24 hour Any 24 hr mean None WHO [1] Interim target (IT) 1 Global
PM2.5 50 μg/m3 24 hour Any 24 hr mean None WHO [1] Interim target (IT) 2 Global
PM2.5 37.5 μg/m3 24 hour Any 24 hr mean None WHO [1] Interim target (IT) 3 Global
PM2.5 12.0 μg/m3 Annual Annual mean over 3 years None US EPA[3] Legal United States Primary
PM2.5 15 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
PM2.5 35 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
PM2.5 15.0 μg/m3 Annual Annual mean over 3 years None US EPA[3] Legal United States Secondary
PM2.5 10 μg/m3 Annual Mean None WHO [1] Guideline Global
PM2.5 25 μg/m3 24 hour Mean None WHO [1] Guideline Global
PM2.5 25 μg/m3 Annual Mean None WHO [1] Interim target (IT) 2 Global
PM2.5 15 μg/m3 Annual Mean None WHO [1] Interim target (IT) 3 Global
PM2.5 35 μg/m3 24 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
PM2.5 75 μg/m3 24 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
Pollutant Abbr. Value Units Averaging Period Statistical Measure # exceedences Organisation Status Applicability Notes
Ozone O3 0.07 ppm 8 hours Annual 4th highest daily maximum 8-hour concentration, averaged over 3 years 3/yr US EPA[3] Legal United States* Primary and Secondary
Ozone O3 100 μg/m3 8 hours Any 8 hour mean None WHO [1] Guideline Global
Ozone O3 100 μg/m3 8 hours Mean None India Central Pollution Control Board (CPCB) [8] Guideline India
Ozone O3 180 μg/m3 1 hour Mean None India Central Pollution Control Board (CPCB) [8] Legal India
Ozone O3 160 μg/m3 8 hours Any 8 hour mean None WHO [1] Interim target Global
Ozone O3 100 μg/m3 8 hours Daily maximum 8-hour averaged concentration None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
Ozone O3 160 μg/m3 8 hours Daily maximum 8-hour averaged concentration None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
Ozone O3 160 μg/m3 1 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 1 Areas
Ozone O3 200 μg/m3 1 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China Category 2 Areas
Ozone O3 235 μg/m3 1 hour 99.9% 8 hrs/yr SCENR [4] Legal Qatar Calendar Year
Ozone O3 120 μg/m3 8 hours 99.8% 2x8hrs/yr SCENR [4] Legal Qatar Calendar Year
Ozone O3 150 μg/m3 1 hour Mean None New Zealand Ministry for the Environment[6] Legal New Zealand
Pollutant Abbr. Value Units Averaging Period Statistical Measure # exceedences Organisation Status Applicability Notes
Carbon monoxide CO 35 ppm 1 hour Mean 1/yr US EPA[3] Legal United States Primary
Carbon monoxide CO 40 mg/m3 1 hour Maximum None SCENR [4] Legal Qatar Calendar Year
Carbon monoxide CO 4 mg/m3 1 hour Maximum None India Central Pollution Control Board (CPCB) [8] Legal India
Carbon monoxide CO 2 mg/m3 8 hour Maximum None India Central Pollution Control Board (CPCB) [8] Legal India
Carbon monoxide CO 10 mg/m3 1 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China
Carbon monoxide CO 9 ppm 8 hour Mean 1/yr US EPA[3] Legal United States Primary
Carbon monoxide CO 10 mg/m3 8 hour Maximum None SCENR [4] Legal Qatar Calendar Year
Carbon monoxide CO 10 mg/m3 8 hour Mean 1/yr New Zealand Ministry for the Environment[6] Legal New Zealand
Carbon monoxide CO 30 mg/m3 1 hour Mean 1/yr New Zealand Ministry for the Environment[6] Legal New Zealand
Carbon monoxide CO 4 mg/m3 24 hour Mean None Chinese Ministry of Ecology and Environment[5] Legal China
Pollutant Abbr. Value Units Averaging Period Statistical Measure # exceedences Organisation Status Applicability Notes
Lead Pb 0.15 μg/m3 3 month Rolling 3 month average None US EPA[3] Legal United States Primary and Secondary
Lead Pb 0.5 μg/m3 Annual Mean None Chinese Ministry of Ecology and Environment[5] Legal China
Lead Pb 0.5 μg/m3 Annual Mean None India Central Pollution Control Board (CPCB) [8] Legal India
Lead Pb 1 μg/m3 24 hours Mean None India Central Pollution Control Board (CPCB) [8] Legal India
Lead Pb 1 μg/m3 Season Mean None Chinese Ministry of Ecology and Environment[5] Legal China

FootnotesEdit

[1] Annual arithmetic mean of a minimum of 104 measurements in a year at a particular site, such as taken twice weekly as uniform 24-hour samples.

[2] 24/8/1 hourly monitored values, as applicable, shall be complied with 98% of the time, they may exceed the limits but not on two consecutive days of monitoring.

See alsoEdit

ReferencesEdit

  1. ^ a b c d e f g h i j k l m n o p q r s t u Air quality guidelines - global update 2005 www.who.int/phe/health_topics/outdoorair/outdoorair_aqg/en/
  2. ^ a b DIRECTIVE 2008/50/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 21 May 2008 on ambient air quality and cleaner air for Europe http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32008L0050
  3. ^ a b c d e f g h i j k l EPA, OAR, US. "NAAQS Table | US EPA". US EPA. Retrieved 2018-11-05.
  4. ^ a b c d e f g Supreme Council for Environment and Natural Resources, Executive Bye-law for the Environment Protection Law Issued via the Decree Law No. 30 for the Year 2002, Annex 3"
  5. ^ a b c d e f g h i j k l m n o p q r s t u v w x y "GB 3095-2012" (PDF).
  6. ^ a b c d e f g h "Nitrogen dioxide | Ministry for the Environment". www.mfe.govt.nz. Retrieved 2017-04-05.
  7. ^ Japanese Ministry of Environment, Environmental Quality Standards - Air Quality https://www.env.go.jp/en/air/aq/aq.html
  8. ^ a b c d e f g h i j k l m n o p India Central Pollution Control Board - Air Quality Standards http://cpcb.nic.in/air-quality-standard/
  9. ^ "Resource Management (National Environmental Standards for Air Quality) Regulations 2004 (SR 2004/309) (as at 17 October 2014) – New Zealand Legislation". www.legislation.govt.nz. Retrieved 2017-04-05.