Table 7.1. EU data was from European Commission Air Quality Standards  http://ec.europa.eu/environment/air/quality/index.htm.   WHO values were obtained from footnote 3 and updated values (in bold) from WHO Air quality guidelines http://apps.who.int/iris/bitstream/10665/69477/1/WHO_SDE_PHE_OEH_06.02_eng.pdf.

Table 7.2 Data on particulate matter from the WHO urban ambient air pollution database – 2016 update (in bold):  http://www.who.int/phe/health_topics/outdoorair/databases/cities/en/

Table 7.3. The United States Environmental Protection Agency, Technical assistance document for reporting of daily air quality – the Air Quality Index, EPA-454/B-13-001, 2013.  https://www3.epa.gov/airnow/aqi-technical-assistance-document-dec2013.pdf, accessed November, 2016. Updated to https://airnow.gov/

Footnote 10.  http://www.euro.who.int/__data/assets/pdf_file/0015/123072/AQG2ndEd_6_2_asbestos.PDF

Additional Resources

4. Air Now, International Air Quality. http://www.airnow.gov/. Note: Click on ‘international’ at the bottom of the home page. This takes you to a listing of many national websites where air quality information is available; some countries report data as ongoing real-time information as well as archiving previous data.

5. World Health Organization, Air quality guidelines – global update, 2005, and Air quality guidelines for Europe 2nd Ed. 2000. Both available online from http://www.euro.who.int/, accessed under publications, Search: ‘air’

Problem 16. The website https://waqi.info/ gives real time data on important air quality parameters for many cities on all continents around the world.