# The Air Quality (Scotland) Regulations 2000, Schedule: AIR QUALITY OBJECTIVES TABLE Extent: S Column 1 Column 2 Column 3 Substance Air Quality Objectives Prescribed Date 1 Benzene 16.25 micrograms per cubic metre or less, when expressed as running annual mean 31st December 2003 1A Benzene 3.25 micrograms per cubic metre or less, when expressed as a running annual mean 31st December 2010 2 1,3-Butadiene 2.25 micrograms per cubic metre or less, when expressed as a running annual mean 31st December 2003 3 Carbon monoxide 10 milligrams per cubic metre or less, when expressed as a running 8 hour mean 31st December 2003 4 Lead 0.5 micrograms per cubic metre or less, when expressed as an annual mean 31st December 2004 5 Lead 0.25 micrograms per cubic metre or less, when expressed as an annual mean 31st December 2008 6 Nitrogen dioxide 200 micrograms per cubic metre, when expressed as an hourly mean, not to be exceeded more than 18 times a year 31st December 2005 7 Nitrogen dioxide 40 micrograms per cubic metre or less, when expressed as an annual mean 31st December 2005 7A PM2.5 10 micrograms per cubic metre or less, when expressed as an annual mean 31st December 2020 8 PM10 50 micrograms per cubic metre or less, when expressed as a 24 hour mean, not to be exceeded more than 35 times a year 31st December 2004 8A PM10 50 micrograms per cubic metre or less when expressed as a 24 hour mean, not to be exceeded more than 7 times a year 31st December 2010 9 PM10 40 micrograms per cubic metre or less, when expressed as an annual mean 31st December 2004 9A PM10 18 micrograms per cubic metre or less, when expressed as an annual mean 31st December 2010 10 Sulphur dioxide 350 micrograms per cubic metre or less, when expressed as an hourly mean, not to be exceeded more than 24 times a year 31st December 2004 11 Sulphur dioxide 125 micrograms per cubic metre or less, when expressed as a 24 hour mean, not to be exceeded more than 3 times a year 31st December 2004 12 Sulphur dioxide 266 micrograms per cubic metre or less, when expressed as a 15 minute mean, not to be exceeded more than 35 times a year. 31st December 2005 --- Source: https://www.legislation.gov.uk/ssi/2000/97/schedule (the official version) Page: https://openlegislation.uk/air-quality-scotland-regulations-2000/schedule Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.