Benzene: 16.25 micrograms per cubic metre or less, when expressed as a running annual mean,31 December 2003,
Benzene: 5 micrograms per cubic metre or less, when expressed as an annual mean , 31 December 2010 ,
1, 3 -Butadiene: 2.25 micrograms per cubic metre or less, when expressed as a running annual mean,31 December 2003,
Carbon monoxide:  10 milligrams per cubic metre or less, when expressed as a maximum daily running 8 hour mean,31 December 2003,
Nitrogen dioxide: 200 micrograms per cubic metre or less, when expressed as an hourly mean, not to be exceeded more than 18 times a year,31 December 2005,
Nitrogen dioxide: 40 micrograms per cubic metre or less, when expressed as an annual mean,31 December 2005,
Lead: 0.5 micrograms per cubic metre or less, when expressed as an annual mean,31 December 2004,
Lead: 0.25 micrograms per cubic metre or less, when expressed as an annual mean,31 December 2008,
PM 10 : 50 micrograms per cubic metre or less, when expressed as a 24 hour mean, not to be exceeded more than 35 times a year,31 December 2004,
PM 10 40 micrograms per cubic metre or less, when expressed as an annual mean,31 December 2004,
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,31 December 2004,
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,31 December 2004,
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,31 December 2005,