Font size too small?   Increase Font size | Decrease font size | See other Accessibility Options.
Index Banded Annual Totals for Swansea:
LOW
228 days
MODERATE
63 days
HIGH
3 days
VERY HIGH
1 day

Frequently asked questions

What are the key air quality pollutants?

The Air Quality (Wales) Regulations 2000 and Air Quality (Amendment)(Wales)  Regulations 2002 set air quality objectives for the 7 key pollutants contained within the UK National Air Quality Strategy. The current air quality objectives set in regulation are listed below:

Pollutant Concentration Measured as Examples of sources Permitted number of exceedences allowed Compliance date
Benzene*
(C6 H6)
16.25 g/m3 (5ppb) Running annual mean Constituent of petrol emitted as un-burnt fuel or through evaporation (motor vehicles etc). Also present in cigarette smoke.
n/a
31 Dec 2003
5 g/m3 (1.5ppb) Annual mean
n/a
31 Dec 2010
1,3-Butadiene* 2.25 g/m3 (1 ppb) Running annual mean Used in the manufacture of synthetic chemicals and rubber. Also present in cigarette smoke.
n/a
31 Dec 2003
Carbon monoxide (CO) 10.00 m g/m3 (8.6ppm) Maximum daily running 8 hour mean Vehicle emissions, inefficient combustion of most fuels including gas, coal and oil.
n/a
31 Dec 2003
Nitrogen dioxide
(NO2)
200 g/m3 (105ppb) 1 hour mean Combustion processes particularly vehicle emissions.
18
31 Dec 2005
40 g/m3 (21ppb) Annual mean
n/a
31 Dec 2005
Lead
(pB)
0.5 g/m3 Annual mean Main source in ambient air from leaded petrol (4 Star)
n/a
31 Dec 2004
0.25 g/m3 Annual mean ( by 2008)
n/a
31 Dec 2008
Particles
(PM 10)
50 g/m3 24 hour mean Many sources but particularly from diesel vehicle emissions in towns and cities.
35
31 Dec 2004
40 g/m3 Annual mean
n/a
31 Dec 2004
Sulphur dioxide
(SO2)
350 g/m3 (132 ppb) 1 hour mean Mainly from combustion of fossil fuels.
24
31 Dec 2004
125 g/m3 (47 ppb) 24 hour mean
3
31 Dec 2004
266 g/m3 (100 ppb) 15 minute mean
35
31 Dec 2005
Key
g/m3 = (microgram per cubic metre of air)
mg/m3 = (milligram per cubic metre of air)
ppb = (part per billion) or one part of the pollutant per one billion parts of air.
ppm = (part per million) or one part of the pollutant per million parts of air.

For more information on air quality guidelines and statistics please visit the links section.

Pollution glossary: