Air Pollution in Bristol for Wed 23 Aug 2017:

LOW
MODERATE
HIGH
VERY HIGH

The overall air pollution in Bristol: value 1 out of 10 (1 = lowest, 10 = highest)D |
 

Frequently asked questions

What are the key air quality pollutants?

The Air Quality Regulations 2000 and Air Quality (Amendment)  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
as above
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
as above
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)
as above
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
as above
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.

See also:
Please click on a question below to see the answer on the left ...
Pollution glossary
2
Benzene (C6H6)
5
Ozone (O3)
6
PM10
8
Solar radiation
10
Toluene
11
Xylene