The Air Quality Standards Regulations 2007

Benzene and carbon monoxide

This section has no associated Explanatory Memorandum

6.  The data quality objectives set out in the following table, for allowed uncertainty of assessment methods, of minimum time coverage and of data capture of measurement are provided to guide quality assurance programmes—

BenzeneCarbon monoxide
Fixed measurements
Uncertainty25%15%
Minimum data capture90%90%
Minimum time coverage35% urban background and traffic sites (distributed over the year to be representative of various conditions for climate and traffic); 90% industrial sites
Indicative measurements
Uncertainty30%25%
Minimum data capture90%90%
Minimum time coverage14% (one day’s measurement a week at random, evenly distributed over the year, or eight weeks evenly distributed over the year)14% (one measurement a week at random, evenly distributed over the year, or eight weeks evenly distributed over the year)
Modelling
Uncertainty:
Eight-hour averages50%
Annual averages50%
Objective estimation
Uncertainty100%75%