Table 2

Summary of risk criteria related to CO measurements, risk categories, and 5 exposure categories

Risk
category
Exposure
category
Risk criteria (all emissions of CO)
% (N)

Little or none
1
CO emissions from all appliances < 26 ppm
69% (409)
Low
2
Cooker emissions > 26 ppm
Gas fire spilling any CO
CO in boiler flue gases (room sealed) > 1000 ppm
Boiler spilling any CO
Poorly positioned flue terminal and flue gases of boiler > 52 ppm
Boiler rated ID (any reason) and flue gases > 108 ppm
19% (111)
Medium
3
Cooker emissions > 52 ppm CO
Gas fire spilling > 26 ppm CO
Boiler spilling > 26 ppm
Poorly positioned flue terminal and flue gases of boiler > 104 ppm
7% (42)
High
4
Cooker emissions > 104 ppm
Gas fire spilling > 52 ppm CO
Boiler spilling > 52 ppm
Poorly positioned flue terminal and flue gases of boiler > 208 ppm
4% (22)
Very High
5
Cooker emissions > 208 ppm
Gas fire spilling > 104 ppm CO
Boiler spilling > 104 ppm
Boiler flue gases (open flued) > 1000 ppm
Poorly positioned flue terminal and flue gases of boiler > 416 ppm
2% (13)

Total


100% (597)

Croxford et al. Environmental Health 2008 7:34   doi:10.1186/1476-069X-7-34