# The Control of Major Accident Hazards Regulations 2015, Paragraph 20


Polychlorodibenzofurans and polychlorodibenzodioxins.
The quantities of polychlorodibenzofurans and polychlorodibenzodioxins are calculated using the following factors:
1 Van den Berg et al: The 2005 World Health Organisation Re-evaluation of Human and Mammalian Toxic Equivalency Factors for Dioxins and Dioxin like Compounds.
WHO 2005 TEF 1
2,3,7,8-TCDD
1
2,3,7,8-TCDF
0.1
1,2,3,7,8-PeCDD
1
2,3,4,7,8-PeCDF
0.3
1,2,3,7,8-PeCDF
0.03
1,2,3,4,7,8-HxCDD
0.1
1,2,3,6,7,8-HxCDD
0.1
1,2,3,4,7,8-HxCDF
0.1
1,2,3,7,8,9-HxCDD
0.1
1,2,3,7,8,9-HxCDF
0.1
1,2,3,6,7,8-HxCDF
0.1
1,2,3,4,6,7,8-HpCDD
0.01
2,3,4,6,7,8-HxCDF
0.1
OCDD
0.0003
1,2,3,4,6,7,8-HpCDF
0.01
1,2,3,4,7,8,9-HpCDF
0.01
OCDF
0.0003
T = tetra, Pe = penta, Hx = hexa, Hp = hepta, O = octa

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Source: https://www.legislation.gov.uk/uksi/2015/483/schedule/1/paragraph/20 (the official version)
Page: https://openlegislation.uk/control-of-major-accident-hazards-regulations-2015/schedule-1/paragraph-20
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.