# Third Commission Directive of 27 September 1983 on the approximation of the laws of the Member States relating to methods of analysis necessary for checking the composition of cosmetic products (83/514/EEC), Division 9.1: Calculating a response factor of a substance ‘p’ relative to a substance ‘a’ selected as an internal standard

Extent: E+W+S+N.I.

Let the first substance be ‘p’, where:
kp its response factor,
mp its mass in the mixture,
Ap its peak area.
Let the second substance be ‘a’, where:
ka its response factor (made equal to unity),
Ma its mass in the mixture,
Aa its peak area,
then:
k p = m p × A a M a × A p
As examples the following response factors have been obtained (for chloroform: k = l):
Dichloromethane: k1 = 0,78 ± 0,03
1,1,1-trichloroethane: k2 = 1,00 ± 0,03

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Source: https://www.legislation.gov.uk/eudr/1983/514/annex/division/9/division/9.1 (the official version)
Page: https://openlegislation.uk/eu-directive-1983-514/annex/division-9/division-9.1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.