Site Feedback

Title 40

Displaying title 40, up to date as of 7/08/2026. Title 40 was last amended 7/08/2026.
eCFR Content

The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. It is not an official legal edition of the CFR.

Learn more about the eCFR, its status, and the editorial process.

§ 766.27 Congeners and LOQs for which quantitation is required.

Quantitation at the target LOQ shown for each of the following HDDs/HDFs which may be present in the chemical substances is required for the chemical substances listed under § 766.25. Analysis must take place for either chlorinated or brominated dibenzodioxins or dibenzofurans, whichever is predominantly expected to occur in the chemical substance to be tested. Only chlorinated and brominated congeners need be quantified; for chemical substances containing predominantly chlorine atoms, only congeners totally chlorinated at the numbered positions need be quantified; for chemical substances containing predominantly bromine atoms, only congeners totally brominated at the numbered positions need be quantified.

Chlorinated dioxins Brominated dioxins LOQ
2,3,7,8-TCDD 2,3,7,8-TBDD 0.1 ppb.
1,2,3,7,8-PeCDD 1,2,3,7,8-PeBDD 0.5 ppb.
1,2,3,4,7.8-HxCDD 1,2,3,4,7,8-HxBDD 2.5 ppb.
1,2,3,6,7,8-HxCDD 1,2,3,6,7,8-HxBDD 2.5 ppb.
1,2,3,7,8,9-HxCDD 1,2,3,7,8,9-HxBDD 2.5 ppb.
1,2,3,4,6,7,8-HpCDD 1,2,3,4,6,7,8-HpBDD 100 ppb.
2,3,7,8-TCDF 2,3,7,8-TBDF 1 ppb.
1,2,3,7,8-PeCDF 1,2,3,7,8-PeBDF 5 ppb.
2,3,4,7,8-PeCDF 2,3,4,7,8-PeBDF 5 ppb.
1,2,3,4,7,8-HxCDF 1,2,3,4,7,8-HxBDF 25 ppb.
1,2,3,6,7,8-HxCDF 1,2,3,6,7,8-HxBDF 25 ppb.
1,2,3,7,8,9-HxCDF 1,2,3,7,8,9-HxBDF 25 ppb.
2,3,4,6,7,8-HxCDF 2,3,4,6,7,8-HxBDF 25 ppb.
1,2,3,4,6,7,8-HpCDF 1,2,3,4,6,7,8-HpBDF 1 ppm.
1,2,3,4,7,8,9-HpCDF 1,2,3,4,7,8,9-HpBDF 1 ppm.