21 CFR §1.1151

1. (a)The method of analysis used to conduct food testing under this subpart must be:
   1. (1)Fit for purpose;
   2. (2)Within the laboratory's scope of LAAF-accreditation;
   3. (3)Appropriately validated for use in such food testing, in accordance with paragraph (c) of this section; and
   4. (4)Appropriately verified by the LAAF-accredited laboratory for use in such food testing, in accordance with paragraph (d) of this section.
2. (b)Food testing must be conducted using the specified method:
   1. (1)Under § 1.1107(a)(1), if the Federal Food, Drug, and Cosmetic Act or implementing regulations prescribe a test method.
   2. (2)Under § 1.1107(a)(2), if the directed food laboratory order prescribes a test method.
3. (c)
   1. (1)A LAAF-accredited laboratory must validate methods in accordance with the requirements of § 1.1138(a).
   2. (2)A LAAF-accredited laboratory performing validation of a method under this subpart must record the information required by § 1.1138(a) and the supporting analytical data.
4. (d)
   1. (1)Before a LAAF-accredited laboratory conducts food testing under this subpart using a method for a specific intended use for which the method has been validated, but for which the LAAF-accredited laboratory has not previously applied the method under this subpart, the LAAF-accredited laboratory must have verified it can properly perform the method for the specific intended use.
   2. (2)A LAAF-accredited laboratory performing verification of a method under this subpart must record the method that is the subject of the verification, the intended purpose of the analysis, the results of the verification, the procedure used for the verification, supporting analytical data, and whether the LAAF-accredited laboratory is able to properly perform the method.
5. (e)A LAAF-accredited laboratory may submit a written request to FDA requesting permission to use a method outside of its scope of LAAF-accreditation for food testing. FDA may approve the request if both following conditions are satisfied:
   1. (1)A new method or methodology has been developed and validated but no reasonably available laboratory has been LAAF-accredited to perform such method or methodology, and
   2. (2)The use of such method is necessary to prevent, control, or mitigate a food emergency or foodborne illness outbreak.