<61> Microbial Enumeration Tests

Type of Posting: Notice of Adoption of Harmonized Standard

Posting Date: 26-Apr-2024

Official Date: 1-May-2025

Expert Committee: General Chapters – Microbiology (GCM)

Coordinating Pharmacopoeia: European Pharmacopeia

A correction to the harmonized standard for <61> Microbial Enumeration Tests has been approved by the Pharmacopeial Discussion Group (PDG) as described in its PDG Rev. 1 sign-off cover sheet. Having reached Stage 4 (former Stage 6) of the PDG process, the general chapter of <61> Microbial Enumeration Tests has been formally approved by the USP General Chapters – Microbiology Expert Committee in accordance with the Rules and Procedures of the 2020-2025 Council of Experts.

The changes from the existing USP-NF general chapter include the following:

  • Section 4-6 ‘Results and interpretation’, clarification of the reading procedure to be performed when verifying the suitability of the membrane filtration method.

General Chapter <61> Microbial Enumeration Tests will become official on May 1, 2025.

Should you have any questions, please contact Leslie Furr, M.S. (301-692-3695 or leslie.furr@usp.org). For any questions about the PDG and its processes, please contact Richard Lew (240-221-2060 or rll@usp.org).