To demonstrate compliance with the microbiological standards required in GMP environments it is necessary to monitor the number of microbes in the air and on the surfaces. The microbiological standard of air may be monitored by active or passive sampling. The microbiological standard of surfaces may be monitored by the use of contact plates or swab samples.

The limits for active and passive air samples and for contact plates are prescribed in ‘Rules and Guidance for Pharmaceutica lManufacturers and Distributors’ (Annex 1), and ‘Quality Assurance of As

eptic Preparation Services. These publications do not describe the number or location of samples to be taken.

This document provides guidance on the minimum number of samples to be taken and their locations in GMP environments. Gas sterilised isolators are not covered in this document.