Cleanroom Monitoring According to Annex 1


For anyone involved in the manufacturing of sterile medicinal products, the recent PIC/S GMP version 17 Annex 1 guidelines are nothing short of a bible. They delineate the rigorous standards necessary to maintain product sterility. One such crucial aspect outlined in these guidelines is cleanroom monitoring. In this blog, we aim to elucidate the directives set by Annex 1 for cleanroom monitoring and how best to comply with them.

What is Cleanroom Monitoring?

In a nutshell, cleanroom monitoring is a process that ensures the cleanroom environment stays within predefined limits of cleanliness, temperature, humidity, and pressure. By continuously tracking these parameters, cleanroom monitoring aids in minimizing contamination risks that could compromise the sterility of the products manufactured.

Cleanroom Monitoring as per Annex 1

The Annex 1 guidelines mandate a risk-based approach to cleanroom monitoring. The guidelines emphasize the need for a robust environmental monitoring system that reflects the actual conditions during manufacturing.

Microbial Monitoring

According to Annex 1, microbial monitoring should be frequent, using methods like settle plates, contact plates, and active air sampling. The selection of monitoring methods, sampling sites, and frequency should be justified based on a risk assessment.

Non-viable Particulate Monitoring

Annex 1 also emphasizes real-time, continuous monitoring of non-viable particulates. This includes particles of 0.5 μm and 5.0 μm. Continuous monitoring helps in detecting events that could potentially increase contamination risk and aids in taking immediate corrective measures.

Monitoring Frequency and Locations

Annex 1 states that the frequency and locations of monitoring should be determined based on a risk assessment. Critical areas should be monitored during each manufacturing shift. The monitoring frequency should be enough to detect variations and trends in the environmental quality and should reflect the actual conditions during production.

Implementing Annex 1 Clean Room Monitoring Guidelines

In light of PIC/S GMP Annex 1 changes due on the 25 August 2023, organizations should consider the following while implementing cleanroom monitoring:

  1. Risk-Based Approach: Organizations should perform a risk assessment to determine monitoring methods, sites, and frequency. The risk assessment should consider factors such as operations conducted, the flow of personnel and materials, air flow, equipment design, and previous contamination records.
  2. Selection of Suitable Equipment: The equipment chosen for monitoring should be suitable for the intended use and should be capable of detecting the size and volume of airborne non-viable particulates as well as viable particulates.
  3. Trend Analysis: Regular trend analysis should be performed on the collected data to understand the state of control in the cleanroom. It can help identify potential contamination risks before they lead to significant problems.
  4. Training: Personnel should be adequately trained in the correct use of monitoring equipment and in the actions to be taken when excursion events occur.


Cleanroom monitoring is crucial for maintaining an optimal environment for sterile product manufacturing. Adherence to PIC/S GMP version 17 – Annex 1 guidelines can significantly reduce contamination risks, ensuring that your products meet the highest safety and quality standards. Read more about PIC/S GMP Version 17.

Complying with these guidelines may seem overwhelming, but with the right partner, it doesn’t have to be. Contact PharmOut’s GMP consultants today to help you navigate cleanroom monitoring as per Annex 1 with ease.