EN 17141-4: Establishing Microbiological Control

This section of EN 17141 covers several important points: what your contamination control system should focus on, sources of contamination, risk assessments, and building your environmental monitoring plan. In essence, EN 17141-4 explains why a contamination control plan (or system) matters and how to implement one.

The first thing Section 4 states is that a system must be established to maintain microbiological contamination control, and that this system must be kept in place over time.

Within this system,

• Sources of microbiological contamination in the cleanroom, and the routes by which they spread, must be identifiable,
• The risks posed by these sources and routes must be assessed and then addressed.
• A schedule for the microbiological contamination monitoring system, including valid sampling methods, must be established.
• Appropriate alert and action levels must be defined, along with the measures to be taken when they are exceeded.
• It must be continuously verified that product contamination rates, monitoring results, risk assessments and control methods meet the standards and performance parameters, such as monitoring limits.
• Documentation must be created and maintained.
• Training must be provided for all personnel involved in using the cleanroom or controlled environment.

Section 4 describes the different sources of microbiological contamination, such as people, air supply, product materials, utilities and machinery. As noted above, as part of our system we must be able to identify these sources and have a plan for each risk in the event of contamination.

Finally, EN 17141-4 explains how to build an environmental monitoring plan, including monitoring locations, monitoring frequencies, alert and action limits, the documentation system and personnel training. These factors should be determined through a risk assessment that takes into account the cleanroom application and the products and materials used or developed in the cleanroom.