The New EN 17141:2020

The purpose of the standard is to guide users in achieving and demonstrating microbiological control. To this end, the normative section adopts the Quality Risk Management (QRM) approach of EU GMP Annex 1, which is currently under consultation. Because current methods allow biocontamination to be measured only indirectly, EN 17141 deals only with monitoring, not with classification.

These measurements are made using growth-based methods, which causes a delay between taking a sample and getting a result. In addition, since not all viable microbes can be grown through incubation, measurement sensitivity is not very high.

According to the working groups, most of ISO 14698 is still appropriate. However, it was decided to remove unnecessary sections (or sections already covered in other standards). Although the standard deals with microorganisms rather than viruses, endotoxins, prions or pollen, the term 'biocontamination control' was retained for the sake of continuity.

Table 1 compares the topics covered in ISO 14698 Parts 1 and 2 with those in EN 17141.

One challenge is that different fields of application have different requirements for biocontamination control. For example, microbial steps may be part of a production process in the food industry, whereas in aseptic manufacturing the complete absence of microorganisms is an important quality attribute. In addition, the new standard must not conflict with existing industry-specific regulations.

Great emphasis has been placed on microbiological surface and air sampling methods and their validation. For example, the d50 (a) value has been introduced as a parameter for the physical collection efficiency of air samplers, so that different active air samplers with the same d50 value can be compared.

a. Physical collection efficiency: the threshold value defining the aerodynamic equivalent particle diameter at which the sampler collects 50% of airborne particles (d50 value)