This is a major event in the world of ultra-clean environments. For the first time in fifteen years, the revision of ISO 14644-1 has significantly changed the rules for cleanroom classification. Published at the end of February, this new standard revises the allowable particle concentration limits in the air and fundamentally changes the practical and technical requirements for classification. From designers to auditors, all stakeholders in the industry are affected, regardless of their field of activity.
One month after the publication of the standard, the magazine La Salle Propre decided to give the floor to those who would have to implement these new rules in the field. Until then, few cleanroom managers had examined the subject in depth, with most waiting for the final version to be published. The pharmaceutical industry was the first to react, undoubtedly because of the regulatory nature of classification in this industry, but also because of certain unavoidable deadlines, such as summer maintenance shutdowns.
On March 22, the magazine, in partnership with Aspect, therefore invited three representatives from the pharmaceutical industry and two testing and inspection companies to a round table discussion. The discussions began with a shared observation: both users and service providers generally viewed the changes introduced by the 2016 standard positively. “Our feeling is that this new version is moving in the right direction and can only improve the situation,” said Alain Varilh, Technical Manager for Healthcare Professions at Groupe Mape. Overall, professionals considered the requirements of the revised standard to be simpler and more consistent.
Among the improvements highlighted were the introduction of a single rule for processing results regardless of the room area, as well as the possibility of determining the compliance of a sampling location without waiting for subsequent statistical calculations to be validated. Participants also welcomed the removal of the 95% Upper Confidence Limit (UCL). Compliance with a cleanliness class now consists of obtaining a result at each sampling location below the maximum allowable concentration, without requiring uniformity from one location to another.
What changes in 5 points:
- Removal of the class limits for airborne particle concentrations.
- Modification of the minimum number of air sampling locations. The calculation formula has been replaced by the application of a table (Table A.1 in the standard’s annex) for cleanrooms with an area of up to 1,000 m². For areas above 1,000 m², the number of locations is determined using a formula: A = 27 × A / 1000.
- The principle of dividing the room into a grid is maintained, with the room divided into sections of approximately equal area, the number of sections corresponding to the number of sampling locations. The new requirement concerns the selection of the sampling location, which must be representative of the characteristics of each section.
- New rules for determining compliance or non-compliance with an airborne particulate cleanliness class, including the removal of the statistical calculation of the 95% Upper Confidence Limit. The new rule is straightforward: a cleanroom is considered compliant when every sampling location tested is compliant. The standard also allows additional sampling locations to be added depending on the activity carried out.
- The frequency for requalification of airborne particulate classification is explicitly specified: once per year.