EN ISO 22612
EN ISO 22612 addresses particle-borne microbial transfer, where micro-organisms adhere to dust or skin scales and pass through the material without liquid.
Test principle: talc powder is loaded with spores of Bacillus atrophaeus and applied to the specimen. Defined vibration simulates movement and agitation in wear. Culture media beneath the specimen capture penetrating particles, and the number of colony-forming units is evaluated.
Significance: the method is relevant for clean air suits and operating theatre clothing, where the wearer's skin scales are the principal source of micro-organisms. It complements the wet test under EN ISO 22610.
Application: a test basis in EN 13795 for clean air suits and part of the test framework of EN 14126 for protective clothing against infective agents.
Frequently asked questions
Why does EN ISO 22612 test in the dry state?
Because micro-organisms are also transferred without liquid, bound to dust particles or skin scales. For clean air suits in particular this transfer route is decisive, so wet testing alone is insufficient.
Which test organism is used?
Usually spores of Bacillus atrophaeus. Spores are robust, readily standardised and reliably countable on culture media, which secures the reproducibility of the method.
Where is EN ISO 22612 particularly relevant?
For clean air suits and operating theatre clothing. There the wearer's skin scales are the principal source of micro-organisms, so the dry particle barrier determines effectiveness.