ISO 16604
ISO 16604 supplements the purely visual test of ISO 16603 with microbiological evidence.
Test organism: the bacteriophage Phi-X174 has a diameter of around 27 nanometres, making it smaller than virtually all human pathogenic viruses including HBV, HCV and HIV. A material passing this barrier will also retain larger pathogens.
Procedure: the material is exposed to a phage suspension at the pressure determined under ISO 16603. The reverse side is then examined for penetrated phages, evaluated by culture on a host bacterial strain. The result is reported as pass or fail.
Context: for protective clothing a pass leads to marking with the suffix B under EN 14126. For protective gloves the same methodology is used in EN ISO 374-5 and entitles the product to the pictogram with the word VIRUS.
Frequently asked questions
Why is the bacteriophage Phi-X174 used?
At around 27 nanometres it is smaller than virtually all human pathogenic viruses, harmless to humans and readily detectable by culture. A material passing this barrier also retains larger pathogens such as HBV, HCV or HIV.
What is the relationship to EN ISO 374-5?
EN ISO 374-5 applies the same test methodology to protective gloves. A pass there entitles the product to the pictogram with the word VIRUS; for protective clothing it yields the type suffix B under EN 14126.