ITK Envifront has several norms for classifying filter materials:
We have since 1988 been involved in the aftermarket for fabric filters, we have thus accumulated much experience within the field of the filtration process. This experience lead to the development of an in-house unique filter media classification method. As a customer to ITK Envifront you can gain better performance on your fabric filter installations, lower the emissions, withhold higher capacity or simply increase the bag life time. Our classification method is founded on three EFN standards (Envifront standards).