Special problems and shorter life are what different filter media are known for. The mattress depth of filters is between 10 and 18 inches. The filters run for 2 weeks or longer before being resterilized.
The bag in/bag out housings are bought by some manufacturers. The filters have a big surface space. It is necessary to provide air with a low microbiological load. High effectivity particulate air (HEPA) filters are capable of remove bigger particles than this and may even be capable of remove smaller particles than this. Retention for particles of less than zero.2 m is 99%. This type of filter is used in LAF rooms.