If you only look at the filter material of the HEPA composition filter, then regardless of whether the filter material used in the HEPA composition filter is glass fiber, PP fiber, PP&PET composite fiber, melt-blown polyester non-woven fabric or melt-blown long fiber, its rated service life is all for 8-12 months.

　　There are dust particles with a large star diameter greater than 0.3μ floating in the air. If only HEP eight high-efficiency filters are used in the clean workshop, it is easy to appear full of dust in a short period of time.

　　In order to prolong the service life of the HEPA composition filter, the clean workshop with higher air quality requirements usually adopts a three-stage air filtration system, and a medium-efficiency filter capable of filtering dust above 1m is set before the HEPA high-efficiency filter. A primary filter capable of dust of 5μ or more is installed before the filter.

　　After two layers of primary and medium-efficiency filters, when the air flows to the HEP eight high-efficiency filter, only morning floats with a diameter of less than 1 are left, which can reduce the purification pressure of the HEPA composition filter and prolong the service life.