How often should dust collector filters be changed?

Go by the pressure gauge, not the calendar. Dust load, pulse settings and humidity set the interval, so there is no fixed schedule. Change cartridges when pulse cleaning no longer brings the differential pressure back down, or it climbs past the collector's rated range. Torn media, a failed gasket or dust downstream of the filters means replace now.

What does it mean when pulse cleaning stops bringing the pressure down?

The media is blinded, and the cartridges are due for a change. If the pressure also climbs past the collector's rated range, or dust shows downstream, change them now.

Can filters be washed and reused?

Aluminum mesh pre-filters can: wash gently, let them drain and reinstall, and replace them when the mesh is torn or crushed or no longer comes clean. A spare lets you swap in a clean one while the dirty one is washed. Among our bag filters, the Airflow Systems 7FB8-5012 is a shaker bag; the other bags are replaced, not cleaned.

Why change the pre-filter first?

The pre-filter catches larger particles and debris ahead of the main filter, so changing it on schedule is the easiest way to extend the main filter's life. The main filter in turn protects any HEPA, DOP or adsorber filter behind it.

When should a HEPA filter be replaced?

Change the pre-filters and main filters first. Replace the HEPA when its gauge still reads at the change point, or airflow stays low, after the filters ahead of it have been changed. Handle it by the frame only.

When to Change Dust Collector and Air Cleaner Filters

The signs that a cartridge, bag, box, mist, HEPA, DOP or pre-filter is due, and the order to change filters in on a staged unit.Updated November 14, 2026

Go by the gauge, not the calendar

There is no fixed schedule for changing industrial air filters: dust load, pulse settings and humidity set the interval. What tells you it is time:

Pressure drop. The differential pressure gauge reaches the unit's change point or climbs past its rated range. On a pulse-cleaned collector, the warning comes earlier: pulse cleaning no longer brings the pressure back down after a cycle, which means the media is blinded.
Airflow. Suction at the hood falls off, or the unit moves less air than it did.
Discharge. Dust downstream of the filters, or mist or smoke at a mist collector's outlet, means replace now.
Damage. Torn media, a failed gasket, or a crushed or bent filter means replace now, whatever the gauge says.

Signs by filter type

Filter	Change it when	Notes
Cartridge filters	Pulse cleaning no longer brings the pressure drop back down, or it climbs past the collector's rated range	Torn media, a failed gasket or dust downstream means replace now
Bag filters	Pressure drop climbs past the unit's rated range, or airflow at the hood falls off	Replaced, not cleaned, except the 53971 shaker bag
Box filters	The gauge reaches the change point or airflow drops; on mist units, also when mist or smoke shows at the discharge	Seat the new filter so the frame seals all around
Mist filters	The gauge reaches the change point or no longer comes down, airflow drops, or mist shows at the outlet	Keep the aluminum mesh pre-filter ahead of them clean
HEPA filters	The gauge still reads at the change point, or airflow stays low, after the filters ahead of it have been changed	Handle it by the frame only
DOP filters	The gauge reaches the change point or airflow drops	Changing the pre-filters and main filters on time protects it
Pleated filters (pre-filters)	It is visibly loaded, the gauge rises or airflow drops	The easiest way to extend the life of the main filters behind it
Poly filters (pre-filter media)	The pad is loaded	Media on a roll (50882) lets you cut a fresh pad whenever you need one
Mesh filters	The mesh is torn or crushed, or no longer comes clean	Washable: wash gently and let it drain before reinstalling
Impinger filters	The blades are bent or crushed, or the frame is out of shape	Install it in the same orientation as the one you take out
VIBRA-PULSE tube assembly	The latex is cracked, hardened or leaking	One per cartridge filter on the Airflow Systems units that use it

Change filters in the right order

Air cleaners and mist collectors often filter in stages: a pre-filter, then the main filter, and on some units a HEPA, DOP or adsorber filter after that. On the Airflow Systems Model 1200, for example, the 7FP9-0312 box filter sits behind a 2 in. polyester pre-filter and a 2 in. aluminum mesh pre-filter.

Pre-filters first. Changing (or washing) the pre-filter on schedule is the easiest way to extend the life of the main filter behind it.
Main filters next. A main filter changed on time protects the HEPA, DOP or adsorber filter behind it.
The HEPA or DOP last. Change the filters ahead of it first; replace it only if the gauge still reads at the change point, or airflow stays low, after they have been changed.

Changing cartridges

Change the full set when pulse cleaning no longer brings the pressure drop back down or airflow drops. Where the maker lists a count, the listing shows it: the Donaldson Torit T-2000, for example, takes four P031575-size cartridges.
Match the end style and seat it evenly. Seat the open end against the tube sheet and secure the cartridge with the unit's retaining hardware, so the gaskets compress evenly.
Let mist cartridges drain before you remove them, as with the Dryflo MMA cartridge (50564).
Service the cleaning system at the same time on Airflow Systems units with VIBRA-PULSE cleaning: the tube assembly (51533) is one per cartridge filter.

Need the part number for your unit? Search it at the top of the page, look it up in the filter cross reference, or browse by equipment. You can also send the make and model through the chat button, and we confirm the match before you order.

Frequently asked questions

How often should dust collector filters be changed?: Go by the pressure gauge, not the calendar. Dust load, pulse settings and humidity set the interval, so there is no fixed schedule. Change cartridges when pulse cleaning no longer brings the differential pressure back down, or it climbs past the collector's rated range. Torn media, a failed gasket or dust downstream of the filters means replace now.
What does it mean when pulse cleaning stops bringing the pressure down?: The media is blinded, and the cartridges are due for a change. If the pressure also climbs past the collector's rated range, or dust shows downstream, change them now.
Can filters be washed and reused?: Aluminum mesh pre-filters can: wash gently, let them drain and reinstall, and replace them when the mesh is torn or crushed or no longer comes clean. A spare lets you swap in a clean one while the dirty one is washed. Among our bag filters, the Airflow Systems 7FB8-5012 is a shaker bag; the other bags are replaced, not cleaned.
Why change the pre-filter first?: The pre-filter catches larger particles and debris ahead of the main filter, so changing it on schedule is the easiest way to extend the main filter's life. The main filter in turn protects any HEPA, DOP or adsorber filter behind it.
When should a HEPA filter be replaced?: Change the pre-filters and main filters first. Replace the HEPA when its gauge still reads at the change point, or airflow stays low, after the filters ahead of it have been changed. Handle it by the frame only.