NEWS | March 30, 2020

M113-Series FOV: CBRN Filter Replacement


Maintaining your M113-series FOV personnel carrier’s CBRN system is vital. Without it, your vehicle is non-mission capable. And you and your fellow Soldiers will be at risk!

Remember that the M12A1 filter must be swapped out prior to deployment. That’s especially important for vehicles coming out of storage and those going to an area where a CBRN threat is possible. Once a filter is installed, the service life begins immediately and can’t be extended.
Wartime Filter Exchange

Filter changes during combat operations are driven by two considerations: the amount of chemical agent the filter has been exposed to and the time the filter has been exposed to the atmosphere. In a contaminated environment, filters are only good for 48-72 hours.   
Peacetime Filter Exchange

Commanders and CBRN personnel must monitor the replacement schedules for CBRN equipment requiring filters. Change the filters whenever any of the following conditions apply:

         ● Filters are physically damaged.  
         ● Filters are waterlogged or wet.
         ● Airflow is restricted.
         ● Higher headquarters direct exchanging filters.
Temperature and Humidity

The climate will also affect the service life of filters. Use the following temperature and humidity ranges to determine how long you can expect a filter to last in different climates:

         ● 52 weeks in a cold and humid climate (less than 15°F and less than 90 percent humidity)
         ● 39 weeks in a warm and moderate climate (less than 80°F and less than 70 percent humidity)
         ● 26 weeks in a hot and dry climate (less than 98°F and less than 27 percent humidity)
         ● 4 weeks in a hot and humid climate (less than 96°F and less than 76 percent humidity).

Here’s a list of replacement CBRN parts for M113-series FOV:
NSN Item
4240-01-365-0981 Gas filter
4240-00-368-6291 Particulate filter
4240-00-018-3079 Manifold assembly
4240-00-807-6858 Precleaner and housing assembly
5340-00-763-2465 Airflow control cap
4240-00-806-0022 Spring clip
Replace filters following the instructions in your vehicle’s TM and ATP 3-11.32, Multi-service Tactics, Techniques and Procedures for Chemical, Biological, Radiological and Nuclear Passive Defense (May 16).

Download a copy of ATP 3-11.32 at: