BEM 4GP Gas Mask test

Testing the Belgian BEM 4GP Gas Mask/Respirator. The BEM 4GP was briefly adopted in the 90s by the Belgian army to replace the old M51 masks, however, within a few years they replaced it with Avon FM12s, rumors that the masks leaked was often cited but I have found no evidence.
The mask here is tested with an old filter against aerosols to see if the mask still keeps an airtight seal. The mask has a unique filter intake that can be twisted into three positions.
The mask takes standard NATO 40mm STANAG filters.