3M PAPR HEPA Longevity?

[Andrew McMorris]

I have been using a 3M PAPR mask to avoid breathing in MDF and Plywood dust. I bought a used one off of ebay and it works great.

My main question for other wearers of the mask is : how long does your HEPA filter last?

I have been wearing my mask for three months now and mostly using the same HEPA Filter daily. I test it using the floating ping pong ball device and it still gets great readings. I am surprised that it has lasted this long. Am I missing something here?

I also wear a Formaldehyde/ HEPA filter if I need to rip a several sheets of plywood or MDF. I have tested the shop with a formaldehyde tester and detected negligible formaldehyde levels.

Does anyone think that I am being overly cautious with the Formaldehyde/ HEPA filters? My workshop is a very small scale cabinet making / furniture operation. I am not manufacturing carpets or manufacturing MDF. I am just simply cutting it up. Don't you think a HEPA filter will keep out any bad MDF dust or otherwise from entering my lungs? Is the Formaldehyde filter really necessary?

Any thoughts would be appreciated.

[James Baker SD]

I cannot answer the question about formaldehyde, but I am also surprised how long my original HEPA particle filter has continued to pass the ping-pong ball test and I use the mask several times a week (active hobbyist). I am trusting the ball test as I have nothing else to go on, but my filter is well over 1 year old. Maybe my cyclone is just doing its job very well?

James

[Kyle Iwamoto]

I am not a Doctor or filter expert, but several auto painter friends have told me that when you can start to smell the fumes, time to change the filters. If you cannot smell what you are cutting, you should be fine, as the cartridges are working. The smallest particles to get through would be the aromatics, (Formaldehyde). And that is what you need to stop.