View Single Post
Old 01-24-2021, 11:22 AM
1001001's Avatar
1001001 1001001 is offline
Join Date: Dec 2014
Location: Just Minutes from KBVI!
Posts: 1,128

I work for a company that makes activated carbon (not charcoal--the difference in terms is important!) that goes in many different kinds of gas masks and respirators. We don't make the respirators ourselves, but manufacture the main ingredients that get the job done.

No one respirator is going to have a good fit for every user--people's face shapes and bone structures are just too different. If the 3M can't be made to fit you, there are others you can try, as you mention--Honeywell, MSA, and others. Unfortunately you kind of have to try several if you have a face shape that is not "standard."

You probably already know, but I'll point out here that if you have facial hair (even light stubble), a respirator that might normally seal well for you when you are clean shaven will no longer provide adequate protection. And a marginal seal on smooth skin will become useless with facial hair. When I go to prime parts, I make sure I have at least run the beard trimmer over the seal area--I have a respirator that seals pretty well and I can get away with a little stubble, but others cannot.

Between uses, you can store the respirator or just the cartridges in a sealed zip-lock bag--this will protect the activated carbon from adsorbing any other volatiles that may be in the air where you store it. Over time, if the activated carbon is not stored sealed, the adsorption pore sites will be used up and the overall effectiveness reduced or exhausted.

I have a set of 3M VOC cartridges that have lasted me at least 4 priming sessions of about an hour each--your mileage will vary depending on how well ventilated your paint space is and how well you keep them sealed between uses. I wear a forced air hood over my respirator, so I probably get more life out of mine than if I were simply relying on the carbon to remove VOCs in the direct painting environment.

Once you have a well-fitting facepiece, as soon as you can detect any trace of VOC aroma when you breathe in, it is time to change the cartridges--the bed depth in these cartridges is rather thin and at the earliest signs of breakthrough you are being exposed to the hazard.

I would not recommend sealing one cartridge off out of two--that will only cause the single cartridge to become exhausted more quickly, and it becomes harder to breathe. Far better to seal the whole respirator in a bag when done with it.

Prior to bagging the respirator after use, use isopropyl alcohol to clean the facepiece, otherwise bacteria from your face and mold may tend to grow on the rubber. Also, skin oils can have a detrimental effect on the rubber, so cleaning it before storage is important.
Reply With Quote