Originally Posted by
unterhausen
a mask good enough for rattlecan paint jobs is not that expensive. 3m sells a really nice mask with many options for filtering. They will work for catalyzed urethane for a while. The fact that they fail silently after some period of use is problematic.
You want a mask that will take filters for VOC, they have activated charcoal
There should be a colour/life indicator somewhere on the cartridge that changes colour with exposure to the chemicals you are trying to filter out. It's kind of like reading litmus paper, so you can choose how far along the filtration cycle is good for you. I usually toss mine at about the 75% used mark.
https://www.3m.com/3M/en_US/worker-h...por-cartridge/