I purchased a ProVap 110 toward the end of the season last year, and I must say, I love it! It took me about an hour to administer the first round to about 45 colonies, including the time it took to wheel the generator around through the woods. I'm glad I suited up completely beforehand, judging by the cloud of bees bouncing off my veil in an attempt to sacrifice themselves for the greater good of the colony. Once I figured out a good rhythm, I was able to move from colony to colony, keeping the temperature right close to the preset 230C. I found that if I waited just a few seconds too long, the temperature would rise to as much as 260C, and I would have to wait about a minute before I could vape the next hive.
I have a Honeywell/North 7600 series full-face respirator with a brand new pair of 7581P100L cartridges. They have a particulate filter in front of an organic vapor filter, but when I used the respirator this morning, I could still occasionally smell a slight odor from the oxalic acid, and slightly feel the irritating effects of it as well. I made sure to stay upwind of it as much as possible, and would stop breathing when I could see it drift toward my face.
The respirator itself fits me properly, and all of the sealing surfaces are in great condition. The lens is undamaged as well. I have used it in a paint booth plenty of times, and feel quite confident that I can obtain a good seal with it. The only thing I can think of which might interfere with a good seal is this 5-day stubble on my face. I'll be sure to shave before the next round and see if that makes a difference.
Is there a better filter cartridge I should be using, or is this typical of what I should expect when I get a face full of OA vapors?