Ok, it looks like the product below — while quite handy for sanding and other particulate-matter-heavy environments — wouldn’t have helped us much with the BMW. So what should we have used to get those two years back?
The National Ag Safety Database (NASD) has a lot to say on the subject. They recommend using a respirator with the appropriate chemical type insert for the particular fumes you’re looking to avoid. (While units like the one in the post below simply remove particles from the air by pulling them through a filter, fumes must be removed by chemical reaction. Thus, the proper insert will contain chemicals that will react with the one(s) you’re looking to trap, holding them in the cartridge.)
The NASD also recommends a supplied air respirator. 3M makes a truly incredible selection of these, as linked below. They offer 23 different “headtops” (applications ranging from hoods, visors, and welding visors to helmets) along with multiple lines of supplied-air (and powered-air) systems. In some configurations, these provide fresh air from a remote source, avoiding entirely the need for a filter.
Cost? It varies widely based on what you select. However, an air compressor filtration system, hoses, and headtop can be had for well under $1k, and if 3M makes the appropriate chemical filter for your application — they make many — a powered-air system with headtop can be had for less than $500.
Enjoy that extra two years — we plan on spending them drooling and bitching about the government.