It's not exactly my forte, but I'll give you some info on how we handle this type of activity.

When we needed to (lead work is the biggie), we did the following:

Until historical information was established, we suited up all of our workers (full clothing and breathing apparatus) that had to go into an environment containing lead.

The various activites were broken down: welding, grinding, labor inside, (but not in extremely close proximity to airborne dust creating activities). Personnel conducting each activity wore a monitor capable of sampling airborne particulate. Data was gathered and based on that information, PPE guidelines were established.

From the nature of your question, it seems like you need real data, as opposed to MSDS information. I believe you would need to establish a set of baseline data based on the typical activities that you perform, that cause fumes. That data would be based on monitoring air at a distance that approximates how close your workers are to the actual smoke plume.

Just my opinion.

Charles

I agree with Charles,
Air Quality Sampling is relatively cheap and can be done over an eight hour period to get the data needed to establish a baseline. Once you know what the levels are, you will be better prepared to know how to handle them. Not knowing the exposure levels will make mandatory safety equipment necessary, when you may not need it in the first place. I ran into that here in our plant, because the dilution of fresh air into the welding bays(from overhead doors opening and closing throughout the day) created an atmostphere where no extra gear was needed to meet the exposure levels set by OSHA.
John Wright

PS: if you are monitoring welder's exposure be sure to place the filter, that is collecting the data, under the shield where the welder is actually breathing instead on on his/her clothing because it may give a false indication of what the welder is actually breathing.