lessingham, I have a 25 year history of blowing asbestos brake dust into the air, sometimes to the point of the asbestos dust being so thick it looked like the car was on fire. One place where I worked, we ground brake shoes to fit the brake drum. Yes, the ground off asbestoes went into the air and some went into a collection bag mounted on the brake shoe grinder.
I worked in another shop with 8 other guys that occasionally did blew brake dust into the open air. Replacing or working on a Clutch (vehicle with a manual shift transmission) wasn't as prone to be that dusty but we also blew out clutch dust with an air nozzle.
One thing I have discovered is some people are more susceptible to cancer caused by asbestos and people I know that smoked and were exposed to asbestos seem to have had a much higher rate of cancer.
I didn't smoke and had 2 lung CT cancer screenings, both showed no signs of cancer.
I have read and looked up many, many articles related to asbestos and cancer. Some doctors knew asbestos was linked to cancer in the late 1800. Some insurance companies knew lung cancer was caused by asbestos in the early 1900. This is about when asbestos manufactures got asbestos caused lung cancer classified similar to an industrial accident and not a hazardous substance.
For an eye opening view about how asbestos was miss handled, watch a couple of videos related to Cassiar Alberta Canada Asbestos. Or watch one of several other videos related to Vermiculite Insulation.