I have escorted the network rail asbestos inspector around the depot on a yearly basis helping him gain access to every room/hatch/orifice to enable checks on known asbestos throughout the depot. Network rail have a report and map of all asbestos after a very thorough survey of the whole depot a number of years ago.
His job is to make sure it's all still as it was and hasn't been disturbed or has begun to degrade. The most recent inspection showed some soffit had begun to flake, it was removed within a day.
He wasn't worried about standing near it even with some flakes in the air after a poke with his poky stick. His attitude was very much it will take a lot more than a flake or two to cause problems. It is/was the endless regular inhalation deep into the lungs from working with asbestos that causes asbestosis. He was very down to earth, the first time we met I found out he'd worked with asbestos since I was 6, I'm pushing the big 4 oh now. His advice to me was worry about it in a confined space that you can't get out of, otherwise don't worry about it if you see signs warning of it...