leave the asbestos well alone, unless its the modern asbestos replacement,which name has just escaped me
One of the most popular and first asbestos replacement products was called "Supalux" It can be identified by having a slight sparkle to it.
Unless you are certain something is not asbestos (documental proof) then it’s often best to leave well alone if you are unsure.
Even asbestos cement board which was commonly used as fascia needs to be treated properly and if removing it this should be done by licensed contractors.
Cleaning it can release fibres into the atmosphere and also contaminate the ground and drains in the water runoff. When this dries it will become dust and cause a hazard.
The simplest way to deal with asbestos cement board is to encapsulate it. i.e. paint, however it first needs to be clean, so there lies the dilemma.
If the customer is unsure what he has or what to do with it I would suggest calling in an analyst to have it checked.
I had 12 years in the asbestos removal industry and have come across just about every form of the stuff, i have also seen what happens if its not treated properly.
Oh...the fines for misuse are very large so tread carefully.