we have been completely renovating our house (and now finished [grin[ ) so my ds's are used to having tools around and know they are completely out of bounds. if we have someone in doing the work, i ensure breakfast is out of the way, boys ready and out of the way before work starts, and they are not allowed to be in the area of work at all, they may ask to look but i accompany them.
when the hallways were being decorated and it would have been impossible not to be in the way i took the ds's out for the days the men were in. nightmare for me in terms of giving them a cooked dinner each evening!
i accept a chop saws etc need to be turned off at source but as for leaving tools around, they can't be putting tools back in the van/out of reach inbetween uses etc, windows and doors need to be open. anyone who suggests otherwise obviously hasn't a clue about this sort of work! if you need to get someone in then you have to accept it's not your home for that time, it's a work site. (end of day it's different regarding not leaving anything dangerous lying about without agreement)
i would suggest this OP is about lack of common sense/understanding on the parent's part. i can understand why it is so frustrating for your DP.
i understand the difficulties if you have a child with SN but i still think you have a responsibility to occupy the child to allow a workman to get on with it and if you are mid job you camn;t just down tools and work round one person when there are other jobs to go to (and i would rather have a workman that overruns than cuts corners)
i know that some trades people aren't worthy of that title but the ones that are have difficult and demanding jobs.