Most people dont realize there way of living could be a hazard to others. I too have done installs in s**t holes. If there is truely a health hazard, then let the sub know what they have to do to correct the problem before the job can be rescheduled. There is no way, if legit, that a boss will fire you if conditions are that bad you have to walk away. If children are in the household, than a call to child welfare is not a bad idea. That said, there is absolutly no excuse for poor craftsmanship.
This is CABL.com posting #184317. Tiny Link: cabl.co/mV61