> one of the chemicals we filled up with from large canisters (for C-46? E-46?) had a warning label it would react with ordinary house-hold cleaner chems and f

> one of the chemicals we filled up with from large canisters (for C-46? E-46?) had a warning label it would react with ordinary house-hold cleaner chems and form mustard gas Presumably you're referring to the bleach stage (or blix stage which is bleach + fix). I'm pretty sure regular bleach is more common in households than C-41 bleach. Edit: Bleach + ammonia makes mustard gas, and ammonia is contained by some window cleaners. I think it's a lot more common for someone to mix bleach and window cleaner (thinking it works better) than to mix window cleaner with photographic chemicals.