It's to do with what you're using and why you're using it, which is why schools and colleges are generally advised by CLEAPSS (with HSE input via them) rather than through the industry standards. The UK legal system with regards to H&S is risk based rather than hazard based, meaning if it doesn't lead to accidents, you can do it, whereas industry and government generally are hazard averse in order to save money from potential litigation. If we could get a few spare techs to cartwheel down the stairs carrying a few toxic things and then sue, then there might be a tightening of rules and regulations, but I wouldn't advise it... I also know OfSTED do occasionally do H&S sweeps and shut down a few colleges here and there as a result.Schools seem oddly "special" with regards to H&S otherwise I wouldn't be allowed to carry trays of chemicals up/down flights of stairs. In industry you can't carry a hot drink on stairs! 39 more get ups.
In terms of water loss though, that's a little different, it is a direct breach of regs.