wino I am not familiar with the NZ H&S or Employment Law but all I can say is I cannot see any way sexwork could be permitted under the UK HSE.
Condoms do not protect against all infections (i.e. Herpes) and the risk of a hazard, such as a split or loose condom, vaginal/anal trauma, an aggressive or non-compliant customer would be far too high to be permissible.
I do plenty of risk assessments in my job and I promise one to one intimate contact with an unknown person, sharing bodily fluids, potentially rough physical contact, risk of emotional trauma, night work, minimum hygiene/PPE etc. would not be allowed. The high risks (possibly assessed using past studies you, yourself have presented) are too high.
Plus, if you watched the documentary you would see the prostitutes were discussing the high number of men who sneakily remove condoms without the womens' knowledge or consent. How can you protect them.
You are living in cloud cuckoo land if you think that having a driver or calling a friend to tell them their whereabouts will protect you if, for instance, a client is being slightly too vigorous, hurting you, you ask him to be gentler, he ignores you. That's just one scenario discussed by the women on the documentary: those that actually know- I trust them over you.
You are as deluded naive as the people (like my lovely, daft H, who wouldn't dream of buying a woman) who think it's just like Pretty Women and the women don't even kiss the punters! Get real, it's shit, as the documentary this thread is about, showed!