Years ago in another Life we posed the same question in an Industrial Unit. "When does it become Too Hot to Work"? The answer we were given was that there is no upper limit to temperature.sirchewey wrote:RM decide to halt delivery in icy conditions due to health and safety, at what point will they consider it too hot? Is it a personal choice? Do we all have the option of saying it's too hot to deliver and due to feeling light headed and suffering from heat exhaustion we cannot continue?
Because the H&S Executive had to consider such places as Founderies (in which I've also worked) they couldn't put a Top Temperature on it! 
I don't claim to be Highly Intelligent but surely the HSE could have chosen a Maximum Temperature ... with the exclusion of Foundries and Steel Works etc....... FFS.
