Does anyone have any words of wisdom to guide me easily through the mire of heat stress calculation, WBGT, ET etc etc. In short I'm looking at a situation where we need to work in a live boiler room and I'm hearing that the wet bulb temperature has been measured at 37C and dry 43C. Alarm bells are ringing for me, but HSE's website info isn't all that helpful and I’m looking for guidance on a suitable and simple work regime to cover this sort of work.

That was the easy bit redken. Based on the available data our boiler house WBGT is off the scale @ 39 relative to the guidance table @ 22/23 for the anticipated work rate, hence the alarm bells! I haven't been able to track down any info that correlates these sort of figures to a sensible work regime. Clearly, we are going to have regular breaks, staff rotation and lots of water etc, but what should this look like - 15mins/hr? Any comments much appreciated.