Four of these answer "what is the number": heat index, wet bulb, WBGT and the printable chart. The other four answer "so what do I do": work and rest minutes, a running pace, an acclimatisation schedule, and whether to walk the dog. Where a value is modelled rather than measured — every WBGT on this site, and every pavement temperature — the page says so on the value itself rather than in a footnote.