TheBrownNote
Good thing I wore my brown pants
This chart, created by the Army is to be used for work/rest times as well as hydration charts per hour, based upon work load.
Notice the work rest time ratios.
These are highly trained, apparently highly in shape, professional soldiers.
I would consider our work to be Moderate to Heavy work depending on route, etc.
This should be the standard for healthy heat related working conditions.