If it’s 100 degrees out, does your boss have to give you a break? Probably not.

Just watch the reports it's happening across the USA in different states. This is why I'm a huge supporter of make sure to take care of your health because your employer can replace you.

https://www.fox13news.com/news/desantis-signs-bill-banning-florida-counties-from-requiring-heat-and-water-breaks-for-outdoor-workers

https://kypolicy.org/house-bill-500-takes-away-kentucky-workers-lunch-and-rest-breaks-and-cuts-their-pay/

In my young adulthood I dug ditches and framed houses for 8 hours per day in 110 degree heat. We got 3 breaks the entire day, two 10 minute breaks and one 30 minute lunch. It was... unpleasant.

Land of the free

He doesn't have to, but he probably should, if he wants future value from you as a non-dead worker.