We used to have sector wide unions. So even if you were employed by a small business with a few employees, you were still covered by a larger union.

I have family members who really appreciated the neck mounted fans that blow up at back of neck. relatively cheap at like 20-35.

Might be worth getting a giant insulated water bottle to fill with ice, or bringing your own mini fridge and plugging it in somewhere. You could also try getting a Dr note saying you need accommodation - supply of ice water or cooling vests.