EE WAS JACKHAMMERING AND SHOVELING HARD BUILD UP INSIDE THE UNLOADING PIT WITH OTHER EMPLOYEES. CONDITIONS WERE HOT AND DIRTY. HE HAD HIS SHIRT SLEEVES ROLLED UP WHILE PERFORMING TASK. AFTER AWHILE, EMPLOYEE ROLLED SLEEVES DOWN AND ABOUT TWO HOURS LATER HIS INSIDE OF BOTH ARMS STARTED BURNING ON PRE-EXISTING SUNBURN.