NASHVILLE, Tenn. (AP) — State labor officials, warning about the danger of heat stress, say it's crucial for employers to allow their employees to be able to drink water often and allow them rest in the shade. John Winkler, administrator of the Tennessee Occupational Safety and Health Administration, said summer can be very dangerous for outdoor workers. Signs of heat stress are headache, dizziness, fainting, weakness, wet skin, irritability, thirst, nausea or vomiting.