They produce redness, tenderness, pain, swelling and slight fever. 2nd-degree burns affect deeper skin layers. Symptoms are more severe and include blisters. 3rd-degree burns involve all skin layers. Tissue injury caused by chemicals or radiation, including sunlight.
Lightning strikes can cause internal burns with minimal external signs.
Occupations involving exposure to heat or radiation, such as firefighting, police work or defense-factory work. Hot water heaters set too high. Fireproof your home. Install smoke alarms, plan emergency exits and have regular fire drills. Wear protective gear and observe safety precautions around heat or radiation.