The risk of damage is greatest with infants and young children. 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.