(HealthDay News) -- While there's no such thing as a safe sunburn or tan, some cases can damage the skin permanently.

Sunburn occurs when sunlight or another ultraviolet-light source exceeds the ability of the pigment melanin to protect the skin.

The U.S. National Library of Medicine mentions these warning signs of a serious sunburn:

• Feeling dizzy or faint.
• Rapid breathing or pulse.
• Extreme thirst, a sunken look to the eyes or not producing urine.
• Skin that feels cool or clammy, or appears pale.
• Rash, fever, chills or nausea.
• Pain in the eyes or sensitivity to light.
• Painful blisters.