<P> Minor sunburns typically cause nothing more than slight redness and tenderness to the affected areas . In more serious cases, blistering can occur . Extreme sunburns can be painful to the point of debilitation and may require hospital care . </P> <P> Sunburn can occur in less than 15 minutes, and in seconds when exposed to non-shielded welding arcs or other sources of intense ultraviolet light . Nevertheless, the inflicted harm is often not immediately obvious . </P> <P> After the exposure, skin may turn red in as little as 30 minutes but most often takes 2 to 6 hours . Pain is usually most extreme 6 to 48 hours after exposure . The burn continues to develop for 1 to 3 days, occasionally followed by peeling skin in 3 to 8 days . Some peeling and itching may continue for several weeks . </P> <P> Ultraviolet radiation causes sunburns and increases the risk of three types of skin cancer: melanoma, basal - cell carcinoma and squamous - cell carcinoma . Of greatest concern is that the melanoma risk increases in a dose - dependent manner with the number of a person's lifetime cumulative episodes of sunburn . </P>

How long until a sunburn starts to peel