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SUN BURN/ SUN TAN AND SPF




Sun burn is a form of radiation which affect living tissues that results from over exposure of ultraviolet radiation. Eg: sun 

Common symptoms: reddish skin, hot to touch, pain, mild dizziness. 

Suntan: Exposure of skin to lesser amount of UV radiation. 

UV-B is band which causes sunburn. It also initiates the production of melanin in the skin. UV-B also have minor effect on skin damage and penetrate deeper into the skin. 

The intensity of UV-A radiation is more constant than UV-B without variations during the day throughout the year. 

Both UV-A and UV-B can cause skin damage and wrinkles, collagen breakdown, formation of free radicals. 


Sun protection factor (SPF): 

A sunscreen’s efficacy has been measured by it’s sun protection factor (SPF). The sun protection factor (SPF). The sun protection factor is a measure of the effectiveness of a sunscreen product. In simple terms, the SPF of a product is the number of times longer a person can stay exposed to the sun without getting sunburn when exposed to the sun without getting sunburn when using the product. SPF is not an amount of sun protection factor per second. It indicates how long it will take for UV-B rays to redden skin when using sunscreen, without the product. For instance, someone using a sunscreen. An SPF-15 sunscreen screens 93% of sun’s UV-B rays. SPF-30 protects against 97% and SPF-50 protects against 98%.

Article By: Nisha Joshi (Nepal)
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