Ultraviolet radiation like UVA and UVB has been well documented to have multiple effects on human skin. It not only causes skin cancer, but also cutaneous aging like seborrheic keratosis, photomelanosis (pigmentation on sun exposed parts), wrinkles, polymorphous light eruption, melasma, freckles, lentigines and urticaria or hives.
Sun Protection Factor:
Sun protection factor (SPF) is measured in the laboratory with a light source and it is a theoretical amount of time you can stay in the sun without getting sunburned. For example, SPF of 30 would allow you to stay in the sun 30 times longer than you could without protection. SPF refers to the degree of protection from ultraviolet B and does not provide protection against ultraviolet A.
Types of Sunscreen:
Sun Protection Measures:
Sun protection of photo exposed areas and certain measures to protect us from direct sunlight are as follows:
How to Apply a Sunscreen:
To apply a sunscreen, follow the teaspoon rule:
The sunscreens protect the skin from damage by ultraviolet rays, provided they are applied liberally 30 minutes to 1 hour before an exposure. It should be reapplied after swimming or sweating or during prolonged ultraviolet exposure. A SPF of at least 30 should be applied to the most fair skinned individual and reapplied after 4 to 6 hours as there is no such completely waterproof sunscreen. So, reapplication is important.
Daily use of sunscreen is more protective than intermittent use. Sunscreen should be applied even on cloudy days.
For further doubts regarding sun protection, consult a dermatologist online --> https://www.icliniq.com/ask-a-doctor-online/dermatologistLast reviewed at: 07.Sep.2018