What does SPF stand for in the context of sun protection?

SPF stands for Sun Protection Factor, which is a measure used to indicate the level of protection that a sunscreen provides against UVB rays, the type of radiation primarily responsible for sunburn and contributing to skin cancer. The SPF number indicates how long a person can stay in the sun without getting sunburned compared to not wearing any sunscreen at all. For example, if a person would burn after 10 minutes of sun exposure without sunscreen, using an SPF 30 sunscreen theoretically allows them to stay in the sun for 30 times longer (approximately 300 minutes) without burning, assuming proper and generous application.

This understanding is critical when selecting and applying sunscreen, as it helps individuals make informed choices about their sun protection strategies. The other terms presented do not accurately represent the standard terminology used in the dermatological and cosmetic community for sun protection guidelines.