SPF
Học thuậtThân thiện
Definition
- Noun:
- Sun Protection Factor: A numerical rating that indicates the degree to which a sunscreen product protects the skin from the sun's ultraviolet B (UVB) rays, which are the primary cause of sunburn. A higher SPF number indicates a greater level of protection.
Usage
- SPF is used to describe and compare the effectiveness of sunscreen lotions, creams, sprays, and other sun-protective products.
- It is typically followed by a number (e.g., SPF 15, SPF 30, SPF 50).
- It is a standard measurement in dermatology and consumer health.
Examples
- Noun:
- For daily use, a moisturizer with SPF 30 is recommended.
- This sunscreen has a very high SPF of 50+.
- What is the SPF of that beach sunscreen?
Advanced Usage
- "Broad-spectrum SPF": Refers to a sunscreen that protects against both UVB rays (measured by the SPF number) and UVA rays (which cause aging and long-term damage). The SPF number itself only quantifies UVB protection.
- Look for a broad-spectrum SPF to ensure complete protection.
Variants and Related Words
- Sunscreen (n): A lotion, cream, or spray that protects the skin from the sun, typically characterized by its SPF.
- Sunblock (n): A term sometimes used interchangeably with sunscreen, though it traditionally referred to products that physically block rays.
- UPF (Ultraviolet Protection Factor) (n): A similar rating system used for fabrics and clothing, indicating how much UV radiation is blocked.
Synonyms
- Sun protection factor: The full form of the acronym.
- Protection factor: A more general term.
Notes on Meaning
- SPF is a measure of , not duration. It indicates how much longer you can stay in the sun without burning compared to unprotected skin. For example, SPF 30 means it would take 30 times longer to burn than with no protection, assuming proper application.
- It is a crucial concept for skin health and cancer prevention.
Noun
- the degree to which a sunscreen protects the skin from the direct rays of the sun