Which type of UV radiation is primarily responsible for causing sunburn?

UVB radiation is primarily responsible for causing sunburn. This type of ultraviolet light has a shorter wavelength and is more energetic than UVA rays, making it the main contributor to the burning effect on the skin when exposed to sunlight. UVB rays can penetrate the outer layer of the skin and directly damage the DNA in skin cells, leading to inflammation, redness, and ultimately sunburn.

In contrast, UVA radiation, while it can penetrate deeper into the skin and contribute to photoaging and skin cancer over time, is not the primary cause of immediate sunburn sensations. UVC radiation is mostly absorbed by the Earth’s atmosphere and does not typically reach the ground in significant amounts, and UVD is not a recognized type of ultraviolet radiation in the context of skincare or sun exposure. Understanding the distinction between these types of UV radiation is crucial for effective sun protection and skincare practices.