Ultraviolet (UV) rays are electromagnetic radiation from the sun, with wavelengths shorter than visible light but longer than X-rays.
Types of UV rays:
- UVA (320-400 nm): Penetrates deep into skin, causing aging and wrinkles.
- UVB (290-320 nm): Primarily responsible for sunburn and skin cancer.
- UVC (100-290 nm): Absorbed by Earth’s atmosphere, not reaching the surface.
Effects of UV rays:
- Skin damage and cancer
- Premature aging
- Eye damage (cataracts, macular degeneration)
- Immune system suppression
- DNA damage
Protection from UV rays:
- Wear protective clothing and hats
- Apply broad-spectrum sunscreen (SPF 30+)
- Seek shade, especially during peak hours (10am-4pm)
- Wear UV-blocking sunglasses
- Avoid tanning beds
UV rays also have beneficial effects:
- Vitamin D production in skin
- Disinfection and sterilization
- Medical treatments (phototherapy)