With recent temperatures in the UK exceeding 30°C, residents are being urged to follow the 'shadow rule' to minimize the risk of sunburn. This guideline, advocated by Cancer Research UK, suggests that when your shadow is shorter than you, UV rays are at their strongest, typically between 11am and 3pm. Sunburn can occur from mid-March to mid-October, highlighting the importance of sun protection even during cooler or cloudy days. The charity emphasizes that excessive UV radiation is the leading cause of skin cancer, with up to 90% of melanoma cases potentially preventable through safe sun practices. Recommendations include wearing protective clothing, seeking shade, and using a high-factor sunscreen (at least SPF 30). During the recent heatwave, there was a notable increase in visits to NHS web pages concerning sunburn and heatstroke, indicating a heightened public interest in sun safety.