UK Sun Safety Advice Highlights 11am‑3pm UV Rule

Cancer Research UK has promoted its "shadow rule" for protecting skin from ultraviolet (UV) radiation. The charity advises people to check their shadow – if it is shorter than their own, UV levels are at their peak, usually between 11 a.m. and 3 p.m. in the United Kingdom. It recommends staying in shade during that period, covering up with clothing, a wide‑brimmed hat and UV‑protective sunglasses, and applying sunscreen with at least SPF 30 generously and repeatedly.

The UK Health Security Agency (UKHSA) issued a matching reminder, urging families to avoid direct sunlight between 11 a.m. and 3 p.m., keep hydrated, and monitor heat‑related health alerts. Its guidance also includes staying cool indoors, planning outdoor activities for cooler times of day, supervising children near water, and being prepared for heat‑exhaustion symptoms. Both bodies stress the importance of re‑applying sunscreen after swimming or sweating.