UV index and sunburn: what to know

The UV index describes the strength of ultraviolet radiation reaching the ground. It is a guide to how quickly unprotected skin may be injured, rather than a measure of temperature or brightness. Strong UV can pass through light cloud, reflect from sand, water, and pale surfaces, and reach exposed areas even when the air feels comfortable. Sunburn often appears as redness, warmth, tenderness, or later peeling; blisters suggest a more significant injury. Sun-damaged skin also accumulates with repeated exposure.

Move out of direct sun and cool the skin with a lukewarm shower or a clean, cool damp cloth. Apply a bland moisturiser while the skin is still slightly damp, drink fluids, and wear loose clothing. Do not pick peeling skin or break blisters. Avoid further UV exposure until the area has settled, and cover it rather than relying on sunscreen over raw or blistered skin. A pharmacist or clinician can advise whether a suitable emollient or other treatment is appropriate.

Seek medical help for extensive blistering, severe pain, marked swelling, fever, vomiting, confusion, faintness, or signs of infection such as spreading redness and pus. Urgent assessment is sensible after a large exposure in a young child, or if eye symptoms, breathing difficulty, or dehydration occur. Recurrent burns or a changing spot on sun-exposed skin also merit a dermatology review.

Ask which sunscreen texture and protection level suit your skin, whether a blistered area needs dressing, and how to protect a medication-sensitive or pigment-prone area during outdoor activities.