Body & Health · Tool

How many minutes until you burn?

The midday sun in the UAE is strong for much of the year, and sunburn doesn't sting while it's happening. Guess how long your skin can take today, see the answer from the live UV index, then use the timer when you go out.

What the UV index means

The World Health Organization sorts the UV index into five bands, from low to extreme, each with its own advice.

Sunscreen, honestly

SPF is about UVB

SPF 15 filters about 93% of the UVB rays that cause sunburn, SPF 30 about 97% and SPF 50 about 98%. None blocks them all.

Most of us use too little

The label is tested with a thick layer. Aim for about 2 teaspoons for your face, neck and arms, and 2 tablespoons for your whole body in swimwear.

Reapply every 2 hours

And straight after swimming, sweating or drying off with a towel, even if the bottle says water resistant.

Shade and clothes come first

Sunscreen isn't a reason to stay out longer. Shade, loose clothes that cover you, a wide-brimmed hat and sunglasses do most of the work.

Summer midday in the UAE

Each summer, from 15 June to 15 September, UAE law stops outdoor work in direct sun from 12:30 to 15:00. That rule is mainly about heat. For sunburn, the strongest UV comes in the hours around midday all year round, so plan time outside for the early morning or late afternoon.

How it's worked out

The maths. Burning starts at one "minimal erythema dose": about 200 J/m² of sunburn-weighted UV for skin type I, 250 for II, 300 for III, 450 for IV, 600 for V and 1,000 for VI. Each point of UV index is 0.025 W/m² of that light. So at UV 10, type II skin collects 250 J/m² in 1,000 seconds: about 17 minutes. Sunscreen multiplies the time, but most people put on half the tested amount, which gives roughly the square root of the SPF. SPF 30 then works more like SPF 5 or 6.

Vitamin D. Skin makes vitamin D from the same UV that burns. For lighter skin, a few minutes of midday sun on the arms and legs is usually enough; darker skin needs several times longer. When the UV is under 3, very little is made. There's no need to burn to get it.

What's approximate. The UV comes from the Open-Meteo forecast, not a meter beside you, and clouds, dust and shade change it minute to minute. Skin types and burn doses vary a lot between people, and darker skin can still burn and still gets skin damage. Sunscreen wears off with sweat, towels and water whatever the label says. So every time here is an estimate.

If you do get burnt

Cool it down

Get out of the sun. Cool the skin with a cool shower, a bath or a damp cloth, and use an after-sun cream or aloe vera gel.

Drink water

Sunburn and heat dry you out. Sip water, and cover the burnt skin when you go outside again.

Know when to get help

See a doctor for blisters over a large area, a high temperature, chills, or feeling dizzy or sick. A very young child with sunburn should be checked. In an emergency call 998.

This is an estimate to help you learn, not medical advice. Skin reacts differently from person to person. If you take medicines that make you more sensitive to the sun, ask your pharmacist or doctor.

Sources: World Health Organization, Global Solar UV Index: A Practical Guide (2002): the five UV index bands and their advice, 1 UV index point = 0.025 W/m² of sunburn-weighted UV, and ground reflection (dry sand about 15%, grass, soil and water under 10%, fresh snow up to 80%). Fitzpatrick skin types I to VI, with typical minimal erythema doses for each type used in UV dosimetry research. Faurschou and Wulf, British Journal of Dermatology (2007): sunscreen applied thinly gives much less than the label's SPF. American Academy of Dermatology and the Skin Cancer Foundation: how much UVB each SPF filters, and reapplying every 2 hours and after swimming or sweating. NHS (UK): how much sunscreen to use and how to care for sunburn. UAE Ministry of Human Resources and Emiratisation: the summer midday work break. Live UV: Open-Meteo forecast API. Your location is used only to ask Open-Meteo for the forecast and is not saved.