A bottle of water and a handheld fan are regularly deployed to keep cool while out and about in hot weather. With temperatures reaching record levels for June, though, a new heatwave accessory has emerged: the sunbrella.

On high streets around the country, people wielding umbrellas to shield themselves from the sun have become a common sight. On Thursday, as the Austrian Grand Prix declared a heat hazard, Lewis Hamilton was spotted in the paddock holding a Ferrari red umbrella that matched his race suit. And they’re popping up on catwalks, too. At the Dior show during Paris fashion week on Wednesday, guests including the actors James Marsden and Mike Faist were handed large cream umbrellas to help ease their discomfort as temperatures hit 38C.

Earlier in the week, at the Thom Browne show in Milan, models held grey-and-white-striped golf-style umbrellas on the alfresco runway, while the accessory on the sun-soaked front row was a black brolly. Brands including Burberry and Hermès champion three-figure brollies for downpours, an accessory now shifting from a winter to summer must-have.

“An umbrella provides your with your own personal shade,” says Brian Diffey of the University of Newcastle. Diffey’s expertise is in dermatological sciences, and he invented the UVA star rating for sunscreen in 1992. “The main benefit of an umbrella,” he tells me, “is that it acts as a heat reducer.”

Morgan Cros, founder of the London brolly brand Original Duckhead, known for its signature duck-shaped handles, describes umbrellas as becoming “much more of a year-round product”. Sales at the brand are now “steadier through the summer than they used to be”, which Cros credits to sun rather than rain.

Phil Naisbitt, store manager at James Smith & Sons, an umbrella shop in central London that dates to 1830, reports a spike in demand for its frilly sun umbrellas, particularly to use at weddings this week. “We first sold them in Victorian times, but then they went out of fashion,” he says. Now heatwaves have led to a resurgence.

Anti-UV umbrellas are also becoming more common. “UV protection is becoming a much bigger part of how people choose an umbrella,” says Cros of Original Duckhead. For its part, the New Zealand-based company Blunt designed a “UV Metro” brolly in a range of colours, including “lawn green” that it says blocks at least 99% of harmful ultraviolet rays, yours for £85. The Australian brand Solbari, meanwhile, specialises in UV protective clothing and has a £49 “sunscreen umbrella” that features an ultra-reflective silver canopy and opaque underside to help block out UV rays, and Uniqlo recently released a compact UV version for £19.90.

Diffey says a specialist umbrella isn’t necessary: they all offer a similar level of UV protection. “On a sunny day about 50% of the ultraviolet reaching our skin is coming from the sun and the other 50% is coming from the sky with UV rays hitting skin from other directions,” he explains. “A brand might say it has a UV protection of 50, but what you are actually getting is equivalent to putting on a sunscreen with a factor 3.”

However, the amount of heat protection umbrellas offer does vary. He advises looking for one with a tight weave, which will reduce the amount of light – and therefore heat – from passing through, just as it does with water droplets. A £10 umbrella and a £100 one with similar weaves will do the same. The colour is also irrelevant, he says: “Black doesn’t absorb any more light than any other colour.”

Diffey also suggests holding an umbrella as close to your head as is comfortable. “It will help shield you from direct sunlight, but remember there is still a lot of UV hitting your skin. The main advantage is that it keeps you a little bit cooler.”

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