Temperatures are set to hit 34˚C this week and there are fears they could catch fire in the heat.
NHS staff have been told to remove all alcohol-based hand gels from their cars after a number of fires broke out.
The warm weather can cause the alcohol in the sanitiser to evaporate.
This in turn means flammable vapours are released.
The vapour can then ignite if there is a spark and start a fire inside the car.
Some have exploded
The heat can also cause pressure to build up inside the bottle and some have exploded.
A number of pictures show the after effects of bottles that have caught fire.
And they've done a lot of damage to the cars they were in.
Make sure you take your hand sanitiser out of your cars, especially in the upcoming heat!
Fire hazard 🔥
— Sara Beverley Jones (@SaraBeverley) June 23, 2020
The NHS warning revealed: "This quick share is to alert all colleagues to the potential fire risk in vehicles, caused by alcohol-based hand sanitiser."
So, it is no surprise to see pictures circulating on social media showing severely damaged vehicles due to hand sanitiser bottle that had ignited inside a vehicle sitting in direct sunlight.
It added: "We have received a number of reports of hand sanitiser being the cause of fires when left in vehicles in the hot weather the UK is currently experiencing."
Cars can reach up to 50˚c
An expert at operational health and safety training company CE Safety reiterated the advice.
The spokesperson said: "If it is 25˚C outside, the estimated vehicle interior air temperature can reach up to 50˚C if left for a couple of hours."
Temperatures are set to reach the mid-30Cs in parts of the UK today and tomorrow.
They added: "So, it is no surprise to see pictures circulating on social media showing severely damaged vehicles due to hand sanitiser bottle that had ignited inside a vehicle sitting in direct sunlight."
Millions of Brits carry hand sanitiser with them due to the pandemic.
It's an effective way to guard against coronavirus.
However, in the hot weather, it's best kept inside the home.
The safety expert did have another option though, should you want something to leave in the car.
"One alternative solution might be to use disposable gloves whilst in the car, which may remove the need for hand sanitiser. Just remember to throw them away immediately after use," they said.
ED! contacted the NHS Property Services about our story.
They told us: "At the end of May, we received notifications from safety officers at Unison. They raised media reports from US Fire Authorities that hand sanitisers were catching fire in vehicles."
It added: "As part of our COVID-19 strategic pandemic plans, NHSPS has acquired significant levels of hand sanitisers to keep our frontline engineers safe."
It continued: "We take our duty of care toward our staff very seriously. As such, our health and safety team issued an internal message to highlight the potential risks associated with hand sanitisers in vehicles. With the hot summer approaching, there was concern for our facilities management staff who would be transporting this material."
It concluded: "This decision to raise awareness across colleagues was made in good faith. It is now our understanding that the risks associated with hand sanitisers in vehicles only become apparent when in contact with a spark. We will be issuing a formal alert to clarify this situation."
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