School's out for summer for most British children, with many leaving the classroom under the Met Office's first-ever extreme heat warning. Not everyone has left just yet, however, as some kids could remain in the classroom until the end of the week. They may have an opportunity to get out earlier if the temperature crosses a predetermined threshold.

       The latest heatwave has broken temperature records for 2021, with temperatures pushing 32C at least twice since last week.

       Many children have had to brave the heat decked in a blazer, shirt and shorts as they wait for the end of term.

       The uniform and heat combination could prove unbearable for some, and Government guidance offers some limited protection.

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       The Health and Safety Executive (HSE), the UK's workplace health regulator, advises correct workplace and school conditions.

       HSE states there is no absolute minimum or maximum temperature enshrined in law but advises at least 13C at the least.

       The regulators add they cannot provide a "meaningful figure" for upper temperatures given the extreme heat required in some settings, such as foundries or glassworks.

       But the temperatures need to be at least "comfortable" for workers and children.

       Offices and classrooms must ensure they take measures to cool down overheating settings.

       In the workplace, this may mean turning up or installing air conditioning units.

       And in the classroom, teachers may open windows or doors to let in a summery breeze.

       They could also permit children to wear alternative uniforms or drop the blazer if need be.

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       The National Union of Teachers (NUT) previously cemented these measures in a report.

       The union explained the benchmark for introducing them is 26C maximum.

       Experts have previously argued excessive heat could leave children fatigued and dehydrated, leaving their learning abilities impaired.

       Previously, they have called for children to go home if temperatures push 30C.

       Unfortunately for impatient children, they are unlikely to get an impromptu day off.

       While the union states teachers should consider closing "unacceptably hot" classrooms, it recommends they resume lessons elsewhere rather than send children home.

       The NUT only advises they send children home if they can provide parents with "reasonable notice".

       Parents won't have an automatic right to take a day off with children sent back home during the heat.