The investigation into the safety of kids’ Halloween costumes comes three years after Claudia Winkleman’s daughter, Matilda, went up “like a fireball” while trick or treating.

The Government launched a nationwide investigation into fire safety of children’s fancy dress after the Strictly Come Dancing host launched a campaign on BBC’s Watchdog programme urging manufacturers to take action.

Sainsbury’s increased its fire safety standards for Halloween costumes to meet the same strict standard that applies to nightwear.

Asda and Tesco also pledged more rigorous testing after Matilda’s £5 supermarket-bought witch costume went up in flames.

Children’s Halloween and fancy dress costumes for sale across the UK are now subject to spot-checks by watchdog Trading Standards.

Andre Turner, Community Safety officer at Essex County Fire and Rescue Service, said: “It doesn’t take long for these Halloween costumes to stick to your skin after setting alight.

“Our advice is to stop, drop and roll immediately.

“That helps to put the flame out and reduce injury as well.

“The best advice is to buy costumes which are fire retardant because they are the safest ones.

“If you’re going to make your own don’t make them with flammable materials.

“As a parent, don’t use tealights in pumpkins – use a battery operated light where there is no heat source.”

A quirk in EU safety regulations means children’s costumes are classed as toys, rather than clothing.

This means they are not subject to the same strict flammability standards that regular nightwear is.

But now flammability measures have been adopted by thousands of retailers after concerns over how quickly a costume can take to ignite.

These robust rules now guarantee costumes will have a maximum burn rate of 10mm per minute, rather than the previous 30mm per minute standard, making them safer.

The measures have been introduced as part of a voluntary code of practice for members of the British Retail Consortium.