The ‘candle test’ can show you if your face covering is effective - here’s how to do it at home

Monday, 27th July 2020, 3:35 pm
Updated Monday, 27th July 2020, 3:35 pm
How to test if your mask is effective (Photo: Shutterstock)

With face coverings across the UK now mandatory in more and more public spaces, making sure you’re wearing an effective face covering is imperative.

This at-home test can instantly show you if your face covering is effective, or if you need to invest in something with more protection.

What is the candle test?

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Simon Kolstoe, a senior lecturer in Evidence Based Healthcare at the University of Portsmouth, wrote about the candle test in an article for The Conversation.

To do the test at home, all you need is a lit candle and your face coverings.

Simply try to blow out the candle while wearing your face mask. Kolstoe explains that the face covering that makes it hardest to move the flame “will probably provide the best barrier for projecting the virus forward and through the face covering.”

If you’re able to blow out the flame, then your mask does not provide enough protection from spreading germs via your breath, and you should consider investing in a covering with more layers. The more layers that a face covering has, the more protection it will offer.

The World Health Organization (WHO) has advised that people should ideally use a three layer mask, as this is considered to be more effective than double or single layer masks. The UK government advice recommends at least two layers.

Bill Nye approved

American scientist Bill Nye demonstrated the candle test experiment on his TikTok account when the conversation around face masks in America was just beginning.

In the video, Nye shows himself holding an N95 face mask up against his nose and mouth, attempting to blow out a candle, with the air barely moving the flame.

He explains, “The reason we want you to wear a mask is to protect you, sure. But the main reason we want you to wear a mask is to protect me from you and the particles from inside your respiratory system from getting into my respiratory system.

“Everybody, this is a matter literally of life and death, and when I use the word literally, I mean literally - a matter of life and death. So when you’re out in public, please, wear a mask.”

Where can I get a face mask?

In Scotland and England, face masks are mandatory on public transport and in shops - in Northern Ireland, they’re currently only mandatory on public transport.

Wearing a face mask has been proven to protect people from the spread of the coronavirus, so wearing suitable face covering is important.

Many pharmacies and supermarkets are selling disposable face coverings - these must be discarded after each use and cannot be reused or washed.

There are many places online where you can purchase reusable face coverings as well, from chain online retailers like Amazon and eBay, sporting brands like Adidas and Reebok, and independent retailers on Etsy.