Face masks: All you need to know about where, when and why you need one

Ireland is shifting from ‘should’ wear a face mask to ‘must’ wear one

Ireland got its response to Covid-19 largely right. Case figures and deaths don't lie. But we got some things wrong – notably on face masks.

In spite of remarkable progress, there are no widely available treatments and no immediate prospect of an effective vaccine. Covid-19 still poses the same risk as it did during the pandemic’s first days . The threat of a second wave lurks ever present.

That is why making the wearing of face masks compulsory is essential. Ireland is coming late to this approach after much dithering and too much confused messaging.

Where are we now on face masks?


Wearing face masks on public transport is already mandatory and is to become mandatory in indoor spaces such as shops.

We are shifting from “should” wear them to “must” wear them. And because of the extent of health threat, this goes beyond “basic good manners” or respiratory etiquette.

The hard lessons from having to implement actions in a nightmarish scenario of constantly emerging knowledge about an insidious global threat don’t need to be raked over. Scaling up effective actions knowing what we do now needs to be the focus.

Likewise, the message has to be right; browbeating people into wearing them won’t work. We may, however, be at a tipping point. This week, Taoiseach Micheál Martin was out and about wearing a face mask. Many more people have their face covered on public transport – one media report suggested nine out of 10 people on Dublin’s Luas were wearing masks.

What’s the latest evidence for wearing face masks?

There is no study of scale providing definitive proof but science is about weighing up probability and evaluating risk.

A UK study found population-wide face mask use could push transmission down to controllable levels, and prevent further Covid waves when combined with minor lockdowns.

A US study found if 80 per cent of a closed population were to don a mask, infection rates would statistically drop to approximately one-twelfth the number of infections compared to “a live-virus population” in which no one wore masks.

Emerging evidence prompted the World Health Organization to strengthen advice in their favour.

A University of Edinburgh study recently found masks can limit how far exhaled breath travels out by up to 90 per cent, while another study found the daily growth rate of infections fell by 40 per cent after mask use was made compulsory in the German city of Jena.

Many are wearing masks, so why are we seeing rising cases?

The capricious nature of Covid-19 knows no bounds. It’s clear outdoor transmission is a minimal risk, the big challenge is stopping transmission in indoor settings, where individuals are in close contact with limited ventilation for a prolonged period of time.

Compounding this, according to Prof Devi Sridhar of the University of Edinburgh, is the role presymptomatic and asymptomatic transmission can play in spreading the disease – where an infected person spreads the virus before they develop symptoms themselves, or where they never develop symptoms.

“Relying only on those with symptoms of coronavirus to self-isolate is not enough to stop transmission given the role that these silent carriers play in its spread,” she wrote in the Guardian.

Covid-19 exploits those opportunities for infection in confined spaces. Washing hands properly before and after going to such places remains a critical action – wearing face masks while in that zone of potential spread is just as important.

So what is the best advice?

Face masks do not need to be worn in the open air or while driving a car but should be worn routinely where physical distancing is not possible. A mask protects the public from the wearer who might not know they are contagious.

Medical-grade masks are the most effective barrier. Evidence on the protective value of single-use paper masks or reusable cloth coverings is less clear, but still suggests they can contribute to reducing transmission.

For those over 60, whose immune system is weakening coinciding with ageing, and those with underlying conditions, the case is clear-cut. Moreover, they should wear medical-grade masks.

What about indications of reckless socialising?

Reinforcing regulations on mandatory wearing of face masks will soon be in place. Then it’s down to enforcement; lack of implementation will quickly undermine credibility.

Such measures are justified, especially where inadequate precautions are being taken. Given clusters are increasing around the country – and in spite of much good work curtailing Covid-19 – it suggests wearing a mask has been a matter of individual choice for too long.

Is there an outstanding messaging issue?

A perception of invulnerability among young people persists. This necessitates a new approach to messaging, underpinned by great clarity. It should embrace wearing masks; handwashing and getting tested quickly if showing signs of Covid-19.

Wearing a mask is one of the most important defences in keeping Covid-19 at bay. Widespread adoption will enable further opening up of society and travel between countries with similarly low levels of infection to Ireland. That should be part of messaging too, ie the rewards.

The social norm has to be wearing a mask, while accepting some people cannot wear one. We are not there yet. It’s a small price to pay for getting closer to normality – and pushing back that second wave.

Kevin O'Sullivan

Kevin O'Sullivan

Kevin O'Sullivan is Environment and Science Editor and former editor of The Irish Times