Information Bite No 208 Wearing Masks During the COVID 19 Pandemic

Members of the public could be putting themselves more at risk from contracting coronavirus by wearing face masks, one of England’s most senior doctors has warned.

Jenny Harries, deputy chief medical officer, said the masks could “actually trap the virus” and cause the person wearing it to breathe it in.

“For the average member of the public walking down a street, it is not a good idea” to wear a face mask in the hope of preventing infection, she added.

The World Health Organisation (WHO) states:

Only wear a mask if you are ill with COVID-19 symptoms (especially coughing) or looking after someone who may have COVID-19 (Doctors, Nurses, Carers, etc.).

If you are not ill or looking after someone who is ill then you are wasting a mask. There is a world-wide shortage of masks, so WHO urges people to use masks wisely.

The most effective ways to protect yourself and others against COVID-19 are to;

  • frequently clean your hands for at least 20 second each time,
  • cover your cough with the bend of elbow or tissue, and
  • maintain a distance of at least 2 metres.

Types of mask:

A surgical mask is a disposable medical device that protects against infectious agents transmitted by “droplets.” These droplets can be droplets of saliva or secretions from the upper respiratory tract when the wearer exhales.

A surgical mask does not protect against “airborne” infectious agents so it will not prevent the wearer from being potentially contaminated by a virus such as the coronavirus.

 Respirators have three classes of disposable particulate respirators (FFP1, FFP2 and FFP3).

  • FFP1refers to the least filtering of the three masks. This mask is mainly used as a dust mask (home renovations and various types of work).
  • FFP2masks are mainly used in construction, agriculture, and by healthcare professionals against influenza viruses.
  • FFP3masks are the most filtering mask of the FFPs. They protect against very fine particles such as asbestos.

The effective use of respirators requires the wearer to be face fit tested for each make and model of mask to be worn and be clean shaven every day.

HSE guidance (HSG 53) recommends that masks are worn for less than one hour at a time after which the wearer should remove it and take a break.

Full face visors can also be used. These do not require face fit testing and the operatives will not need to be clean shaven. One potential problem with visors is that they can steam up on the inside. This can be alleviated by using air-fed visors.

If this kind of protection is to be used, consideration of the compatibility with other items of PPE (e.g. safety helmets, ear defenders, safety glasses, etc.) must be taken into account.