There are many types of mask available that will offer different levels of protection. Whilst the choice of facemask rests ultimately with you as employer, based on the results of your risk assessment, as a general guide, fluid repellent surgical masks will suffice as a barrier to large projected droplets that are regarded as the main route of transmission of influenza virus. They are also a practical and pragmatic measure for workers not normally used to wearing a mask whilst at work.
For high risk situations, where exposure to aerosols is considered significant, FFP3 masks are recommended, in particular for healthcare workers engaged in medical procedures generating aerosols of influenza flu virus that carry greater risks of infection. Specific infection control guidance for healthcare is available on the DH website.
Surgical masks are plain masks that cover the nose and mouth and are held in place by straps around the head. In healthcare settings, they are normally worn during medical procedures to protect not only the patient but also the healthcare worker from the transfer of microorganisms, body fluids and particulate matter generated from any splash and splatter. Whilst they will provide a physical barrier to large projected droplets, they do not provide full respiratory protection against smaller suspended droplets and aerosols. That is, they are not regarded as personal protective equipment (PPE) under the European Directive 89/686/EEC (PPE Regulation 2002 SI 2002 No. 1144).
A filtering facepiece (FFP3) device is a mask which is certified to the PPE Directive. It provides a high level of filtering capability and face fit. It can be supplied with an exhale valve so that it can be worn comfortably over a fairly long period of time. It will provide an effective barrier to both droplets and fine aerosols and is the type recommended particularly for people in the healthcare sector dealing with symptomatic patients undergoing treatment where aerosols are likely to be generated.
There are also filtering facepieces FFP1 and FFP2 available but these provide less respiratory protection than a properly fitting FFP3 device.
For surgical masks, the main requirement is that people should ensure that these fit as well as possible onto the face especially around the nose and mouth particularly taking account of the manufacturer's instructions.
FFP3 masks should be fitted with care to ensure that they fit as well as possible onto the face especially around the nose and mouth particularly taking account of the manufacturer's instructions. HSE guidance recommends that these masks are fit tested, to ensure that they fit the wearer. It may be advisable to have more than one make of mask available as some masks may provide a better fit for some people than others.
Masks should only be worn once. The frequency with which they are changed will depend on the nature of the duties being undertaken as well as taking account of the manufacturer's instructions. In the healthcare setting, the replacement of masks will be governed by the requirements of infection control procedures.
Workers should adopt good working practices and not rely solely on surgical facemasks or personal protective equipment as a means of protection. They need to adopt sensible hygiene measures by washing their hands thoroughly and more frequently than normal and avoiding unnecessary hand to mouth or hand to eye contact.
If a worker is working in an area where they are separated from other people by barriers such as glass screens etc, then this will act as a physical barrier to influenza transmission. For example, workers who deal with the public from behind glass screens (e.g. in a Post Office) could not be regarded as being likely to be sneezed or coughed upon by a member of the public, even if they were to have symptoms.
General advice on assessing and controlling the risks from infection at work as well as guidance on other protective measures can be found at: