Guidelines on the Use of Facemasks

• Wearing a facemask is just ONE of the ways to prevent the spread of respiratory tract infections. Observe good personal hygiene is utmost important.

• People with respiratory symptoms should wear a facemask to reduce the chance of spread of infection. Carers, and those visiting sick people, should also wear a facemask.

Even if you do wear a facemask, you should continue to maintain a high standard of personal hygiene because no mask can offer total protection.

Guidelines for Staff and Students

During the Non-SARS Period

To reduce the chance of transmitting infection, individuals listed below are recommended to wear masks:

• Medical staff, students and those working in the clinical environment
• People who have fever, cough, a cold or flu like symptoms
• People who care for those with fever, cough, a cold or flu like symptoms
• Catering staff
• Cleaning staff

When SARS is Reported Overseas

Additional to the above measures, a mask is recommended for:

• Outbound travellers visiting SARS affected areas
• As per instructions given by hospital/clinics for staff, patients and visitors

When SARS is Reported Locally

A mask is further recommended for:

• People visiting crowded or poorly ventilated places
• People who have been in close contact with SARS patients should wear a mask for 10 days from the last contact. Social contacts of a SARS patients may also wear a mask.

Please be reminded to exercise judgment in accordance with guidance as above. In general, anyone who feels the need to wear a mask is advised to do so.

How to Wear a Mask

1. Wash hands before wearing a facemask
2. Follow the instructions on the packet carefully, if available.
3. In general, when wearing a surgical facemask, the following should be noted:
   • The facemask should fit snugly over the face.
   • The coloured side of the facemask should face outside, with metallic strip uppermost.
   • Tie all the strings that keep the facemask in place or fix the rubber bands of the facemask round the ears properly.
   • The facemask should fully cover the nose, mouth as well as the chin.
   • The metallic wire part of the facemask should be fixed securely over the bridge of the nose to prevent leakage.
   • Once in position, do not fiddle with your mask as you could transfer any contamination from your hands to your face.
   • Under general circumstances, the surgical mask should be changed daily.
4. Put the facemask into a plastic bag and tie it properly before putting into rubbish bin. The bin should be covered with a lid.
5. Replace the facemask immediately if it is damaged, wet or soiled.

Types of Masks

a) Surgical Masks appear to offer a barrier for the wearer against liquid droplets resulting from a cough or sneeze and they can act as a reminder to the wearer not to touch their nose and mouth.

Note: smaller and lighter droplets can easily be drawn in through any gaps between the mask and face.

b) Filtering Facemasks (N95) or equivalent are designed to protect the wearer from inhaling airborne particles.

They should be worn by medical staff and carers dealing with patients suffering from SARS. There will be resistance to breathing when the mask is properly worn.

c) Other types of masks are available and their effectiveness can be highly variable. Masks with just one band are unlikely to provide a decent face seal.

Note: The effectiveness of any mask is highly dependant on the filtering material from which the mask is made. The wearer should take great care to fit the mask properly, to prevent gaps appearing between the mask and the nose, cheeks and chin.

HKU Task Force on SARS

August 10, 2004