I Category of masks for preventing novel coronavirus infection

1. Disposable surgical mask

Disposable surgical masks are made from over three layers of 28g non-woven fabric; the air-permeable masks have an environmentally friendly plastic strip at the bridge of nose, free of metal. Disposal surgical masks can help prevent respiratory infection and should be destroyed after being used once.

2. Surgical mask

Surgical masks have three layers: an outer hydrophobic layer, a middle filter layer and an inner hydrophilic layer, which is designed to be non-woven fabric for comfort. When wearing a mask, the blue waterproof side should face outwards and the side with metal strip be on top. Do not wear it the other way around. After placing ear loops around your ears, pinch the metal strip to conform to the shape of your nose and smooth the mask over your cheek to achieve close facial fit.

3. Medical protective mask (N95 / KN95 particulate respirator mask and mask of higher protective grade)

The common N95 respirators are surgical mask 1860/9132 (blue-green) that helps protect against certain airborne biological particles and 8210 dustproof mask (white). Please buy the medical protective mask resistant of biological particles, common brand of which is 3M. Compared with surgical masks, medical protective masks can provide better protection and filter over 95% of non-oil particles. Please note that N95 respirators and KN95 respirators have the same protection level, even if tested under American and Chinese standards respectively.

Cotton mask can help keep you warm but can neither block most bacteria nor prevent respiratory infection. So do the industrial masks with respiratory valve for they are used to prevent dust. It is advised to wear professional surgical masks or medical protective masks in densely populated places (hospitals, airports, railway stations, subways, buses, airplanes, trains, supermarkets, restaurants, etc.).

II. Discern qualified surgical mask

The qualified surgical mask generally has product registration number marked on its package. The numbering rule is normally as follows: the mechanical registration standard of X (X is the abbreviation of province, e.g. E for Hubei, Zhe for Zhejiang, Yue for Guangdong) + registration year + 264 (belong to No. 64 of class II medical device) + number. It can be identified through the website of National Medical Product Administration.

1. Log onto the website of National Medical Product Administration.

http://www.nmpa.gov.cn (site URL with gov represents government website).

2. Click Medical Devices Identification, select domestic device or imported device based on the origin of the mask.

3. Enter the registration number (the mechanical registration standard of X + 201XXXXXXXX).

4. Select the corresponding products based on place of origin.

5. Click in and pay attention to two parts: 1. Product name: if it reads surgical mask or medical protective mask, you can use the mask free of concern. 2. Manufacturing standard: the manufacturing standard of medical protective mask (KN95/N95) is GB19083—2010, that of surgical mask is YY0469-2011 while that of anti-smog mask is GB2626-2006. Generally, mask for industrial protection is used to prevent flying spittle.

III Discern 3M medical protective mask (N95/KN95)

1. Boxed masks

If the 3M K95/KN95 masks you buy are box-packed, you can find out whether they are real or not by search the anti-counterfeit code via the official WeChat account of 3M, Happier Life with 3M.

In addition, a clear sign is marked on the package box that can be distinguished by naked eye. For real 3M masks, you can see on the box a laser anti-counterfeiting label. The red and black parts of the label will turn into red and the white part will turn into light blue at a certain angle, while this is not the case for fake masks. Furthermore, the counterfeited ones do not have the obviously uneven "3M" printing.

2. Individually sold masks

If the 3M masks are individually sold, you can discern it through the various ways listed below.

1. Smell: real 3M masks do not have obvious smell (active carbon masks smell light active carbon). The rubber loops should have no smell.

2. Printing: the laser printing mark of real 3M masks slants 45 degrees while the ink printing of fake ones is generally uneven with white dots on the words and does not have the 45-degree slant.

3. Logo: the logos shows sharp contrast. The words of real 3M are closely spaced while that of the fake ones are loosely spaced and can be removed by hands.

4. Digital sequence: the digital sequence at the lower edge of genuine masks is obvious and the words are also arranged in stripes, while the printing of the counterfeit masks is unclear.

IV Other notes

During this period time of fighting against novel coronavirus, as masks are becoming increasingly scarce, some immoral merchants collect and refurbish used masks for sale. Faculty and students should not lose their judgement. For your own health and safety, please turn to eligible drugstore or other trustworthy channels.

The Steering Committee of Novel Coronavirus Prevention and Control of SUSTech