中英对照：鉴别优质口罩的几个步骤

 
几周前我写了一篇介绍各种口罩的文章后，一些朋友要求我帮助他们选择合适的口罩。有关不同口罩的文章，请点击：http://chinesenewsgroup.com/news/668597

Ever since I wrote an article a few weeks ago talking about the different kinds of facial masks, I was asked by friends to help them to select the right kind of masks for them. For that article on the introduction to masks, please click: http://chinesenewsgroup.com/news/668597

今年3月，加拿大进口了大量的中国口罩。这些口罩不是用于一线卫生工作者的那些有质量要求的口罩。实际上，它们是加拿大首席公共卫生官谭咏诗所说的“非医用”口罩。

There is quite an inventory of facial masks that arrived in March from China. These are not the type of masks that would meet the quality requirement of Health Services procuring such for front line Health workers. In fact, they are “non-medical” masks mentioned by the top Canadian Health Official Teresa Tam.

今天你也许关心的话题：

庚子赔款与世纪之战
新冠状病毒与种族歧视
疫情之下非洲要求中国减免巨额债务

想要阅读与本文有关的话题？请点击本文末的链接！



作为一个非谋利组织成员，我要为团队成员买适合日常使用的口罩。在退休之前，我干了超过40年的质量控制工作，我的工作经验成为了这项任务的宝贵资产。接到任务后，我立即寻找鉴别口罩质量的测试和检查方法。下面是我的心得体会。
 
As part of a team to locate masks for members in our organization, I got involved in the hunt for suitable masks for daily use. After spending more than four decades working in the Quality Control field before retirement, my experiences become a valuable asset in this exercise. I immediately look for testing and inspection methods that I can use in this quest. Let me share my experiences with you below.

买口罩时，让消费者困惑的第一件事可能就是口罩包装。这些包装盒上通常标有不同的国际医疗质量标志。仅要了解这些标志是否重要就足以让人头疼。

The very first thing that would confuse any mask purchasers will be the packaging boxes. Different international medical, quality standards and their logos are commonly labelled on the boxes. One would need to do researches just to understand the significance or insignificance of these items.



许多口罩包装都附有ISO和FDA的注册证书。所有这些注册都没有任何意义！你根本无法知道这些口罩生产商究竟有没有注册。此外，这些证书几乎都是假的。ISO和FDA的网站有识别这些证书的介绍，但你会发现这些证书与你买的口罩生产商没有关系，甚至与口罩生产商不在同一国家/地区。
 
Many packages are supplied with registration certificates for ISO and FDA. All of these registrations mean nothing! The marking on the masks packaged in the box cannot be identified with the registrations in all cases. Further more, almost all of the certificates turn out to be fraudulent documents. The registrars' web sites will identify these certificates belonging to factories at other addresses or even outside of the manufacturer's country.

这些口罩的生产商也会声称自己的产品符合ASTM标准（（编辑注：ASTM是美国材料测试协会，American Society of Testing and Materials的缩写。）。他们会在包装盒上印上“高级过滤”，“无玻璃纤维”和“外科一次性使用”之类的话，但你不必对他们当真。
 
The boxes can also be identified themselves as meeting ASTM Level(s). They will use words like “High Filter Efficiency”, “Fibreglass Free”, and “surgical disposable” but again these claims can be ascertained and must be ignored.

医用口罩有三层材料。外层和衬里是无纺布，中间层是熔喷布。熔喷布是口罩最重要的部分。熔喷布是由微纤维和纳米纤维制成的，这种材料可以让气体从聚合物熔体中的细孔穿过，而随机沉淀在熔喷布的纤维起到防水作用。熔喷布可以阻止微生物进入或离开。带有皱纹的口罩是让你可以增加口罩从鼻子到下巴的覆盖面。口罩通过耳环，头带或松紧带固定在头部。
 
Medical masks are constructed as a three-ply device. The out layer and backing layer are non-woven  fabric while the middle layer is a Meltblown material serving as the most important barrier. Meltblown sheet is fabricated out of micro- and nanofibers where a polymer melt is extruded through small nozzles surrounded by high speed blowing gas. The randomly deposited fibers form a sheet of waterproof product. The meltblown material acts as the filter that stops microbes from entering or exiting the mask. Pleats are commonly used to allow the user to expand the mask such that it covers the area from the nose to the chin. The masks are secured to the head with ear loops, head ties, or elastic straps.



检查口罩质量的第一步是看它是否防水。将口罩折叠成杯状，向里倒水时不会漏水。接下来，将口罩从中间剪开，看看口罩有没有3层，且中间一层是熔喷布。虽然我检查的口罩都有三层，但有人告诉我他们买到过只有两层的口罩！
 
The first thing to do is to test out if the mask is waterproof. When water is poured on the inside with the mask forming the shape of a cup, it should hold water without leakage. Next, I would cut open the mask at the middle point across the length of it to verify that it is 3 layered and contains the Meltblown sheet in the middle. Even though I have not seem this, I hear about masks with two layers only!

下一步是对熔喷布进行“撕裂测试”。用手慢慢将熔喷布撕开时你会感到阻力，并且在撕裂的边缘可以看到丝质材料。把熔喷布对着光线时应该看不到任何细孔。用打火机或火柴点燃熔喷布的边缘时，它不会燃烧。
 
After this, I would do a “tear test” on the Meltblown layer. Tearing it apart with my hands slowly, I should feel resistance and a silk-like texture can be seen at the tearing edges. Holding this sheet up against a light, there should be no detectable holes when examined with the naked eye. When the edge of the Meltblown layer ise burned with a lighter or match, it would distinguish by itself.



熔喷布也应携带静电。一种方法是用擦手纸与熔喷布合在一起，看看他们能否吸住。检查口罩外层和内层表面上的孔，孔越小，产品越好。为了对我购买的口罩质量有信心，我都按以上步骤检查和测试。
 
The Meltblown layer should also carry static electricity. One method is to put small cut-up pieces of facial tissues against it and the two surfaces would come together. Inspecting the holes on the surface of the outer and inner layers would give an idea of effectiveness of the mask on a relative basis – the smaller the holes, the better the product. I have done all of these inspections and tests to provide a level of confidence for the purchasing of the masks.

我还听说过有人使用小型激光笔测试熔喷布。显然，激光不应穿透熔喷布。如果是这样，过滤95％以上（BFE> 95％）细菌的能力将令人怀疑。我自己没有尝试过这种方法。这种方法只是最近由香港的一位化学教授提出的。

I also hear about the use of a small laser pointer to fire at the Meltblown material. Apparently, the light should not penetrate the material and come out “clean and clear” on the other side. If it does, then the ability to filter out 95 plus percentage (BFE > 95%) of the bacteria will be questionable. I have not tried this method myself as this was only recently demonstrated by a Chemistry Professor out of Hong Kong.



总之，不要相信口罩盒子上的标签和证书，因为它们很容易调包。批量购买口罩时，不要相信你拿到的“样品”，他们很容易在送货时以假充真。由于你我没有实验室设备，以上的测试和检查只能基本防止你被骗。

To summary my experiences – Do not believe in box labelling and certificates as they can repackage masks into any box anytime. Do not believe in the “sample” you are given when buy in bulk. Chances are, you will fall into the “Bait and Switch” scheme. Testing and Inspections are very rudimentary when executed without the proper equipment in a laboratory and they only provide approximate results on a relative basis.

买到有质量的口罩并非易事。希望这篇文章对你购买口罩有所帮助。

The road to buying good facial masks is a treacherous one. I hope I have helped to navigate you to your destination without detours.