Copper "touchless" door opening hooks (or keys) appear all over the internet with a simple pitch: use them instead of your fingers to open doors and punch keys to protect yourself from germs. Brass is an alloy of copper and mostly zinc, and copper has antimicrobial properties. So, will it protect you from germs and, most importantly, COVID-1
Copper has microbial properties
The first thing to know is that copper really has antimicrobial properties. That's why you'll find brass used on common contact items such as doorknobs and pressure plates. But it is not instant germination; it can take up to two hours for copper to kill a wide variety of harmful microbes.
We have known about the antimicrobial properties of copper for centuries and the EPA has thoroughly tested it on various viruses and bacteria types, including E. coli, Staphylococcus aureus (MRSA), Influenza A virus and even fungi. Depending on the purity of the copper, the results were quite excellent, with a kill ratio of 99.99% within 2 hours.
We have not tested it against SARS-CoV-2
However, this does not mean copper kills any type of bacteria and virus. The number of germs we tested is much smaller than the strains of viruses, bacteria and fungi that exist in the real world.
We have not tested it thoroughly against SARS-CoV-2, the virus that causes COVID- 19. Without those tests, we cannot be sure that it works completely against SARS-CoV-2, and we may not. Even the Copper Development Association, a non-profit organization tasked with ensuring the proper public claims of copper, says the same in an official statement on its site. Officially, the EPA only allows claims against six types of bacteria (not viruses).
In early tests, some studies have shown that copper can be effective against SARS-CoV-2 within 4 hours, which is double the time of other bacteria and viruses we tested. But we will need even more tests to know for sure.
Copper does not prevent cross-contamination and must be cleaned
In every statement about the antimicrobial properties of copper, you will find two details that are very important for copper hooks. Dirty copper does not kill micro-organisms as effectively and copper does not prevent cross-contamination. Here is the version from the Copper Development Association:
Laboratory tests show that, when cleaned regularly, surfaces of uncoated copper alloys kill> 99.9% of the following bacteria within 2 hours of exposure: MRSA, VRE, Staphylococcus aureus , Enterobacter aerogenes, Pseudomonas aeruginosa and E. coli O157: H7. Copper surfaces are complementary and not a substitute for standard infection control practices and have been shown to reduce microbial contamination, but do not necessarily prevent cross contamination or infection; users should continue to follow all current infection control practices.
Note the sections "regular cleaning" and "not necessarily preventing cross-contamination" in the statement.
You will see that marketing is referred to in almost every brass key if you look closely. Usually the terminology is something that corresponds to "with regular cleaning and proper treatment". Without cleaning, copper becomes less effective at killing microbes. Or rather, a barrier of dirt and grime forms that prevents the copper from killing bacteria.
So, the more often you touch your brass or brass key without cleaning it, the worse it gets for the person you want it for — kill germs. And since it can take hours for copper to do its job, if you use a hook to open a door, slide it into your pocket and then push your hand into your pocket to get it out again – you've got the point probably completely defeated. Copper can deposit germs before it kills them.
That is why most copper hook manufacturers display the devices hanging from a belt loop or key fob. But even that is not a perfect solution; you must be diligent not to touch the part of the hook that touched a door or PIN, or brush your hand against the part of your pants that contacts your copper hook.
How do you clean copper? That depends on what made it dirty and how hygienic you want to make the hook. But according to the Copper Alloy Stewardship "standard hospital cleaners are compatible with antimicrobial copper materials …" but you should be careful not to use anything that doesn't leave the surface "waxed, painted, varnished, varnished or otherwise coated. & # 39; That goes back to disrupting the interaction between copper and germs.
And of course, if the brass hook you buy turns out to be brass, you risk damaging the brass while cleaning it, destroying the chance of germs.
So, what should you do?
You might be wondering if copper hooks are not the magic bullet to protect yourself from germs what can you do? Well, unfortunately there is no unique magic bullet. The EPA has a list of disinfectants that are effective against SARS-CoV-2, but you will likely find them in a limited supply. solid.
As the CDC suggests, it is best to wash your hands thoroughly and do not touch your face and nose when you are in public. Wearing a mask can not only protect you from infection, but it can also help not touch your face. After all, it is a physical barrier.
Even if you use a tool like a brass hook, you still need to wash your hands early and often. Did you hold the brass hook to open a door? Wash your hands anyway. And in particular, you should do this for at least 20 seconds with hot water and soap.
If you want the perfect version of hand washing, you can go beyond singing a happy birthday twice and following the World Health Organization (WHO) protocol. Google will help you if you ask.
And of course, in addition to good hygiene, self-isolation is a good defense against infection. The more people you meet, the greater the risk of exposure. Conversely, avoiding people also avoids the risk of exposure. And if you're still not sure, check out reputable sites like the CDC and NIH for more information.
But in the end, $ 20 spent on soap and warm water is a safer bet to protect you from infection than a brass hook filled with faint but just within the confines of legal promises.