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in case you're wondering how much hand sanitizer you need...

two medical students have developed a calculator that figures out how much you need and how long what you have will last.

by nicholas sokic

jun 25 2020

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2 minute read

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in case you're wondering how much hand sanitizer you need...

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even though regions across the country are now reopening in iterations, there are still protective measures in place because, well, the virus is still here. for the average citizen, it will pay to be prepared if you decide to go out for your long-awaited haircut, some groceries or anything else.

to help with that, university of guelph environmental sciences master’s graduate jasmine mah and medical student Łucja zaborowska developed a hand sanitizer calculator that you can use to determine how much of it you should buy based on your needs.

the calculator can be used to either determine how much you need or how long what you have will last. the factors to input are the amount of people it’s for, the time, the time spent outdoors (whether you’re self-isolating or going outside every day), your usage and your bottle size.

a recent cdc study showed that most people aren’t using hand sanitizer properly, or that they’re using too much or too little to be effective.

if everybody can buy what they need and understand what they need, they’ll feel more comfortable and also not buy ten bottles and then nobody has enough,” says mah. the rationing aspect also applies to the environmental impact that excess purchases would have.

before you take a swig, make sure it's not hand sanitizer

health canada warns that hand sanitizer may be packaged in beer or water bottles.

hand sanitizer is being packaged in bottles normally used for alcohol. stock/getty

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the cdc recommends using hand sanitizer with at least 60 per cent alcohol.

the lowest volume of hand sanitizer in the calculator, 59 ml, would be good for the equivalent of using sanitizer before and after meals, as well as possible after you go out. the largest size, two litres, if used in the extreme, would be applied every seven minutes for eight hours a day.

“most people would be good with using the small amount but if you’re in a business and you have a lot of interactions you’re better off using the extreme,” says mah. “if you have access to foam sanitizers it’s easier to ration because it feels like you’re using more but you’re using less, since foam adds air to it. like foam soap, it lasts longer.”

as for how to use it properly, they recommend using at least 3 ml, or over half of a teaspoon. then you rub your hands together for at least 30 seconds and let them dry on their own.

mah and zaborowska also include instructions on how to make your own sanitizer using aloe gel, isopropyl alcohol as well as tea, oregano or lavender oil.

you can also copy the html code to use the calculator on your own website.

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