Before we go into the details of making a hand sanitiser it is worth giving some background which will help you to make informed judgements about the making and use of sanitisers. There two distinct threats here; bacteria and viruses. Some hand sanitisers advertise a high rate of effectiveness against bacteria and may not be effective against viruses (Coronavirus).
Dr. Philip Tierno, professor of microbiology and pathology at the New York University School of Medicine is quoted as saying that if your hand sanitiser mixture is 60 per cent alcohol or higher, it will probably be effective. The effectiveness, of any alcohol component over 60 per cent or higher should kill the coronavirus.
Coronavirus has an outer shell that may make it easier to kill versus other ‘naked’ viruses. Some viruses have an envelope surrounding their protein shell. They inherit this envelope from the host cell membrane during the propagation process. Enveloped viruses are distinct from “naked” viruses, which lack this envelope. As Coronavirus is an ‘enveloped’ virus it has an outer lipid membrane layer. Basically, it’s surrounded by a fat layer. Washing your hands with soap and water has the ability to ‘dissolve’ this greasy fatty layer and kill the virus.
The new variant of the Coronavirus SARS-CoV-2 appears to be fairly easily spread. But the good news is that it’s not among the most transmissible diseases out there. Unlike some extremely contagious pathogens, the SARS-CoV-2 coronavirus is not thought to spread via smaller droplets that can remain floating in the air for long periods of time.
The new coronavirus spreads mostly through person-to-person contact within about a 6-foot (1.8 meters) radius, according to the Centers for Disease Control and Prevention (CDC). People with COVID-19, which is the disease caused by the coronavirus, spread their viral particles through coughing and sneezing. The particles can end up in the mouths or nasal cavities of those nearby.
It may also be possible to pick up Coronavirus SARS-CoV-2 by touching a surface where the virus has recently landed and then directly touching (or with an infected handkerchief) one’s mouth, nose or eyes, although this form of transmission is thought to be less common. Some coronaviruses can persist on hard and soft surfaces for days. As the current coronavirus may be a new variant not much is known about its ability to survive on surfaces. Alcohol-based solutions are known to be effective at killing those coronaviruses that remain on surfaces, including the skin.
The basic mix of sanitiser gel is:
Two-thirds cup rubbing alcohol (99% isopropyl alcohol).
One-third cup pure aloe vera gel.
This mix will give a 66% alcohol content and thus should be effective. The ingredients are combined in a mixing bowl and decanted into pump or flip lid type plastic bottles.
Ensure that the Aloe Vera used is pure and free from other ingredients such as fragrances and preservatives.
Essential oils can be used to add a fragrance and antiseptic properties to hand sanitiser, for instance: lemon, orange, and tea tree. Lemon and orange are both natural disinfectants with a pleasant fragrance. Tea tree oil has been proven to kill viruses, bacteria, mould, and fungi. It’s also a natural anti-inflammatory.
If you are using essential oils in your mix it is recommended that you store the sanitiser in dark plastic containers or just keep them in a dark place as sunlight (Ultra Violet) can break down the essential oils. This should not be a problem in small clear plastic containers kept in your bag.
Use caution with sanitiser containing these essential oils if your skin is light sensitive. Lemon and orange oils can cause photosensitivity, making your skin more sensitive to sun exposure. Although the oils are diluted, only a drop is required, you should exercise caution in their use. In any case, you should always test any hand sanitiser on a small area of skin before full use.
Apply the sanitiser to the centre of the palm of one hand using enough to form a small pool and rub the product completely over the surfaces of your hands, underneath your fingernails and your wrists. Too much will not generally give you more protection and just mean that you have to rub your hands for longer. Rub your hands together briskly for 20-30 seconds until your hands are fully dry. Allow the sanitizer to dry completely, without wiping your hands off or rinsing them with water. Any surplus should evaporate or soak into your skin.
Hand sanitiser should not be used to clean the screen of a mobile phone or tablet as it could damage the surface.
Ensure the concentration of alcohol to other substances when making hand sanitiser is correct as a high concentration could damage skin and pose safety risks. A high concentration could also put you at risk as it could be ignited by an open flame from a lighter or gas stove. In any case, you should never use an alcohol-based hand sanitiser near an ignition source.
Some recipes for hand sanitiser advocate the use of cheap vodka to introduce the alcohol content. Beware that the percentage of any alcohol-based drink that you use may not be above 60% and typically some vodkas are 40% but can range as high as 95% and this percentage is not what you are going to end up within your sanitiser mix. Here we are talking about the percentage of alcohol to the base liquid of the drink, basically water. To get an accurate percentage of alcohol in your sanitiser mix you would have to factor in the dilution effect of the water. So to get above 60% of alcohol in your sanitiser mix you would need a vodka with a high percentage of alcohol.
The amount of alcohol (ethanol) in spirits can be shown as proof or Alcohol By Volume (ABV). The proof is generally twice the percentage of alcohol by volume. Alcohol by volume (abbreviated as ABV, abv, or alc/vol) is a standard measure of how much alcohol is contained in a given volume of an alcoholic beverage (expressed as a volume per cent). It is defined as the number of millilitres (mL) of pure ethanol present in 100 mL (3.4 fl. oz) of solution at 20 °C (68 °F).
Hand sanitiser may not be effective in all situations especially on soiled or greasy hands. In this case, wash your hands. Just make sure you do it correctly. The US Centers for Disease Control and Prevention advises that you wet your hands, lather soap (use degreaser first if heavily soiled) in your hands (all over) for at least 20 seconds (the time it takes to mentally recite the words of the song happy birthday twice), then rinse and dry with a clean towel.
Be sure to lather the backs of your hands, between your fingers, and especially under your nails. Lathering and scrubbing your hands creates friction, which helps lift dirt, grease, and microbes from skin. Microbes are present on all surfaces of the hand, often in particularly high concentration under the nails, so your entire hand should be scrubbed.
Washing your hands is typically considered the best option. Evidence suggests that washing hands for about 15-30 seconds removes more microbes from hands than washing for shorter periods. The major groups of microorganisms (microbes) are bacteria, archaea (single-celled microorganisms similar to bacteria), fungi (yeasts and moulds), algae, protozoa (single-celled organisms such as Amoeba), and viruses.