DIY (Do-It-Yourself) Hand Sanitizer Formula
for Coronavirus COVID-19
Based on World Health Organization (WHO) Formula
Due to the outbreak and spread of Coronavirus (COVID-19) disease,
hand sanitizers are in short supply. You can easily make your own
sanitizer using drugstore materials: alcohol, glycerin, and hydrogen
peroxide.
1 cup 99% isopropyl alcohol -OR- 1 cup + 4 teaspoons 91%
isopropyl alcohol
1 Tablespoon hydrogen peroxide 3%
1 teaspoon glycerin
Water to make a total of 1 and 1/3 cups (1/3 quart)
3 cups 99% isopropyl alcohol -OR- 3.25 cups 91%
isopropyl alcohol
3 Tablespoons hydrogen peroxide 3%
1 Tablespoon glycerin
Water to make a total of 4 cups (1 quart)
To make 320 ml of hand sanitizer:
240 ml 99% -OR- 265 ml 91% isopropyl alcohol
15 ml hydrogen peroxide 3%
5 ml glycerin
Water to make a total of 320 ml
To make 1 liter of hand sanitizer:
750 ml 99% -OR- 830 ml 91% isopropyl alcohol
40 ml hydrogen peroxide 3%
15 ml glycerin
Water to make a total of 1000 ml (1 liter)
Mixing Instructions
Put on glasses or goggles to protect your eyes in case of
accidental splashing.
Combine the first three ingredients in a container.
Add clean water to reach the target volume.
Mix thoroughly by stirring or shaking.
Pour the mixture into dispensing bottles.
Label each dispensing bottle "Hand Sanitizer 75% Alcohol".
If your water is not absolutely clean, first boil it and allow it
too cool to room temperature. If your containers and ingredients are
not absolutely clean, allow 72 hours for the hydrogen peroxide to
kill any spores present, and keep the solution away from sunlight
and UV light, which break down the hydrogen peroxide.
The consistency of the final product is a liquid, not a gel. A spray
bottle is useful for applying the sanitizer to your hands without
dripping. Be sure to direct the spray at your hands. Label the
container and keep it away from anyone who might misuse it.
Isopropyl
alcohol 99.8%: 7515 ml Hydrogen
peroxide 3%: 417 ml
Glycerol 98%: 145 m
Water to make 10000 ml (10 liters)
To make 320
ml, multiply all quantities by 320/10000:
alcohol:
7515 ml x .0320 = 240 ml = about 1 cup (237 ml)
Hydrogen Peroxide 3%: 417 ml x .0320 = 13.3 ml = about 1
tablespoon (15 ml) glycerin:
145 ml x .0320 = 4.6 ml = about 1 teaspoon (5 ml) water
to make: 10000 ml x .0320 = 320 ml = about 1/3 quart
(315 ml)
To make 1 liter, multiply all quantities by 1000/10000 or
0.1
To make 1 quart, multiply all quantities by 946/10000 or
.0946 (a quart is 946 ml)
To make X ml, multiply all quantities by X/10000
If you are using isopropyl alcohol that is less than 100%, adjust
the amount that you use such that the pure alcohol content is the
same. For example, if the recipe calls for 750 ml pure alcohol (to
make 1000 ml of sanitizer), and you are using 91% alcohol to start:
750 ml = .91X
X= 750/.91 = 824 ml
In this case you would use less water at the end to achieve the same
75% alcohol content for the final 1000 ml of sanitizer.
If using ethanol instead if isopropyl alcohol, WHO's
formula calls for 80% ethanol content instead of 75%.
Ethanol 96%: 8333 ml
Hydrogen peroxide 3%: 417 ml
Glycerol 98%: 145 ml
Water to make 10000 ml
About the Ingredients
Isopropyl
alcohol (also known as rubbing alcohol and isopropanol) is the
ingredient that kills germs. It is sold in drugstores at different
strengths, typically 70%, 91%, and 99%. The target strength for the
hand sanitizer is 75%, so you need to start with at least the 91%
strength product.
Note: Do not use 99% alcohol directly as hand
sanitizer. Some water is needed for the sanitizer to work. The
final product must be between 60% and 95% alcohol, per CDC Guideline
for Hand Hygiene in Health-Care Settings
Glycerin (also
known as glycerol) is a clear, thick liquid used as a moisturizer in
skin care products and as a food igredient. It helps prevent your
hands from drying out. You can it in the drugstore with other skin
care products, and in health food stores.
Hydrogen
peroxide 3% is an antiseptic sold in drugstores with other
disinfectants. The small amount used in the formula is not effective
for sanitizing the skin. Its purpose to kill any spores in the hand
sanitizer itself, as alcohol is not effective against spores.
The WHO pamphlet recommends that you not add any other ingredients
such as fragrances or gelling agents. Some home formulations use
aloe vera gel, which might be OK, but it has not been evaluated for
possible interactions with other ingredients.
The formulas for making 1 quart, 1/3 quart, 320 ml, and 1 liter of
hand sanitizer are the same as the WHO formula, but with the amounts
scaled down for single-family use.
The final ingredient target concentrations are:
Isopropyl alcohol: 75% (v/v)
Hydrogen peroxide: 0.125% (v/v) (This is the fraction that is
pure hydrogen peroxide, not 3%)
Glycerin: 1.45% (v/v)
Ethanol (also
known as ethyl alcohol or grain alcohol), the alcohol in liquor, is
an alternative ingredient that is not as easily available as
isopropyl alcohol. Note that hard liquors are typically 80 to 100
proof (40% to 50% alcohol), too weak to work as hand sanitizer. If
you plan to use ethanol instead of isopropyl alcohol, see the
original WHO
pamphlet for the formula.
Effectiveness of the WHO Formula
The Centers for Disease Control and Prevention (CDC) recommends
ordinary soap
and water for washing hands at home. Use alcohol-based hand
sanitizers only when soap and water are not available.
Use the DIY hand sanitizer like any other. Apply enough to wet your
hands thoroughly. Gently rub all surfaces of both hands, including
fingertips and nails, until the alcohol evaporates. The CDC provides
hand sanitizer usage
and
safety information.
CDC
research has shown a hand sanitizer must be 60% to 95% alcohol
by volume to be effective. Most commercially sold sanitizer products
are 62% alcohol. The 75% strength used in this formula is even more
effective against viruses.
Note: Alcohol is a fuel. For fire safety information,
see the WHO
formula
pamphlet.
Disclaimer from WHO: "All reasonable precautions have been taken by
the World Health Organization to verify the information contained in
this document. However, the published material is being distributed
without warranty of any kind, either expressed or implied. The
responsibility for the interpretation and use of the material lies
with the reader. In no event shall the World Health Organization be
liable for damages arising from its use."
Other Formulas on the Web
Many hand sanitizer formulas on the Internet use too little alcohol
to achieve the required 60% minimum for effectiveness.
In the WikiHow article How
to Make Gel Alcohol Hand Sanitizer, Method 1 is generally
good, although usage of aloe vera gel has not been evaluated for
possible interactions with the alcohol. Method 2 adds essential oils
that have no sanitizing benefit. Method 3 uses 80 proof vodka as an
ingredient, which is only 40% alcohol to start, and dilutes it using
3 parts aloe vera gel to 1 part vodka, resulting in a final 10%
alcohol content.
The Good HouseKeeping article How
To Make A Natural Hand Sanitizer With 3 Simple Ingredients
uses plain vodka as an ingredient, diluted 3:1 by aloe vera gel and
other ingredients. Most vodkas are 80 proof or 40% alcohol, so the
resulting mixture is only 12% alcohol.
The Live Simply article DIY Hand
Sanitizer uses 2 parts rubbing alcohol (no strength specified)
and 3+ parts other ingredients. Even if 100% alcohol is used, the
final mixture is only 40% alcohol.
Isopropyl alcohol 99.8%: 7515 ml
Hydrogen peroxide 3%: 417 ml
Glycerol 98%: 145 m
Water to make 10000 ml (10 liters)
To make 320 ml, multiply all quantities by 320/10000:
alcohol: 7515 ml x .0320 = 240 ml = about 1 cup (237 ml)
Hydrogen Peroxide 3%: 417 ml x .0320 = 13.3 ml = about 1 tablespoon (15 ml)
glycerin: 145 ml x .0320 = 4.6 ml = about 1 teaspoon (5 ml)
water to make: 10000 ml x .0320 = 320 ml = about 1/3 quart (315 ml)