The World Health Organization publishes two hand sanitizer formulas designed for local production, particularly in healthcare settings or regions where commercial products are unavailable. Both use only four ingredients: an alcohol (either ethanol or isopropyl alcohol), a low concentration of hydrogen peroxide, glycerol, and distilled or boiled water. The formulas were developed to be simple enough to prepare with basic equipment while still meeting clinical-grade disinfection standards.
Formula 1: Ethanol-Based
This formulation produces a final concentration of ethanol 80%, glycerol 1.45%, and hydrogen peroxide 0.125%. For a 10-liter batch, the ingredients are:
- Ethanol 96%: 8,333 ml
- Hydrogen peroxide 3%: 417 ml
- Glycerol 98%: 145 ml
- Distilled or boiled water: enough to bring the total volume to 10 liters
Pour the ethanol into a 10-liter glass or plastic bottle with a screw-top lid, add the hydrogen peroxide and glycerol, then top up to 10 liters with water. Shake gently to mix.
Formula 2: Isopropyl Alcohol-Based
This version targets a final concentration of isopropyl alcohol 75%, with the same 1.45% glycerol and 0.125% hydrogen peroxide. For a 10-liter batch:
- Isopropyl alcohol 99.8%: 7,515 ml
- Hydrogen peroxide 3%: 417 ml
- Glycerol 98%: 145 ml
- Distilled or boiled water: enough to reach 10 liters
The mixing process is identical. Use a graduated container, add ingredients in order, top up with water, and shake gently.
What Each Ingredient Does
Alcohol is the only active germ-killing ingredient in both formulas. At 80% (ethanol) or 75% (isopropyl), it destroys most bacteria and many viruses on contact by breaking down their outer membranes. The two formulas are roughly equivalent in effectiveness, so the choice depends on which alcohol is locally available.
Glycerol at 1.45% serves as an emollient, protecting skin against the dryness and cracking that comes with repeated use. Without it, healthcare workers using sanitizer dozens of times per day would quickly develop dermatitis. Glycerol is thick and can make the solution feel slightly sticky, but it’s essential for skin tolerance over time.
Hydrogen peroxide at 0.125% is not there to disinfect your hands. Its job is to kill any bacterial spores that might be contaminating the bottle or raw ingredients during production. At such a low concentration, it has no meaningful antiseptic effect on skin, but it helps ensure the finished product stays uncontaminated in storage.
Production Safety
Both formulas are highly flammable. The finished ethanol-based product has a flash point of 17.5°C (about 64°F), and the isopropyl version ignites at 19°C (66°F). That means at normal room temperature, these liquids can catch fire if exposed to a spark or open flame.
The WHO guidelines are specific about safety precautions. Production and storage areas should be cool or air-conditioned, with no open flames or smoking permitted anywhere nearby. Undiluted ethanol is even more dangerous, with a flash point as low as 10°C, so the WHO recommends diluting it to the final concentration as quickly as possible rather than storing it at full strength.
Batches should not exceed 50 liters unless you’re working in a pharmacy with specialized ventilation. If a fire does break out, use water or aqueous film-forming foam. Standard fire extinguishers can spread an alcohol fire rather than put it out.
Storage and Shelf Life
Finished hand rub should be stored away from heat and flames in glass or plastic bottles with screw-top lids. The WHO recommends letting each batch sit for 72 hours before use, giving the hydrogen peroxide time to eliminate any spores introduced during production.
In healthcare facilities, keep only the amount needed for day-to-day use on any given ward or unit. Bulk storage must comply with local fire regulations, and any facility storing more than 50 liters needs a designated flammable-materials cabinet or storage room. The locally produced product should also be labeled with its composition, the production date, and the batch number to allow tracking.
Scaling Down for Smaller Batches
The WHO provides the formula in both 10-liter and 1-liter versions. To make 1 liter of the isopropyl alcohol formula, for example, use 751.5 ml of isopropyl alcohol 99.8%, 41.7 ml of hydrogen peroxide 3%, and 14.5 ml of glycerol 98%, then top up to 1,000 ml with distilled or boiled and cooled water. The ethanol formula scales the same way: divide the 10-liter quantities by 10.
Use a graduated flask or measuring cylinder for accuracy. The alcohol concentration is what determines whether the sanitizer actually works, so precision matters more here than in typical household mixing. If the final alcohol percentage drops too low, the product won’t reliably kill pathogens.