Handwashing is the highest-value medical intervention in this entire app. It is free, it needs no skill, and it breaks the faecal-oral chain that every other page in the sanitation domain is arranged around.
It is also the first thing to lapse when water is rationed, which is precisely when it matters most.
Why soap beats sanitiser here
Washing properly
At least 20 seconds, and the technique matters more than the duration.
- Wet hands.
- Apply soap.
- Palms together.
- Back of each hand, fingers interlaced.
- Between the fingers.
- Backs of fingers against opposing palms.
- Each thumb, rotating, clasped in the other palm.
- Fingertips and nails into the opposite palm.
- Wrists.
- Rinse thoroughly.
- Dry.
The missed spots are consistent across everybody: thumbs, fingertips, nails and wrists. Those four are the ones to be deliberate about.
Drying matters. Wet hands transfer organisms far more readily than dry ones, so a shared damp towel undoes the wash. Use a clean towel, change it often, or air dry.
Keep nails short. In a household with limited washing, long nails hold material that no amount of hand rubbing reaches.
The moments that matter
Not all handwashing is equal, and when water is short you prioritise.
Numbers 1 and 3 are the pair that breaks the chain. If water is so short that only two washes a day are possible, those are the two.
Site handwashing where the activity is, not where the sink is. A container by the toilet, one by the compost heap, one at the kitchen. Handwashing that requires walking somewhere is handwashing that gets skipped.
Washing with very little water
- A trickle beats a stream. You need enough to wet, and enough to rinse, and no more.
- Wet, turn off, lather thoroughly, then rinse. Running water through the lathering step is where most of it is wasted.
- Half a litre is ample for a proper wash with a tippy-tap. A running tap uses many times that.
- Catch the runoff. It is greywater and goes to flushing or the garden, per greywater reuse.
- Use the least clean acceptable water. Handwashing does not need drinking-quality water, provided the water is not itself contaminated with faecal matter. Filtered rainwater is fine. Untreated stream water below farmland is not.
What it costs in water
The page has said handwashing is the first thing to lapse when water is rationed, and has given a figure for a wash, and never put the two together. The arithmetic is worth having because it is smaller than people fear.
A sixth of the household's water for the single most effective medical intervention available is a good trade, and it is the calculation to make before rationing decisions get made in a hurry.
With a running tap the same washing consumes several times that, which is why the tippy-tap is on this page rather than as a curiosity. The device is the difference between handwashing being affordable under rationing and being the thing that gets cut.
It does not need drinking-quality water. Filtered rainwater, or stored washing water, is entirely adequate provided it is not itself contaminated with faecal matter. That takes the whole demand off the drinkable store, which is the same argument the emergency bath store page makes about washing generally.
And the runoff is not lost. It is greywater, and it flushes the toilet. See reuse greywater safely and getting rid of greywater.
Making soap last
- Bar soap lasts far longer than liquid. A bar gives many more washes per gram and stores indefinitely. Stock bars, not bottles.
- Keep bars dry between uses. A bar sitting in water dissolves away, and a draining dish doubles its life.
- Unwrap bars and let them dry out for a few weeks before storing. Harder soap lasts longer.
- Cut bars in half. A smaller piece in use means less surface area dissolving.
- Collect the slivers and press them together, or dissolve them in hot water to make a jelly.
- Soap does not expire. Properly stored, it keeps for years, which makes it one of the best things in the house to stockpile deeply.
- You need far less than you use. Most people use several times more than necessary for both hands and laundry.
- Wood ash and water makes lye, and lye plus fat makes soap. That is the genuine long-term answer and it lives in the making and mending domain. It is worth knowing that a household with wood, fat and time is not permanently without soap.
Soap substitutes, honestly:
- Wood ash on its own is mildly alkaline and does cut grease. It is harsh on skin and better for pots and laundry than for hands.
- Soapwort grows in Britain and lathers genuinely. Mild and worth knowing.
- Plain water and vigorous rubbing removes a substantial share of what soap would, and is far better than nothing. If there is no soap, wash for longer and rub harder, because friction is the mechanism anyway.
What to stock
- Plain bar soap, in quantity. It is cheap, it never expires, and it is the highest-value hygiene item you can store.
- Washing soda and bicarbonate, which stretch soap and store indefinitely.
- Alcohol hand sanitiser at 60% or above, as the no-water fallback, not the primary.
- Clean cloths or small towels, several, so drying does not undo the washing.
- A tippy-tap setup, or the bits for one.
- Nail brushes, which are cheap and disproportionately effective.