iDE Global

Clean hands, better lives

Designing handwashing solutions

You’ve heard the phrase, “if you build a better mousetrap, the world will beat a path to your door.” People have taken this literally, as there are over 4,400 patents issued by the U.S. Patent and Trademark Office for mousetraps. But if you really want to change the world, focus on designing a better method for people to wash their hands.

Water. Soap. Habit.

The biggest barrier to handwashing is not always the availability of water or soap, but rather knowledge. Making the connection between dirty hands and disease is the first step. The second is building the habit and making it easy for people to incorporate it into their daily routine.  

iDE PC Hand Hygiene

(Photo by David Graham/iDE)

Handwashing is not a trivial matter. It is considered one of the most effective ways to reduce diarrheal diseases, which kill more than 1.8 million people every year, most of them children. The number of patents issued for handwashing devices? Less than one percent of the total for mousetraps.

How do you wash your hands?

The Center for Disease Control suggests following these five steps:

  • Wet your hands with clean, running water (warm or cold), turn off the tap, and apply soap.
  • Lather your hands by rubbing them together with the soap. Be sure to lather the backs of your hands, between your fingers, and under your nails.
  • Scrub your hands for at least 20 seconds. Need a timer? Hum the “Happy Birthday” song from beginning to end twice.
  • Rinse your hands well under clean, running water.
  • Dry your hands using a clean towel or air dry them.

But what if you don’t have access to a sink and piped water? For most of the world’s rural households, the water they use from lakes and wells is often contaminated and soap unavailable. Even if the water was clean to begin with, it is often stored in an open container where it is easily re-contaminated, either by animals, children playing with it, or people transferring water to smaller containers with dirty hands or jugs. 

We can’t put sinks and indoor plumbing into all the rural households in the world. So we need something to fill the gap for those people who don’t have them.

Designing a new device

Building upon our successes in getting toilets in Cambodian homes, iDE is developing options for handwashing. Like the latrines we design, these solutions have to be affordable, desirable, and feasible for local manufacturers and their customers.

Following our human-centered design principles, iDE talks to the intended users to identify if and how they currently wash their hands, if they believe handwashing is necessary, and when they believe it should be done. Based on these insights, they ask customers what it would take to increase how often they wash their hands and what they would expect a handwashing option to look and act like.

In Ghana, our design team addressed the specific needs for customers who had recently installed the Sama Sama latrine. We knew that handwashing options created for Cambodia would not work in Africa: water is scarcer and manufacturing methods more limited. Based on interviews, three directions were tested: (1) a water bucket with a hose attached located inside the latrine, (2) a water bucket with tap located outside the latrine, and (3) a combination “jerry can” and a bowl (called a “calabash”) that had small holes in the bottom for the water to drip through.


The third option was a combination “jerry can” and a bowl (called a “calabash”) that had small holes in the bottom for the water to drip through. Users liked this option the best, as it was easy to use (without bending over), was perceived as using less water, and minimized the chance for clean hands to be recontaminated by touching something that had been touched by dirty hands. This photo shows the final product installed.

I De Pc Hygiene Ghana 3X2

(Photo by Dave Schutz/iDE)

A device is only part of the solution

Even with a handwashing device, another challenge is getting users to consistently practice proper handwashing behavior. Barriers and accelerators for handwashing differ from place to place and from culture to culture. In Vietnam, even households who are aware of the importance of handwashing are unlikely to actually wash their hands in practice. In a recent survey conducted by iDE, 58 percent of respondents had a good understanding of hand hygiene, and 69 percent have handwashing facilities, but only 8 percent reported washing hands frequently. More effective behavior change messaging is needed to help households translate knowledge into action.

iDE is currently testing different ways to trigger people to wash hands, including stickers about handwashing inside latrine doors and placing soap in convenient handwashing locations.

To design more effective hand hygiene campaigns, iDE wants to learn more about households’ motivations and barriers. Questions to be addressed include:

  • Is there a need for different messages for different demographics, such as toilet paper users and bidet hose users?
  • Will handwashing increase if soap is near the faucet closest to the toilet?
  • What is the likelihood of rural households keeping their preferred bar soap close to the toilet for handwashing?
  • What physical reminders are best suited to increase handwashing?
  • How can households’ preference for brand name soaps be leveraged to improve handwashing behavior?
  • How can behavior change for hand hygiene be integrated into iDE’s current sanitation marketing interventions?

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