Washing with soap – not just water – is vital to proper hygiene. While water is powerful at rinsing away dirt, it cannot easily remove soil or organisms that are attached to the hands. Soap is able to do this effectively, maximizing the rinsing benefit of the water.
Despite this, in recent times some manufacturers have promoted smaller and smaller hand soap dosages, enabling them to claim an economic benefit due to more doses per liter of soap. Sadly, such claims are not supported by evidence and indeed product testing has shown that low dosage levels do not, in many instances, result in cleaning any better than using water alone, leaving people misled and potentially at risk of spreading infections despite their own best and well-intended efforts.
Foaming hand soap has been demonstrated to enable a significant reduction in the environmental impact of commercial washrooms through a combination of water and energy savings and lower chemical impact compared to traditional liquid soaps. Foam soaps also cover more hand surface area per dose, providing a more effective wash.
A recent test concluded that a dose of 0.7ml is the lowest dose sufficient to comfortably spread across all surfaces of most people’s hands. Therefore, the test concludes that this dose is the best balance between required effectiveness and economics. Many manufacturers suggest using much lower doses however in testing, a dose of 0.4ml only covered 53 percent of the hand surface area and did not produce a cleaning result any better than water alone. Using the optimal amount of foam soap is necessary to produce clean, bacteria-free hands.
Learn more about proper handwashing techniques in this recent article entitled, "How Soap Provides a Protective Shield for Hardworking Hands".