In the UK there is a problem with MRSA cross-contamination in hospitals. This antibiotic resistant bacterial infection is rarely fatal, but can lead to complications in wound healing and recovery.

Hospital staff can transfer the infection from patient to patient on their hands. Hand-washing between patients with water and soap/antibacterial wash is effective if the water is sufficiently hot, and if thorough scrubbing is carried out, but this also causes skin problems for staff (who, on a busy ward, might need to wash hands hundreds of times a day) - and as a result, is often not done thoroughly enough.

In some circumstances, and antibacterial "waterless" alcohol gel can be used, but this is very harsh on the skin, and can lead to dermatitis.

I propose a hand-wash station with a shallow water-trough, automatically filled with water/soap at the right temperature, with powerful piezoacoustic actuators to create an intense ultrasonic field in the water. Scrubbing of the hands is achieved by microcavitation in the water, without the abrasive effect on the skin of a scrubbing brush. Once washing is complete, the water is drained automatically, ready for the next user.
-- Frankx, Aug 16 2006

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