As people get ready to reopen many businesses, SAGE (the Scientific Advisory Group for Emergencies that provides scientific and technical advice to support government decision makers during emergencies) has reviewed the evidence on the spread of COVID-19 and the efficiency of mitigation measures. One of the issues considered is washroom hygiene with a large amount of useful information on cleansing and air flows.
Specifically on hand drying the documents states: Replacement of jet dryers with paper towels
Rationale: Jet air dryers can aerosolise microorganisms from poorly washed hands. Incomplete drying of hands means that contamination can persist on hands.
Evidence: Mechanistic studies to show microbial dispersion and studies using surrogate microorganisms show persistence of contamination. No direct evidence for transmission.
Practical considerations: Relatively easy action to temporarily take dryers out of action and provide paper towels. Need to consider the management of paper towel waste. Longer term there are cost and energy implications.