http://aem.asm.org/content/84/8/e00044-18.abstract
Hot-air hand dryers in multiple men's and women's bathrooms in three basic science research areas in an academic health center were screened for their deposition on plates of (i) total bacteria, some of which were identified, and (ii) a kanamycin-resistant Bacillus subtilis strain, PS533, spores of which are produced in large amounts in one basic science research laboratory.
Plates exposed to hand dryer air for 30 s averaged 18 to 60 colonies/plate; but interior hand dryer nozzle surfaces had minimal bacterial levels, plates exposed to bathroom air for 2 min with hand dryers off averaged ≤1 colony, and plates exposed to bathroom air moved by a small fan for 20 min had averages of 15 and 12 colonies/plate in two buildings tested.
Retrofitting hand dryers with HEPA filters reduced bacterial deposition by hand dryers ∼4-fold, and potential human pathogens were recovered from plates exposed to hand dryer air whether or not a HEPA filter was present and from bathroom air moved by a small fan. Spore-forming colonies, identified as B. subtilis PS533, averaged ∼2.5 to 5% of bacteria deposited by hand dryers throughout the basic research areas examined regardless of distance from the spore-forming laboratory, and these were almost certainly deposited as spores. Comparable results were obtained when bathroom air was sampled for spores.
These results indicate that many kinds of bacteria, including potential pathogens and spores, can be deposited on hands exposed to bathroom hand dryers and that spores could be dispersed throughout buildings and deposited on hands by hand dryers.
(Score: 2) by captain normal on Wednesday April 18 2018, @05:31AM (1 child)
Myth Busters covered this 5 years ago. Paper towels won.
https://www.youtube.com/watch?v=1pFww_EaLiY [youtube.com]
When life isn't going right, go left.
(Score: 2) by captain normal on Wednesday April 18 2018, @05:36AM
That link didn't carry through.
https://mythresults.com/down-dirty-earthquake-survival [mythresults.com]
When life isn't going right, go left.