(1) Bacteria were identified in the Entonox mask both before and after cleaning. Although sterility is not required in these masks, as these masks are designed to provide rapid and direct pain relief via the lungs, significant contamination with certain organisms may introduce further complications in an already traumatised patient.
(2) It would seem that the general process of vehicle cleaning needs further consideration. In most cases, vehicle cleaning resulted in successful elimination of bacteria from previously
contaminated sites.However, on several occasions this was not the case and cleaning of sites either had no effect on reducing bacterial contamination, or resulted in the introduction of
new species of bacteria.