First Threshold

For years, the process surrounding the choice of an agent for room decontamination never focused on finding the best agent available, but rather the agent with the least drawbacks. Spraying and wiping was labour intensive, and prone to rely on the human element for its success. Formaldehyde is a carcinogen and requires neutralisation as well as a post-neutralisation wipe down. Vapour phase hydrogen peroxide (VPHP) has distribution issues, needs tight temperature controls, and employs a lengthy cycle development phase. It was not until chlorine dioxide gas came into view that there was a clear frontrunner in the room decontamination market.

There are three factors constituting a successful room decontamination. A decontaminant must be completely distributed inside of the room – an agent cannot kill what it does not touch. The decontaminant must exhibit total penetration, displaying the ability to reach inside cracks and crevices, for the same reasons. The decontaminant must then remain in contact with all surfaces for a prescribed time, depending upon the concentration of the decontaminant used. A room can safely be deemed decontaminated only upon knowing that the room’s atmosphere as well as every surface has been exposed to the agent under the correct concentration and contact time.

PHYSICAL PROPERTIES

The inherent properties of chlorine dioxide gas allow for the assurance of a complete decontamination, whether for chambers, rooms or facilities. By definition, a gas fills the space it is enclosed within uniformly, giving chlorine dioxide gas the necessary distributive ability for proper decontamination that vapour decontamination methods cannot attain. Spraying and wiping lacks the effectiveness of chlorine dioxide gas, as it is subject to human skill and error. It is easy to miss a spot when spraying and wiping a decontaminating agent around a room, as many objects have corners and protrusions which can block the agent from contacting everywhere. Chlorine dioxide gas’ ability to penetrate into cracks and other small spaces is also determined by its gaseous state. To a true gas, nooks and crannies are just part of the enclosure, one more place to which the gas will diffuse.