Monday, June 21, 2021

CD vs VPHP: Distribution Comparison

We have long discussed the factors to an effective decontamination.  They are:

  • The ability of the process to eliminate the target pathogen
  • The ability of the decontaminating agent to contact the pathogen
  • The ability of the decontaminating agent to accumulate enough contact time

 Chlorine dioxide (CD) and hydrogen peroxide are the two most common methods for room decontamination.  Their ability to consistently meet these factors is where these methods contrast from one another.  These differences stem from their chemical properties, as hydrogen peroxide is a liquid at room temperature that is flash vaporized at 228°F.  This differs from chlorine dioxide as it is a gas at room temperatures with a boiling point at use concentration of -40°F.  Vapors do not diffuse throughout a space as well as gasses, making it far more challenging to achieve complete coverage of an area when using hydrogen peroxide vapor.

Hydrogen peroxide manufacturers have classified hydrogen peroxide as being “poor at passive diffusion.”  Studies have shown it having difficulty going around objects within a space, effectively creating “shadow areas” where hydrogen peroxide is either not reaching, or is reaching at lower concentrations.  It also suffers from condensation as typically the environment being treated is below 228 F.  As such, the further hydrogen peroxide travels, the cooler it will become.  As it cools, it will start to condense and become too heavy to stay afloat in the air, limiting the distances it can effectively treat.  Chlorine dioxide being a true gas at room temperatures will follow the gas laws which state that it will uniformly fill up the environment that it is introduced into.  This means that the gas will reach all surfaces, and it will do so at an even concentration.

Logic tells us that a decontaminating agent will not be effective if it doesn’t come into contact with the pathogens.  As the target environment gets larger, or more complex with equipment and items inside of it, hydrogen peroxide has a great chance of failure.  Chlorine dioxide however, is unaffected by temperature, size, shape, and how full an environment is, maintaining its ability to distribute throughout the area and contact pathogens on all surfaces throughout.  This is why chlorine dioxide is able to be trusted for the toughest applications.

To learn more, join our webinar this Thursday at 2pm Eastern by clicking here.