Decontamination foam (known commonly as Decon foam) is a spray-on cleaning solution that, due to its physical properties, has a longer residence time on contaminated surfaces than regular liquids and thus provides efficient decontamination of biological and chemical contaminants (e.g. chemical warfare agents, anthrax spores or other toxic industrial materials (TIM)). The composition of decontamination foams is essentially water and a surfactant, creating an aqueous film forming foam that various reactive chemicals are then added, diminishing the amount of contaminants adhering to a surface and forming less hazardous products. Common reactants are hydrogen peroxide and quaternary ammonium complexes (QACs).
Benefits of decontamination foamEdit
The two main benefits of decontamination foam over liquid decontaminants (chlorine, decontamination solutions, etc.) are its effectiveness on non horizontal surfaces and its high air to liquid ratio. Other decontaminants are difficult to apply to walls and ceilings due to poor adhesion, however decon foam is much better at adhering to surfaces, which increases the amount of time for the decontamination reaction to take place. Additionally, the high air to liquid ratio allows the foam to be used without over-applying the decontaminant. This high ratio also allows a small amount of liquid to cover a relatively large area in the event of a major contamination.
Soap cannons and other foam delivery systems in practiceEdit
The LAX airport soap cannon can spray large quantities of decon foam on crowds of potentially exposed persons, e.g. to decon an entire planeload of people who might be victims of a nuclear, chemical, or biological agent release.
Mixing and useEdit
Decon foam often comes in multiple bottles, that, when mixed, combine to form the decontamination solution. The bottles should be kept separate until needed as the foam may begin to lose effectiveness after mixing. After these bottles are mixed together, the foam can be applied by spraying it on a contaminated area or by manual application.