Hypochlorous acid (HOCL) is not new. It is well known to the Centers for Disease Control and Prevention (CDC), the EPA, and many infection control experts as a less toxic option for sanitizing and disinfecting. HOCL is made in the human body as part of its immune system, so it is less toxic to humans than other sanitizer and disinfectant solutions. It has also been used for wound care and disinfecting water for over 100 years.

Hypochlorous acid is pure in that there are no synthetic fragrances or dyes added to the solution when made. It is made from salt, water and electricity to produce sodium hydroxide (NaOH) cleaner and HOCL sanitizer/disinfecting solutions.

Currently, the majority of on-site generation machines produce HOCL at a sanitizer level of under 500 parts per million (ppm) free available chlorine (FAC), as well as a sodium hydroxide cleaner/degreaser that is Green Seal certified for cleaning. There is also a machine on the market that does produce 500 ppm HOCL, a hospital-grade disinfectant.

One advantage to HOCL is that it does not cause or exacerbate asthma. It is also less irritating and toxic to humans and has good materials compatibility. HOCL has a neutral pH of 6 to 7, which allows for less dermal, eye and respiratory irritation to the worker. It is stable in a container for months, depending on the solution concentration, and it will not bleach color out of fabrics. Also, the mechanism of how HOCL kills microbes — by destroying their cell walls and bursting them open — does not allow them to adapt and form superbugs.

At low concentrations of 100 ppm, HOCL is a no-rinse food contact surface sanitizer that can be used safely in food service or daycare facilities. At higher dilutions, it kills the cold and flu, as well as C.diff spores, HIV and hepatitis. HOCL’s cost is low and, when coming from an on-site generator, it is sustainable, environmentally conscious, helps stop solid waste and cut pollution.

The use of aqueous ozone on-site generation in the caddy form supplemented with a wall-mounted unit for filling autoscrubbers, can deliver a sustainable, non-synthetic, no-rinse cleaning and deodorizing system that can alleviate cleaning levels and save time. Used in conjunction with an on-site generation system of HOCL, departments can create a powerful, proactive infection control and green cleaning program. 

HEIDI WILCOX, M.Sc., has a bachelor’s degree in Microbiology and Chemistry, a master’s in Environmental Engineering and is finishing up a doctorate in Toxics Use Reduction and Cleaner Production. She serves as the founder and president of WILCOX EVS Solutions, Haverhill, Massachusetts, a company specializing in helping facilities implement green cleaning and infection control systems, as well as understanding new and innovative technologies in the commercial cleaning industry.

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