Portable On-Demand Hypochlorous Acid Disinfectant Cleaners

The DoD STED Program is currently demonstrating portable on-demand hypochlorous acid (HOCl) generators and the HOCl disinfectant cleaner solutions they produce for use in operations at Department of Defense (DoD) and National Aeronautics and Space Administration (NASA) facilities. These are small portable tabletop devices that utilize electrolysis of onsite water and premeasured salt and vinegar to produce on-demand electrolyzed water containing the active ingredient HOCl. The resulting solution is a hospital-grade disinfectant cleaner that is EPA registered; Kist G, List H, List N and List Q; Green Seal certified; and allergen free.

DoD STED Program Logo

Traditional disinfection utilizes more hazardous, irritating, and allergenic premade chemical products containing hypochlorites, quaternary ammonium compounds, hydrogen peroxide, peracetic acid, or phenols. These are used at DoD medical, veterinary, research, childcare, recreation, food service, hospitality, retail, and administrative facilities. Compared to on-demand generation of HOCl cleaners, these products pose higher hazard and sensitivity risks, can factor single-use packaging and higher shipping weight into product pricing, and pose higher supply chain negative impacts (e.g., material waste and/or pollutant emissions). In contrast, on-demand generation of a non-toxic and allergen-free Environmental Protection Agency (EPA) registered disinfectant cleaner mitigates pollution impacts associated with the manufacturing, shipping, and disposal of traditional disinfectant and cleaning products while presenting significantly less hazards and allergy concerns. As a multipurpose disinfectant and cleaner, the product may be able to replace multiple specialty cleaners at a cost savings while reducing the need for chemical storage and tracking.

Section 856 of the FY25 National Defense Authorization Act requires DoD to give procurement preference to cleaning products identified under the Safer Choice program or an independent third-party organization that provides certifications in a manner consistent with Safer Choice.

Before portable on-demand HOCl disinfectant cleaners are utilized by the Military Departments and DoD Components, their performance must be proven to meet DoD requirements.

The following systems were selected for demonstration, as they are the only such systems determined to be EPA-registered under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA):

• Mention of or referral to commercial products, services, and manufacturers herein is provided for informational purposes only and does not constitute endorsement by, nor the official policy or position of, the Department of Defense (DoD), any of its Components, or the U.S. Government.

Field demonstrations of portable on-demand HOCl disinfectant cleaners were conducted at the following DoD installations and co-located federal facilities to evaluate their performance in Military and NASA operational environments and to raise awareness of portable on-demand hypochlorous acid disinfectant cleaner technologies.

• Pentagon Athletic Center (gym)
• Naval Support Activity Bethesda (medical facilities administrative)
• Joint Base Lewis-McChord (office administrative and maintenance administrative)
• NASA Armstrong Flight Research Center (gym)

The demonstration plan outlined the demonstration activities that would be performed, provided an overview of the sites, summarized the selected facilities, and identified their requirements, the key performance criteria, and the products to be evaluated. Additionally, the plan noted the data to be collected, methods of analysis, and roles and responsibilities of demonstration participants and stakeholders.

The following Table contains the key performance criteria that the DoD and NASA stakeholders established to evaluate and validate that these portable on-demand HOCl disinfectant cleaner products met the participants’ requirements.

Table 1: Demonstration Performance Criteria

• Feedback indicated the demonstration portable on-demand HOCl disinfectant cleaner device was easy to use. All sites noted there were no issues and none were observed by the Project Team during site visits.
• Feedback indicated the demonstration portable on-demand HOCl disinfectant cleaner device features were all easy to use. This included the start button, fill lines, status light, and activator capsules. All sites noted there were no issues and none were observed by the Project Team during site visits.
• Feedback indicated the demonstration portable on-demand HOCl disinfectant cleaner device functioned properly at all sites. There were two comments related to the ancillary spray bottles. One site noted that some of the sprayers occasionally clogged, but the issue could be remedied and wasn’t a major concern. Another site recommended that the manufacturer add something to the 12 oz bottle on which the user can write the date the solution was created. The manufacturer now offers peelable labels to address this need. No other related issues were reported or observed.
• Feedback indicated the demonstration portable on-demand HOCl disinfectant cleaner was effective at disinfecting and as effective as baseline products. This was mostly based on the product’s pesticide label and site observations. Per Army Medical Technical Bulletin 531 (Facility Sanitation Controls and Inspections), most applications require an EPA-registered disinfection product that is effective against the greatest spectrum of fungi, viruses, and bacteria. Per the FIFRA label process, the manufacturer submitted required efficacy lab testing to EPA, which EPA validated in approving the claims on the product label.
• Those validated and approved claims, based on the required lab testing, include the following: Proven to kill 99.9% of (bacteria) (germs) (such as) (Salmonella) (and) (MRSA) (Methicillin resistant Staphylococcus aureus); Kills 99.9% of germs including Staph, MRSA, Salmonella, Listeria and the viruses that cause flus; Kills 99.9% of odor-causing bacteria; (Destroys) (Controls) (Eliminates) (Kills) (99.9%) of (Germs) (Bacteria) (Viruses) (Bacteria & Viruses) (Flu virus) (Norovirus) (Staph) (MRSA) (Salmonella) (Listeria); Kills 99.9% of germs on virtually any surface; Kills (controls) (removes) (stops) mold (mildew) (fungus) (athlete’s fungus). In addition, the demonstration product is on EPA Lists G, H, N, and Q for products effective at killing norovirus, MRSA, coronavirus (COVID-19), and tier 1 and 2 emerging viral pathogens. It also meets surface disinfection requirements for the Occupational Safety and Heath Administration’s Bloodborne Pathogens Standards.
• The only target pathogen that demonstration sites raised as a concern that the product cannot completely kill at its current free available chlorine concentration is Clostridium difficile, though the manufacturer stated they could produce a device capable of generating a solution with sufficient chlorine concentration to kill the organism and all its spores if there is market interest. There are pre-packaged hypochlorous acid products at such higher chlorine concentrations listed on EPA List K for products effective at killing Clostridium difficile spores. All sites raising this pathogen as a concern were part of Defense Health Agency (DHA) and most Clostridium difficile infections originate in health care settings rather than among the general populace.
• The only analytic disinfection effectiveness testing performed at demonstration sites was the use of chlorine test strips by JBLM Environmental Division. Although readings from such test strips can be imprecise (i.e., subject to individual perceptions of color) and individual strips can vary in quality, use of test strips for field validation of chlorine-based disinfectants is the method put forth in Medical Technical Bulletin 531, presumably owing to the ease, availability, and low cost of such testing compared to other methods. A hypochlorous acid solution with a free available chlorine concentration of 200 parts per million (ppm) is generally recognized as effective against bacteria, viruses, and fungi. The readings taken by JBLM Environmental Division personnel using chlorine test strips were in line with the manufacturer’s claims and the desired chlorine concentration (i.e., 200 ppm or above of free available chlorine) throughout the two-week service life period following the creation of the solution in the device.
• The EPA recognizes it is unrealistic to expect all companies to have the resources to individually test against dozens of potential pathogens and makes accommodation for this via the “broad spectrum disinfectant” designation. The term “broad spectrum” indicates that the disinfectant has undergone standardized testing and has been shown to be effective against both Gram-positive and Gram-negative bacteria. By meeting these criteria, the disinfectant is considered effective in a variety of settings where different types of microorganisms might be present, making it suitable for general use in health care, commercial, and residential environments. In addition, the demonstration disinfectant cleaner meets EPA’s additional requirement for “hospital-grade” disinfectants, i.e., effectiveness in killing Pseudomonas aeruginosa. The demonstration product thus meets EPA’s criteria to be sold as a “broad spectrum disinfectant” and a “hospital-grade” disinfectant.
• Demonstration product dwell/kill time during the initial demonstration was 10 minutes, per the prior specific test methods used and test results reviewed and approved by EPA. Some sites commented that this dwell/kill time was too long. Subsequently, the manufacturer conducted additional testing that was approved by EPA showing a 2-minute dwell/kill time for the following target pathogen indicators:

The manufacturer is currently conducting efficacy testing against Tuberculosis as an indicator for acid-fast bacteria. Initial tests also show a 2-minute dwell/kill time, though testing must be completed and approved by EPA.

• Feedback indicated the demonstration portable on-demand HOCl disinfectant cleaner was effective at cleaning and as effective as baseline products. This feedback aligns with the results of third-party (Toxic Use Reduction Institute, the University of Massachusetts) testing performed for the manufacturer, comparing the cleaning effectiveness of the demonstration product against common household products. That testing showed the demonstration product to be similar or better in its cleaning effectiveness compared to the common household products. Similarly, the demonstration product is certified under Green Seal Standard GS-37. Not only does this mean the product meets the environmental and safety requirements of the Standard, but also its criteria for commercial cleaning effectiveness. It also satisfies the FY25 National Defense Authorization Act Section 856 requirement for cleaning products.
• Feedback indicated the demonstration portable on-demand HOCl disinfectant cleaner was effective at deodorizing (via killing odor causing bacteria), though not all sites used and evaluated the product in this regard and comparison to baseline products was mixed. While the housekeeping contractor at one site did not use the demonstration product for the purpose of deodorizing, site facilities personnel noted that they had a sewage back-up in the building bathroom during the demonstration. When they sprayed the demonstration product on the residual sewage, the product was effective at neutralizing the foul odor. Another site concluded that the demonstration product was effective at deodorizing but stated they have other cleaning solutions and products that deodorize and kill odors for longer. Conversely, a third site stated that the demonstration product was more effective at deodorizing than their baseline products.
• Feedback from two sites indicated the demonstration portable on-demand HOCl disinfectant cleaner was effective at reducing the recurrence of odors, though not at a level comparable to baseline products. However, this feedback conflated deodorizing with air freshening (i.e., application of a fragrance as an odor coverup). Both sites utilized fragranced baseline cleaners. The demonstration product only has a light chlorine odor and is not intended to add fragrance to coverup odor.
• None of the demonstration sites had a need to treat mold or mildew and thus provided no feedback regarding the portable on-demand HOCl disinfectant cleaner’s effectiveness at killing mold or mildew. The EPA approved the product’s efficacy testing and label claims, which demonstrate a 2-minute dwell/kill time for fungi and label effectiveness claims against mold, mildew, and other fungi.
• Feedback indicated that all sites used the demonstration portable on-demand HOCl disinfectant cleaner for cleaning applications aligned with the product’s intended uses. Specifically, these included multipurpose cleaning, glass cleaning, and floor cleaning on sinks, toilets, countertops, glass and mirrors, conference/office/breakroom tables, cubicles, whiteboards, gym equipment and mats, carpets, flooring, and walls.
• Feedback indicated that all sites used the demonstration portable on-demand hypochlorous acid disinfectant cleaner on cleaning surfaces aligned with the product’s intended uses. Specifically, these included steel, porcelain, glass and mirror, wood, plastic/vinyl/veneer, whiteboards, rubber/thermoplastic, cloth/fabrics, carpet, tile, and painted drywall, brick, and cement.
• Feedback indicated that all sites used the demonstration portable on-demand HOCl disinfectant cleaner to remove residues aligned with the product’s intended uses. Specifically, sites used the demonstration product to remove dust/soil/particles/grime, sweat, scuffs, soap scum, streaks/fingerprints, sticky substances, and oil and grease spots. Mixed feedback was received pertaining to whiteboard cleaning, with some sites reporting that the product worked well to remove marks and other sites stating that it did not perform as well as baseline products. This evaluation likely depends on the specific whiteboards, markers, and baseline products used. One site noted that the product could leave streaks if applied with a saturated cloth or paper towel but the issue did not occur if a drier cloth or towel was used.
• Feedback indicated that demonstration portable on-demand HOCl disinfectant cleaner caused no negative impacts to cleaning surfaces and effectively removed residues from those surfaces. One site noted that the demonstration product did great on glass and stainless-steel surfaces and worked well on whiteboards, including clearing off old marks. Another site noted that the product cleaned up oil and grease residues in their maintenance administrative areas much better than their baseline products. When used on the floor in the bathroom where the floor was a very dark color, the product completely removed the residue and brought the tile back to its original color. The same site also reported that the demonstration product removed spots on carpet.
• Feedback indicated that the demonstration portable on-demand HOCl disinfectant cleaner was easy to apply. All sites used trigger spray bottles to apply the product via spray and wipe and/or spray and leave method.
• Feedback indicated that the requirement to generate new solution every two weeks, based on the two-week disinfectant service life, did not pose hardship or difficulty. Most sites used the demonstration product at a high volume, resulting in the need to generate new product more frequently than every two weeks. These sites simply generated solution as needed. Three sites at two of the locations did not use all product within every two-week period but had no issue generating new solution based on that schedule.
• Feedback indicated that the need to track the two-week disinfectant service life of the demonstration portable on-demand HOCl disinfectant cleaner did not pose hardship or difficulty. Sites that used sufficient volume of product to generate new solution more frequently than every two weeks did not have to track service life since all in-use product was used up within the two-week period. The other sites used either a log, bottle labeling, or a calendar entry to track the service life.
• Feedback indicated that disposal of unused demonstration portable on-demand HOCl disinfectant cleaner at the end of the two-week service life period did not pose hardship or difficulty. Sites that used sufficient volume of product to generate new solution more frequently than every two weeks did not have any unused product to dispose. Two sites at one location, through prior coordination with and approval from the wastewater treatment plant provider, disposed of remaining product by pouring it down the sanitary sewer. Another site disposed of the small amount of remaining product by pouring it on impermeable hardscape and allowing the hot summer weather to quickly evaporate it (the product being composed of ~98% water).
• Feedback indicated that the ease of using the demonstration portable on-demand HOCl disinfectant cleaner solution was comparable to baseline products for three sites and better than baseline products for two sites. No sites reported that demonstration product ease of use was worse than that of baseline products.
• Feedback indicated that quantity of use for the demonstration portable on-demand HOCl disinfectant cleaner solution was comparable to that of baseline products. Although one site indicated that there was a change in quantity of use, their comments pertained to using a dispensing system for baseline products and not having to measure product since it was automatically diluted to the appropriate amount. The demonstration product accomplishes something similar via use of premeasured activator capsules and device ‘fill to’ lines. The comments do not directly pertain to a different quantity of use. Technically, the demonstration product at dilution does utilize more ‘concentrate’ insofar as the site’s baseline product requires 0.5 ounces of product per gallon and the demonstration product utilizes 1.35256 ounces of salt/water/vinegar mix per gallon. However, at least 70% of the activator capsule content is also water, so the maximum ‘concentrate’ amount would be less than baseline (0.405768 ounces versus 0.5 ounces).
• Feedback indicated that two sites already using PPE during disinfectant and/or cleaner application continued to do so when using the demonstration portable on-demand HOCl disinfectant cleaner even though the manufacturer and Safety Data Sheet state that no PPE is required. This was based on habit and caution rather than direct concerns. The three other sites used no PPE and did not experience any health or safety issues or adverse physical impacts.
• Feedback indicated that no sites found the portable on-demand HOCl disinfectant cleaner odor to be objectionable or problematic. One site noted that the odor was less strong than their baseline disinfectant cleaner, which is fragranced. Another site stated that some individuals sensitive to chlorine odor did not like the demonstration product’s slight chlorine odor, preferring other odors to it but not necessarily finding it objectionable or problematic. A third site stated that some personnel commented on the demonstration product’s slight chlorine odor, but they did not find it objectionable or problematic.
• Feedback indicated that no sites experienced eye, skin, or respiratory irritation from use of the demonstration portable on-demand HOCl disinfectant cleaner.
• Feedback indicated that no sites experienced asthma or allergic reactions from use of the demonstration portable on-demand HOCl disinfectant cleaner.
• Feedback indicated that no sites experienced other negative health impacts from use of the demonstration portable on-demand HOCl disinfectant cleaner.
• Feedback indicated that user physical response to use of the demonstration portable on-demand HOCl disinfectant was comparable to or better than that of baseline products. No significant issues were reported.
• The Project Team performed a cost analysis of the portable on-demand HOCl disinfectant cleaner compared to the demonstration site baseline cleaning products. The demonstration product is cost effective in comparison to baseline ready-to-use cleaning products. This is especially the case when sites purchase their products in unit sizes smaller than a gallon. The price differential per gallon for such baseline products compared to the demonstration HOCl disinfectant cleaner (to include shipping cost) ranged from +$0.94 to +$377.34, with a median price differential range of +$50.08 to +$107.50. Values are stated in ranges due to multiple supply sources and therefore multiple price points identified. In terms of a break-even point that factors in the cost of the Force of Nature electronic device, this ranged from ‘not applicable’ (i.e., the price differential was more than the cost of the device and a gallon of solution) to 158.7 gallons of solution used, being most commonly between 3 gallons to 40 gallons used. The break-even point is here expressed in gallons of use since sites use disinfectants and cleaners at different rates and stating the cost differential by volume of use allows each site to determine the length of time in which their costs would break even.
• It is more difficult to compare the cost effectiveness of disposable wipe products to the demonstration product since the former has no readily quantifiable volume of solution per sheet. The number of wipes that are cost equivalent to a gallon of the demonstration disinfectant solution range from 113 to 376. Again, given the range of prices identified for baseline products, the number of wipes is stated as a range.
• The one area for which the cost effectiveness of the demonstration technology could not be established is large use volume institutional settings that utilize highly concentrated and relatively low-priced disinfectant cleaner products. Users of such products tend to be large healthcare systems or large athletic centers. The baseline cost for one site was initially more expensive due to the cost of the dilution control system utilized, but after 40 gallons of use achieved a cost savings of over $7 per gallon compared to the demonstration product. Two other sites had a baseline cost savings of $7 to $10 per gallon compared to the demonstration product, though the demonstration product may present a cost savings compared to the wipe variant of one of the baseline products. The demonstration product, however, may still offer a cost savings at such locations if it can suitably replace multiple cleaning products. Where that is not the case, the decision to utilize the demonstration technology at such sites would not be driven by cost savings but rather whether the additional health, safety, and other benefits warrant the added cost. In addition, other higher volume hypochlorous acid generation technologies (cart- or wall-mounted) may be capable of achieving a similar or lower life cycle cost as these baseline high-concentration low-cost products. That would ultimately depend on the cost of the device and the cost of salt, vinegar, and water (i.e., the inputs from which the solution is made). Such devices would lack the portability of the demonstration technology and may lack FIFRA registration, making them ineligible for use at federal facilities.

Following initial demonstration of the technology, EPA approved test results validating a product dwell/kill time of two minutes, thereby addressing concerns regarding the previously approved 10-minute dwell/kill time being too long. The product label and efficacy claim document have been updated to reflect the 2-minute dwell/kill time. In addition, the DoD STED Program worked with DHA and the manufacturer to identify and complete other necessary revisions to the product efficacy claim document in advance of technology demonstration at Military Service morale, welfare, and recreation (MWR) facilities. The STED Program will coordinate with DHA and MWR personnel at installations for demonstration of the technology in MWR facilities.