Hypochlorous Acid Generators

What a HOCl generator is

A hypochlorous acid generator is a piece of equipment that manufactures disinfectant on your premises. It takes two commodity inputs — softened water and food-grade salt — passes them through an electrolytic cell, and delivers a ready-to-use solution of hypochlorous acid at the concentration you specify. There is no drum to receive, no concentrate to dilute, no expiry date on a pallet, and no empty container to dispose of.

The chemistry is not new. Hypochlorous acid is the same compound the human immune system produces inside neutrophils to destroy invading pathogens. What has changed is the cell design and control electronics that make producing it reliably, at a stable pH and concentration, economical at industrial scale.

The practical consequence for a facility is a shift in cost structure. Purchased disinfectant is a recurring operating expense that scales with the size of your operation and rises with every freight surcharge. An onsite generator is a capital item with a consumable cost measured in the price of salt and electricity. For most commercial buyers the crossover point arrives well inside the first two years.

How electrolysis produces HOCl

Brine — sodium chloride in water — is pumped into an electrolytic cell containing a titanium anode coated with a mixed-metal oxide, typically iridium-based, and a matching cathode. A low-voltage direct current is applied across the electrodes.

At the anode, chloride ions give up an electron and form chlorine, which immediately hydrolyses in water to hypochlorous acid. At the cathode, water is reduced, producing hydrogen gas and hydroxide ions. The overall result is a solution containing hypochlorous acid as the dominant active species, along with dissolved hydrogen that is safely vented.

The single most important variable in the output is pH, because pH determines the ratio between hypochlorous acid (HOCl) and the hypochlorite ion (OCl−):

This is the entire argument for near-neutral electrolysed water. A bleach solution and an EcoloxTech output can both report the same free available chlorine, yet perform very differently, because in the bleach almost all of that chlorine is sitting in the less-active ionic form. Our systems are controlled to hold pH between 5.0 and 6.5, which keeps the great majority of the chlorine as HOCl while staying gentle on stainless steel and skin.

Single-cell versus membrane systems

Two architectures dominate the market, and the distinction matters when you are comparing quotes.

Membrane (three-cell) systems separate the anode and cathode chambers with an ion-exchange membrane, producing two streams: an acidic anolyte (the disinfectant, typically pH 2–3) and an alkaline catholyte (a degreaser). They generate a very strong oxidiser, but the low pH is corrosive, the solution is unstable, membranes foul and need replacing, and roughly half the throughput leaves as a by-product you may not want.

Single-cell systems, which EcoloxTech builds, run the full brine stream through one chamber and control the chemistry to land at near-neutral pH. Everything produced is usable disinfectant, there is no membrane to replace, the solution is materially more stable in storage, and it is safe on stainless, aluminium, food-contact surfaces and skin.

Types of generator

Generators fall into four practical categories, distinguished less by chemistry than by how they fit into a facility.

1. Portable and countertop

Battery or USB-powered devices producing a few hundred millilitres per cycle. Appropriate for households, single treatment rooms, small clinics, offices and travel. The EcoloxTech Micro makes 300 ml in five minutes from one gram of salt.

2. Wall-mounted commercial

Plumbed units producing continuously into a tap or a holding tank, sized for a single building or a small line. The EcoloxTech 300 delivers 300 L/hr, which covers most restaurants, schools, dental and medical practices, hotels and small food operations.

3. Industrial skid systems

Floor-standing systems feeding a distribution loop, wash lines, CIP circuits or fogging networks across a plant. The EcoloxTech 1200 produces 1,200 L/hr and is the workhorse for food processing, poultry, seafood, produce packing and shipboard installation.

4. Application equipment

The generator makes the solution; something has to apply it. Electrostatic sprayers such as the Jet H2 charge the droplets so they wrap around three-dimensional surfaces instead of only coating what faces the nozzle, which materially improves coverage per litre.

Capacities and sizing

Sizing is a demand question, not a floor-area question. Work through it in this order:

1. Total daily volume. Add up every application: surface sanitation, wash water make-up, CIP charges, fogging cycles, footbaths, drain treatment.
2. Peak hourly draw. Identify the worst hour of the day, usually shift changeover or end-of-day wash-down.
3. Buffer capacity. A holding tank lets a smaller continuous generator serve a larger intermittent peak. This is almost always cheaper than buying a bigger generator.
4. Growth headroom. Add the second line, the extra shift, or the sister site you are already planning.

How to choose

Six questions decide the specification. If you can answer these, you can be quoted accurately.

What concentration does your application need?

Food-contact surface sanitation typically runs 50–200 ppm. Produce and protein wash water is commonly 50–100 ppm. Fogging and general disinfection sit around 100–200 ppm. Heavy organic-load environments and drain or biofilm work justify 200–500 ppm. Our commercial systems are adjustable across that whole range, so one machine covers several protocols.

Continuous or batch?

A line that runs eight hours wants continuous production straight into the process. A facility that cleans twice a day wants batch production into a tank overnight, at a lower equipment cost.

What is your feedwater like?

Hardness scales electrodes and shortens service intervals. Almost every commercial installation should include softening; sites producing cosmetic-grade output use RO/DI. Get a water report before you get a quote — it is the single most common cause of a revised proposal.

How will it be applied?

Spray bottles, hose stations, foamers, electrostatic foggers, dosing into a wash tank, injection into a CIP loop, or plumbed to a water line. The application method determines the distribution design, and sometimes the generator size.

Do you need a registered label?

This is the question most buyers discover late. Onsite-generated HOCl is used as a cleaner and sanitiser. If your protocol, insurer or auditor requires an EPA-registered disinfectant with specific public-health claims, you need a registered product — our HOCl-AS200, EPA Reg. No. 101112-1. Many sites run both: generated solution for volume cleaning and sanitising, registered product where the claim must be on a label.

Buy, finance, or lease?

Small units are bought outright online. Custom systems are typically ordered on a 50/50 deposit — half to begin the build, half before shipment. Our commercial leasing programme spreads the cost over 24 months and refurbishes or replaces the unit at renewal, which suits operators who prefer the equipment to sit in opex.

Full system comparison

Technical specifications

Applications

One generator, one chemistry, and a long list of jobs it can legitimately do:

• Hard-surface sanitation — benches, tables, equipment exteriors, contact points, restrooms.
• Food-contact surfaces — within the 200 ppm limit, generally without a potable rinse.
• Produce and protein wash — dosed into wash water to reduce cross-contamination and extend shelf life.
• Clean-in-place — as the sanitising step in a CIP circuit, without the corrosion cost of stronger oxidisers.
• Fogging and space treatment — particularly with electrostatic application in cold rooms, processing halls and vehicles.
• Ice machines, drains and biofilm — where recurring contamination originates.
• Water lines and irrigation — controlled dosing within potable limits.
• Footbaths and boot washes — zone-transition control in processing and livestock facilities.
• Hand and skin contact — non-irritating at use concentration, unlike quats or peracetic acid.

See how these combine in your sector on the industry programme pages.

HOCl vs. other chemistries

The honest caveat: HOCl is not a universal solvent for every sanitation problem. Heavy soil must still be removed mechanically first — oxidiser consumed by organic load is not available to kill anything. Bacterial spores need longer contact times than vegetative cells. And generated solution is not a substitute for a registered label where a registered label is what the rule requires.

ROI and payback

The model is straightforward. Replace a per-litre purchase price with a per-litre production cost, and set the difference against the equipment.

The production cost of onsite HOCl has three components: salt, electricity and water. All three are commodity inputs, and together they typically land in the low cents per litre. Purchased ready-to-use disinfectant, by contrast, carries the manufacturer’s margin, the packaging, the freight, and increasingly a fuel surcharge.

What buyers consistently underestimate are the second-order savings:

• Storage space released from a chemical store, often in a building where floor area is expensive.
• Handling and administration — ordering, receiving, stock rotation, decanting, disposal of containers.
• PPE and training for hazardous chemical handling that is no longer needed at the same level.
• Dilution error, which quietly costs money in two directions: over-dilution that fails an audit, and over-concentration that wastes product and damages equipment.
• Downtime from corrosion, and from contamination events that a more consistent protocol would have prevented.

Installation and commissioning

A commercial installation follows the same sequence every time.

1. Site survey. Feedwater analysis, power availability, drainage, mounting location, and a map of the draw points the system will serve.
2. System design. Generator size, buffer tank volume, pump and distribution layout, control and interlock strategy.
3. Pre-treatment. Softening — or RO/DI where output purity demands it — installed ahead of the cell.
4. Mechanical installation. Mounting, plumbing to feedwater and drain, power connection, distribution pipework to the draw points.
5. Commissioning. Calibration of concentration and pH, verification against test strips and meter, flow and pressure checks across the distribution network.
6. Validation. Baseline environmental swabs, then post-implementation swabs, so the change is documented rather than assumed.
7. Training and SOP. Written procedures for operators, QA and maintenance, in a form your auditor will accept.

Lead time on a commercial system is confirmed at quotation. The 50/50 deposit structure means the build starts on receipt of the first half and ships on the second.

Maintenance and consumables

There is not much to it, which is the point.

Regulatory position

Three distinctions do most of the work here, and confusing them is the source of nearly every compliance argument we see.

Sanitiser versus disinfectant. These are regulated claims with defined efficacy thresholds, not synonyms. What you may legally claim depends on the product and its registration, not on the chemistry alone.

Generated solution versus registered product. Onsite-generated HOCl is used for cleaning and sanitising. HOCl-AS200 is an EPA-registered disinfectant, Reg. No. 101112-1, and carries specific public-health claims on its label. Where the rule, the auditor or the insurer requires a registered product, use the registered product.

Food-contact limits. Hypochlorous acid on food-contact surfaces is permitted up to 200 ppm total available chlorine when ready for use; potable water applications are limited to 4 mg/L. Both figures are worth knowing before you set a protocol.

Full citations, label documents and downloadable compliance material are on the regulations page.

Frequently asked questions