About claims on this page
This page explains how the technology works. EcoloxTech generators are regulated by the EPA as devices, are not registered disinfectants, and we make no efficacy claims for them or for the solution they produce. The only EcoloxTech product with disinfection claims is HOCl-AS200 (EPA Reg. No. 101112-1), and those claims are the ones on its accepted label. Research referred to here describes published studies of hypochlorous acid and electrolysed water under their own test conditions; it is not a claim for any product.
The chemistry of hypochlorous acid
Hypochlorous acid (HOCl) is a weak acid formed when chlorine dissolves in water. It is not an exotic compound: it is the oxidising agent your own neutrophils synthesise inside the phagosome. Evolution arrived at it because it is fast, broadly reactive, and breaks down into innocuous products.
When chlorine enters water it hydrolyses:
Cl₂ + H₂O ⇌ HOCl + HCl
The hypochlorous acid then partially dissociates, and this second equilibrium is the one that matters commercially:
HOCl ⇌ H⁺ + OCl⁻
Both HOCl and OCl− register as “free available chlorine” on a standard test. Chemically they are not the same species, and that distinction is what the rest of this page is about.
Why pH decides the speciation
The position of that dissociation equilibrium is set by pH, and it moves sharply across the range of interest.
| pH | HOCl | OCl− | What that means in practice |
|---|---|---|---|
| 5.0 | ~99% | ~1% | Almost all the free chlorine is the undissociated molecule; our lower control bound |
| 6.0 | ~97% | ~3% | Typical EcoloxTech operating point |
| 6.5 | ~90% | ~10% | Our upper control bound; still strongly HOCl-dominant |
| 7.5 | ~50% | ~50% | The free chlorine is split evenly between the two species |
| 8.5 | ~10% | ~90% | Typical dilute bleach; almost all hypochlorite ion |
| 11+ | <1% | >99% | Concentrated bleach |
Why the two species behave differently is structural. A bacterial cell membrane is a lipid bilayer with a net negative surface charge. The uncharged HOCl molecule crosses it readily; the negatively charged hypochlorite ion is repelled. Published work comparing the two species at equal available chlorine reports substantially greater activity for the undissociated acid, and the research hub collects those studies with their own test conditions, organisms and endpoints.
This is why our systems are controlled to hold pH between 5.0 and 6.5: it is a specification about what the machine produces, which is a statement we can make, rather than a statement about what the solution will do to any particular organism, which is not.
Inside the electrolytic cell
A dilute brine is pumped between a titanium anode bearing a mixed-metal oxide coating — typically iridium-based — and a matching cathode. A low-voltage DC current is applied.
At the anode, chloride is oxidised:
2Cl⁻ → Cl₂ + 2e⁻
At the cathode, water is reduced, releasing hydrogen:
2H₂O + 2e⁻ → H₂↑ + 2OH⁻
The chlorine generated at the anode hydrolyses immediately to hypochlorous acid. The hydrogen is vented safely. Control of current density, flow rate, brine concentration and residence time is what determines the output concentration and, critically, the output pH.
The electrode coating is the engineering heart of the system. Mixed-metal oxide coatings on a titanium substrate resist the aggressive electrochemical environment far longer than bare metals, and their formulation and application are where the difference between a five-year cell and a fifteen-year cell lives.
Single-cell vs. membrane
This is the most consequential specification difference between competing systems, and it is often glossed over in sales material. A longer treatment is on single-cell vs membrane systems.
Single-cell (what we build)
- One chamber; whole flow is usable product
- Output at near-neutral pH 5.0–6.5
- No membrane to foul or replace
- Near-neutral output is more stable in storage than low-pH anolyte
- Generally gentler on stainless steel and aluminium than low-pH anolyte
- Lower cost per usable litre
Membrane (three-cell)
- Ion-exchange membrane splits the flow
- Acidic anolyte at pH 2–3; alkaline catholyte
- Membranes foul and are a recurring cost
- Low-pH output is less stable and more aggressive to materials
- Roughly half the flow is by-product
- Higher true cost per usable litre
Membrane systems are not bad technology — the anolyte they produce is a strong oxidiser, and there are applications where an alkaline catholyte is genuinely useful. For general facility sanitation the near-neutral single-cell approach is easier to store, easier on materials, and cheaper per litre actually used.
Mechanism of action
Hypochlorous acid is a non-specific oxidiser. It does not act on one target: it reacts with membrane lipids, with structural and enzymatic proteins, with sulfhydryl groups in metabolic enzymes, and with nucleic acids. This is why it is chemically unlike an antibiotic, which binds a specific target, and it is the reason oxidising chemistries are usually discussed separately from the acquired-resistance problem. That is a statement about chemistry; it is not a performance claim, and we do not make one.
What the chemistry does not tell you is how long a given task takes. Contact time depends on the organism, the concentration and pH of the solution at the point of use, the temperature, the surface and — more than anything else — how much organic soil is present to consume the oxidiser before it reaches anything living. This is exactly why the regulatory system puts contact times on labels rather than in physics tables.
Where contact times come from
| Source | What it establishes | What it can be used for |
|---|---|---|
| An EPA-accepted label | Organisms, concentration and contact time the registrant has supported with data and the EPA has accepted | The only basis for saying a product kills a named organism. For us that is HOCl-AS200: a five-minute contact time, on the organisms listed on the label, used exactly as the label directs |
| Published research | What happened to a particular organism under the conditions of that study — its concentration, pH, temperature, soil load and method | Understanding the chemistry and designing a programme. It is described as research, with the conditions attached, and it is not transferable to a product as a claim |
| A generator specification | What the machine produces: free available chlorine, pH, output rate | Sizing, set points and verification. It says nothing about organisms, because a device carries no efficacy claims |
| Your own validation | Whether your written procedure achieves your acceptance criteria, in your plant, on your soil | Your food safety plan and your auditor. This is the evidence that actually matters on site |
The practical consequence for a buyer is simple. If a task needs a documented kill claim — because a customer, a scheme or a regulator requires one — use a registered product according to its label. If a task does not, generated solution is chosen on chemistry, cost and handling, and verified on your site with your own data. Understanding contact times sets this out in full, including the complete HOCl-AS200 label table, and the research hub holds the studies.
Anyone who shows you a table of organisms and seconds attached to a generator is telling you something the regulatory system does not permit them to tell you. It is worth asking where the numbers came from.
Stability, storage and decay
Hypochlorous acid decays. Understanding how is what makes onsite generation compelling rather than merely convenient.
Three factors drive the decay: light, particularly UV, which photolyses the molecule; heat, which accelerates every reaction pathway; and pH drift, which shifts the equilibrium toward hypochlorite ion. Dissolved organic material and metal ions also consume it.
Stored properly — sealed, opaque, cool, out of direct sun — generated solution holds its free available chlorine for days to weeks with gradual decline. Stored badly, in a clear bottle on a sunny windowsill, it can lose most of its free chlorine in days. Measure it rather than assuming it: strength at the point of use is the number your procedure depends on.
Our ultra-pure bottled product for cosmetic and pharmaceutical applications is a different case: produced from RO/DI water with pharmaceutical-grade inputs and optionally sealed under a nitrogen blanket, it carries room-temperature chlorine-retention data over 24 months without preservatives.
The operational point
A generator makes the storage question mostly irrelevant. If a fresh batch is five minutes away, nobody is depending on a drum of unknown age to hold its concentration.
Feedwater and pre-treatment
Feedwater quality is the most common cause of disappointing generator performance, and it is almost always solvable.
- Hardness is the primary enemy. Calcium and magnesium precipitate onto the cathode as scale, which reduces efficiency, distorts output concentration and shortens electrode life. Softening ahead of the cell is standard on commercial installations.
- Iron and manganese stain and foul, and consume active chlorine directly.
- Organic content consumes oxidiser before it ever reaches your surfaces.
- Salt quality matters more than people expect. Food-grade, non-iodised salt without anti-caking agents; the additives in table salt foul cells.
Where the output is destined for cosmetic or ophthalmic formulation, the standard rises to double-filtered RO/DI water and USP-grade, heavy-metal-free sodium chloride.
Safety, handling and SDS
Handling information comes from the safety data sheet for the product in front of you, not from the category. The SDS for HOCl-AS200 (Rev 07, 15 August 2025) classifies it as not a hazardous substance or mixture, lists no ingredients hazardous at the levels present, and states that eye protection is not required for normal use, with safety glasses if desired. We recommend splash goggles as ordinary good practice, which is more conservative than the sheet requires. The label directs that any secondary container be white HDPE, and the product is not a sterilant.
Two things deserve more care than the solution itself. First, the inputs: ready-mixed brine products contain hydrochloric acid and are genuinely hazardous concentrates — gloves, goggles and an apron, per their own SDS. Second, mixing: combining chlorine chemistry with ammonia or acid liberates toxic gas, and that hazard does not disappear because the chlorine came from a generator. Store in opaque closed containers, label secondary containers, ventilate the cell area, and keep the SDSs where the work happens. HOCl safety and SDS covers this in detail.
Our ultra-pure grade for cosmetic and ophthalmic formulation is supplied with its own human repeat insult patch test and cytotoxicity documentation; ask for the current dossier rather than relying on a summary.
What HOCl does not do
Credibility requires saying this plainly.
- It is not a cleaner. It has minimal surfactant action. Soil must be removed mechanically or with a detergent first; HOCl is the step after that, not instead of it.
- It is not equally effective on everything. Bacterial spores are the hard case for every oxidising chemistry, and organic soil changes the arithmetic on any surface. Where a documented result is needed, that is what a registered label and your own validation are for.
- It does not last indefinitely. Anyone claiming a stable, indefinitely potent HOCl solution at ambient conditions is describing something other than what is in the bottle.
- Generated solution is not a registered disinfectant. Where the regulation, the scheme or the customer requires a registered label, use HOCl-AS200 according to its directions.
- It does not fix a bad procedure. Better chemistry applied to unclean surfaces on an inadequate schedule produces the same outcome as worse chemistry did.
Questions
Is electrolysed water the same thing as hypochlorous acid?
Not quite, and the loose usage causes confusion. “Electrolysed water” describes any solution produced by passing current through a brine, which includes strongly acidic anolyte, alkaline catholyte and near-neutral solutions. Hypochlorous acid is the specific molecule. Our systems produce near-neutral electrolysed water in which hypochlorous acid is the dominant chlorine species. Electrolysed water explained sorts out the terminology.
What about biofilm?
Biofilm is a physical problem as much as a microbiological one: the extracellular matrix shields the organisms inside it, and any oxidiser is consumed reacting with the matrix before it reaches them. That is why biofilm work is approached with mechanical action, adequate concentration and realistic contact time rather than chemistry alone, and why published biofilm studies use quite different conditions from suspension tests. We do not make biofilm claims for generated solution.
Why does organic soil reduce effectiveness?
Because hypochlorous acid is an oxidiser and it does not discriminate. Protein, fat, sugar and soil consume the active chlorine just as readily as anything else. Oxidiser spent on yesterday’s soil is not available for the task in front of it. Clean first, then sanitise — the sequence is not a formality.
How is concentration measured?
As free available chlorine (FAC) in parts per million, using test strips or a calibrated colorimetric meter. A FAC reading alone is incomplete — record the pH with it, because the same FAC at pH 6 and at pH 9 is a chemically different solution.
Is it corrosive to equipment?
Near-neutral HOCl at use concentration is generally gentler on stainless steel and aluminium than high-strength chlorine, peracetic acid or the low-pH anolyte from membrane systems. Any oxidiser will attack some materials over time, so check compatibility for your specific equipment; the material compatibility list forms part of the installation documentation.
Why does this page not list kill times?
Because kill claims belong to registered products. EcoloxTech generators are EPA devices and carry no efficacy claims, so attaching organisms and seconds to them would be a claim we are not permitted to make. The full HOCl-AS200 label table is on understanding contact times, and the underlying studies are in the research hub.