Ashore, a chemistry is chosen on performance and price. At sea it is chosen on whether you can carry it, stow it, hand it to a rotating crew and use it in an occupied public room at eleven at night. This page compares onsite-generated hypochlorous acid with what vessels actually run, on the axes that decide it aboard. Efficacy against named organisms belongs to each registered product’s label and is deliberately not the axis here.
About claims on this page
EcoloxTech generators produce a hypochlorous acid solution on site. They 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), used according to its label. Research cited here describes published studies of hypochlorous acid and electrolysed water under their own test conditions; it is not a claim for any product.
At a glance
| Chemistry | Form aboard | Safety and PPE | Life at sea |
|---|---|---|---|
| Hypochlorous acid (generated or RTU) | Dilute solution at use strength, pH 5.0–6.5 | Splash goggles recommended; no gloves or respirator required for normal use per the HOCl-AS200 SDS. Never mix with acids or ammonia | Made aboard from salt, water and power. No concentrate to stow. Decays, so it is made rather than hoarded |
| Sodium hypochlorite (bleach) | Corrosive concentrate, diluted by crew | Goggles or face shield, chemical-resistant gloves and apron; eyewash; ventilation | Cheap and familiar, but stowage, segregation and spill exposure in a moving vessel, plus odour in enclosed spaces |
| Quaternary ammonium | Concentrate, diluted by crew | Concentrates can cause serious eye damage and skin burns: goggles and gloves while diluting | Compact to carry and leaves a residual film, but food-contact use constrained and binds to some cloths |
| Hydrogen peroxide / AHP | Concentrate or ready-to-use | Concentrates are strong oxidisers: goggles or face shield, gloves, protective clothing | RTU formats are convenient aboard; every bottle is still carried, stored and disposed of |
| Peracetic acid | Corrosive, pungent oxidising concentrate | Goggles and face shield, gloves, apron, ventilation and respiratory protection where vapour may exceed limits | Rarely suitable outside technical or galley plant areas; odour is unacceptable in passenger spaces |
| Alcohol-based products | Flammable liquid | Flammable-goods stowage and handling | Fire risk is the governing constraint aboard; quantity limits apply |
| Hot water and steam | Utility | Burn and scald risk | Useful where equipment tolerates it; adds heat and moisture in spaces that already have both |
The constraint nobody ashore thinks about: stowage
Every drum of concentrate aboard is a managed item. It occupies space that competes with provisions and revenue, it has stowage and segregation obligations, it needs spill controls that work on a moving deck, and it has to be tracked. A ship also cannot take a mid-voyage delivery, so quantities are set by the longest itinerary rather than by average use — which means carrying for the worst case all year.
Onsite generation replaces that with salt, water and power. Salt is inert, cheap, stowable anywhere and not a hazardous good. This is the single largest practical difference between the options above, and it is usually worth more to a vessel operator than the chemical saving.
Odour and use in occupied spaces
A cruise ship cleans in front of guests, continuously, in enclosed spaces with finite air changes. That rules a lot in and out before efficacy is discussed. Peracetic acid is not usable in an atrium. Bleach at working dilution is noticeable in a stairwell and unmistakable in a cabin bathroom. A near-neutral solution at use strength is typically far milder, which is why it suits a high-frequency routine in public areas — ventilation requirements still follow the product label and the ship’s risk assessment.
Crew, rotation and training
Any chemistry aboard has to be safe in the hands of a crew that turns over. Concentrates mean dilution stations, PPE compliance and training repeated at every crew change; a solution delivered at use strength removes the dilution step entirely, which removes both a hazard and a source of variability. The wider comparison of handling and PPE across chemistries is on HOCl vs other sanitation chemicals.
Materials in a marine environment
Ships combine stainless, aluminium, coated steel, brass fittings, soft furnishings and a permanently saline atmosphere. Any oxidiser will affect some materials over time, and near-neutral solution is generally gentler on stainless and aluminium than high-strength chlorine or low-pH anolyte. Check compatibility for the specific surfaces — balcony fittings, gym equipment and galley alloys are the usual questions — and add a wipe or rinse step where prolonged contact is likely.
The cost model aboard
| Carried concentrate | Generated aboard | |
|---|---|---|
| What you pay for | Every litre, plus freight to the port and handling at the quay | The system once; salt, water, power, filters and service ongoing |
| Stowage | Managed hazardous-goods space, sized for the longest itinerary | Salt and, if used, a holding tank |
| Logistics | Bunkering schedules tied to ports and agents | None, beyond salt |
| Crew labour | Receiving, striking down, stock control, dilution | Refills, testing, periodic service |
| Outbreak response | Consumption spikes against a fixed quantity aboard | Consumption spikes against a production rate |
| Fleet effect | Multiplied across hulls, with per-port price variation | Multiplied across hulls, with standardised procedures |
The fleet numbers, including a real example, are on the fleet ROI page.
Where the incumbent still wins
- Medical and clinical protocols that specify a registered product. Use what the protocol names.
- Tasks needing residual activity. Hypochlorous acid leaves none.
- Water-system treatment, which is plant chemistry under the ship’s water-management plan and the VSP Standards, not a housekeeping choice.
- Specific technical applications already validated around another chemistry.
- Heavy soil. That is a detergent problem in every programme.
Designing the programme, not choosing a product
A vessel typically ends with something like this: detergents unchanged; generated hypochlorous acid for galley surfaces, buffets, high-touch public areas, toilets, cabins and crew accommodation; a registered product where the medical centre or a written protocol specifies one; alcohol-based hand products at hygiene stations under their own controls; hot water where equipment allows; and water systems managed entirely separately as plant.
That is a programme, and it is much easier to defend at inspection than a single-product story. Write down why each chemistry sits where it does, because crew change and the reasoning has to outlast the person who made the decision.
Questions worth asking any supplier
- What does this actually cost delivered to the ship, per port, including freight and agency handling?
- What stowage and segregation does it require, and how much space is that?
- What happens to our programme if a port call is missed?
- Is it usable in occupied public spaces, and what does the label say about ventilation?
- What PPE does a rotating crew need, and what does training at every crew change cost?
- Which claims are on the label, and which of them are we relying on in our protocol?
- Is the guidance you are quoting from the 2025 VSP Standards or the superseded 2018 manual?
The one thing no surface product replaces
Norovirus moves on hands. Every comparison above is about surfaces, and none of it substitutes for hand hygiene at the gangway, outside every restaurant, at the buffet entrance and in crew areas — with dispensers that are stocked, sited where people actually walk, and used under supervision rather than passed.
Hand products are a separate regulatory category with their own rules, and this is not an argument for applying a surface sanitiser to skin. The hub does hold in-vitro work on hypochlorous acid as a skin antiseptic, hypochlorous acid as an alternative skin antiseptic, an in vitro comparison, cited as research; it is not a recommendation for shipboard hand hygiene, and the products at your stations should be the ones chosen for that purpose. Where generated solution helps is by freeing budget and attention: when the surface programme stops being rationed, the argument about what to spend on hand-hygiene stations gets easier.
Frequently asked questions
Is this cheaper than bleach?
Per litre, bleach is hard to beat. Aboard, the comparison is stowage, handling, logistics and outbreak response, and that is where generation wins or loses. Run it on your own numbers.
Can we stop carrying concentrate entirely?
Usually not entirely — medical protocols and some technical applications keep their own products. Most of the housekeeping and galley volume can move.
Does it smell in cabins and public rooms?
At use strength it is typically far milder than bleach or peracetic acid at working dilution, which is why it suits high-frequency work in occupied spaces. Follow the label and your risk assessment on ventilation.
What about our aluminium and brass fittings?
Check compatibility for the specific materials and add a wipe or rinse where contact is prolonged. Near-neutral is generally gentler than high-strength chlorine, but no oxidiser is inert.
Is salt really a non-issue to store?
It is inert, cheap and not a hazardous good. It still needs dry stowage and it is heavy, so include it in the survey rather than assuming it disappears.