Why a deck is not one surface
Ask for the deck as a material list before anyone quotes a method. On most vessels the walking areas mix at least four things that respond very differently to heat and to water: teak or another timber, a moulded non-skid coating, gelcoat on hatches and coamings, and sealant bedding compound along joints, portlights, stanchion bases and deck fittings. Add stainless hardware, anodised or painted superstructure, rub rails, and anything vinyl or decalled, and a single instruction to steam the deck stops meaning anything.
The practical consequence is that the check list has to be written per surface, not per vessel. One deck may need a dry pass over the non-skid tread, nothing at all over old sealant edges, and a plain water rinse on the timber. Write the surface list first, then decide the method row by row. Any supplier answer that treats the deck as one line is not an answer you can act on.
Check the deposit before checking the machine
Deck soil is layered, and the layer that is hardest to see is often the one that decides the method. Salt film and dried spray are mineral and behave nothing like grease. Organic growth such as algae or mildew in a shaded berth is soft but holds water inside the surface. Oil and diesel film from stern gear or a leaked tankage spreads. Black streaking from rubber dust at a toe rail is a different problem again. Then there is whatever was used last season, which may already have sealed dirt into the tread of the non-skid.
A steam process is a strong candidate for the greasy and organic layers because it works on heat and dwell rather than on scrubbing force, and it puts far less water on board than a hose. It is a weak candidate for a loose salt film, which needs a rinse, and it is the wrong answer for anything that has to come off mechanically. Type the deposits in writing, in the order they sit on the surface, and state which one the trial has to remove. That single sheet is what turns an argument about equipment into a question about a job.
Check where the machine stands and where its services come from
The reach of the equipment is decided long before the lance moves. A fixed unit sits on a quay or in a workshop. A mobile mobile steam cleaning machine has to get from a vehicle to the pontoon, over a finger, down a step and along a swinging berth without dragging its own supply lines through the obstacle course of cleats, stanchions and lines that a deck actually is. Draw the walking route on the marina plan and mark the pinch points.
Then answer four questions in writing for the exact unit being quoted: what power is available at that berth and who owns it; what water the machine will actually be fed with; how far the hose and supply have to run, and what happens to reach and to the operator's freedom of movement as that distance grows; and how long the machine can work before it stops for a refill or a charge. Read that last one carefully, because a tank figure on a data sheet is a tank figure and not a working time, and a boatyard afternoon is not a laboratory cycle. PowerDe's published cleaning pages describe the mobile range for indoor garage bays and narrow outdoor parking spaces, and the fixed machine for vehicle exterior, interior and engine-compartment work. Marine or yacht work does not appear on those pages as an application, so nothing about a vessel deck can be taken for granted from a brochure, and everything about the berth has to be established on site.
Check the water going into the machine
Marinas are a poor water environment for equipment. Supply at a pontoon is often hard, occasionally treated, and drawn from a main that is flushed irregularly. Vessel tanks may hold water that has sat for weeks. Salt spray gets into hoses left on deck. Ask, in writing, what feed water the quoted machine is designed for, what connection it uses, and what the site has to provide or adapt in order to deliver that feed at the berth. A machine fed with water it was not designed for shows the cost later in the heater and in its internal passages, and a failure that appears after a season of berth work is rarely a cheap conversation.
Write the exclusions before the first pass, not after the first mistake
There is a list of things on any deck that a heat and steam process should not be pointed at, and that list belongs on the front page of the job sheet. Bedding and caulking that is old, cracked or recently renewed. Timber that is dry, uncoated, greyed or lifting at the edges. Coated non-skid that has already begun to fail. Vinyl, decals, deck graphics and boot topping. Varnished work. Around transducers, anodes, vents and through-deck fittings. Inside chain lockers, and under any hatch that is not secured open. Where a surface cannot be steamed, the job sheet should name what happens instead, whether that is a cold rinse, a brush, a solvent the yard already uses, or nothing at all until the surveyor has looked.
Ask what the supplier's own documentation says about surfaces, dwell and distance, and ask how the protective arrangements behave through a long job. PowerDe's cleaning pages list items such as earth-leakage disconnection, short-circuit and overload disconnection, over-temperature cut-out, live-part protection and low-water-level cut-off on particular listings, but the wording is not identical from page to page. Do not accept a tally of protections as a specification, and do not assume that an arrangement mentioned on one listing applies to another machine or to another variant of the same model.
Run the check on a patch you can afford to lose
Before any of this becomes a deck-wide decision, put the method on a small area where a bad result is an inconvenience rather than a survey finding. On a trailerage or hard-standing job that may be a section of toerail or the underside of a coach roof. Afloat it may be a short run of non-skid at the bow, out of sight. Photograph it before, tape the boundary, run one defined pass, then let it dry and look again in daylight. What you are looking for is not only cleanliness. It is lift at the edge of the tread, colour change, a bloom under a coating, a seam that has opened, and any change in how the surface feels under a wet shoe.
Set the stop conditions on the same sheet before the trial starts. Phrases that work: any lifting of a coating at a taped edge; any colour change that remains after drying; any softening of old sealant; any water finding its way under a fitting. Write who is allowed to call a stop, and accept that the person holding the lance is not the person who signs the result.
Check what you are allowed to put over the side
This is the check most often skipped and the one that costs the most afterwards. Marinas and yards set rules about wash water, and a steam process produces hot, dirty run-off in a small volume rather than the large cold wash a hose generates. That is usually an advantage, but it does not answer the question. Ask the berth holder or yard in writing where the run-off may go, whether any product is permitted at all on their hard standing, whether the deck has to be rinsed afterwards, and who provides containment. Record the answer with a name and a date on the job sheet. Steam puts less water on a boat, which matters where tankage and drying space are limited, but it also leaves the deck hot and damp at the end of a pass, and a wet, slanted deck at closing time is an incident waiting to be written up.
Check the conditions the operator is working in
Steam on a deck means a heat source, a supply of hot water and a trailing hose, used by someone standing on a surface that is wet, angled and full of trip points. Before work, walk the deck for the route the operator will take and clear it: lines, fenders, a hatch cover propped open, a winch handle left in its socket. Agree where the machine stands so that the hose does not cross a walkway. Agree who is on the pontoon and who is on board, because nobody should be below or beside a deck being worked from above. Agree what the operator wears and what the crew are told before the machine starts, not after. Then agree what happens if the deck is still wet at the end of the session, whether that is a set drying time, a rinsed and squeegeed finish, or a decision not to walk the boat until morning.
What to ask a supplier in writing before you commit
Send the surface list and the deposit list, and ask for answers against each row rather than a general comment. Where a supplier points at a machine listing, ask for the specific rows in their own words. PowerDe publishes a specification table for the Fixed Steam Cleaning Machine PowerDe HW02 that gives, among other fields, a working voltage, a heating power, a steam temperature, a vapour pressure, a tank volume and material, an overall footprint and a tap-water inlet arrangement. Those figures belong to that quoted machine, printed on that page. They are not a description of what a mobile unit will do at a berth, and carrying a figure from one page onto a different job is exactly how cleaning damage gets ordered. Ask for the figures of the unit you would actually be sent, and for the rows the page does not print at all: how long it can run, how far the hose reaches, how it is fed, what it weighs and how it moves.
Then ask the questions data sheets never answer. What does the supplier say about coated non-skid, timber and sealant? What dwell and stand-off do they describe, if any? What do they require the operator to do about run-off? What service route applies to a boatyard, where equipment may sit unused for months between seasons and then work hard for one week? If the answer to any of these is that the duty is not one they normally cover, that is useful information rather than a rejection.
Check whether the standard duty fits the vessel at all
Some vessels need something that is not a catalogue item. A large working boat with a long flush deck, a fleet of charter hulls turned around on the same weekend, a yard that wants a fixed point on the quay rather than a machine on a trolley: each of these changes the answer about how equipment is fed, how it moves and how it is maintained. A customized steam cleaning equipment enquiry is where that goes on the record, and it works best when the enquiry already contains the surface list, the berth conditions, the water and power that exist at the position, and the trial result described above. If a vessel deck turns out to sit outside what the published range is positioned for, say so plainly and ask whether anything else in the range would serve. A clear gap saves more money than a hopeful order.
Make the pass finish in a condition you can hand back
A steam pass is not finished when the lance goes down. The deck has to be dry enough to walk on, free of the residues that were loosened, and checked while still warm enough to show a defect. Build the closing rows into the job sheet: the wipe-down or rinse that removes what the heat lifted, the drying time before crew or owners board, the inspection of the taped test area against the before photograph, the containment taken away and disposed of as the berth holder required, and the name of the person who signed off. Then keep the sheet. A repeat job on the same hull is far cheaper when the next crew inherits a surface list, an exclusion list and a trial result instead of a memory.
The checks worth signing
| Check | What the answer has to state |
|---|---|
| Deck material list | One row per material, each with its own method or its own exclusion |
| Deposit type and order | Named layers, with the one the trial must remove marked out |
| Machine position and route | Walking route drawn on the berth plan, pinch points marked |
| Power, water feed and reach | Who supplies what, what connection, how far the hose has to run |
| Exclusion list | On the front page of the sheet, each row with a written alternative |
| Trial patch and stop conditions | Taped area, before photograph, and who may call a stop |
| Run-off permission | Named berth holder, named route, dated on the sheet |
| Figures for the exact unit quoted | From that listing only; unpublished rows recorded as gaps to close |
| Hand-back condition | Dry enough to board, residue removed, sign-off name entered |
Steam is a serious option on a yacht deck precisely because it does the hard part with heat and dwell instead of force and water volume, and that is also why it has to be scoped rather than improvised. Work the checks in the order above, put the answers on paper, trial the method where a mistake is cheap, and keep the sheet. A buyer who does that is comparing methods and results rather than brochures.
