On board a ship, identifying a machine is not the same problem as in a factory. Painted markings fade, maker's plates disappear under paint or rust, and the officer who knew the installation inside out signs off at the end of his contract. QR code and barcode tagging answers exactly that: giving every piece of equipment and every spare a stable identity, readable by anyone, including an engineer joining the vessel for the first time.
Two formats coexist. The QR code, in two dimensions, carries enough information to point to an item's full record in the CMMS. The linear barcode is enough to identify a spare part reference in a store bin. But the real work lies elsewhere: in the label material, in what you encode on it, and in whether the scan works without a network.
Shipboard conditions destroy ordinary labels
This is the first obstacle, and the one most often underestimated. A label printed in the office and laminated lasts a few weeks in an engine room, then peels, yellows, and the code becomes unreadable to a phone camera.
What attacks a label on board
The engine room combines permanently high temperatures, continuous vibration that works on adhesives, and an atmosphere loaded with hydrocarbons. Diesel oil, lubricating oil and cleaning solvents dissolve unprotected inks, and high-pressure washing lifts a poorly fixed label in a single pass.
On deck, salt spray and ultraviolet radiation do the job. Salt creeps under the edges of the adhesive and attacks the substrate. UV fades the print until the contrast between dark modules and light background disappears, which is precisely what the camera needs in order to decode. In tanks and damp compartments, condensation settles under the film and lifts it from underneath.
An unreadable label discredits the whole project
If, six months after fitting, part of the labelling no longer scans, the crew stops trying and the marking becomes decoration. Yet the price of a label is marginal against the cost of the tagging campaign itself, which consumes crew time during a port call or a passage. So you choose the material for the life of the equipment, not for the unit price.
Choosing material and fixing by area of the vessel
There is no universal material: you divide the ship into areas and settle on a marking type and a fixing method for each one.
Engrave or print on a technical substrate
For items exposed to heat and hydrocarbons, an engraved or laser-marked metal plate remains the most durable answer: the code is part of the material, so it can neither fade nor peel. For everything else, a polyester or industrial polycarbonate label with an overlaminated print is a reasonable compromise. Laminated paper only belongs inside a dry, enclosed store.
The fixing matters as much as the material. A high-performance adhesive applied to a degreased, dry surface holds well. As soon as there is heavy vibration, running water or high-pressure washing, mechanical fixing with rivets or screws on a small metal plate is far safer. Where neither suits, a plate mounted on the frame rather than on the hot body of the machine solves most cases.
| Area of the vessel | Dominant constraints | Marking type | Recommended fixing |
|---|---|---|---|
| Engine room and technical spaces | Heat, permanent vibration, oils and diesel, high-pressure washing | Engraved metal plate or overlaminated polyester | Rivets or screws on the frame; high-performance adhesive only outside hot zones |
| Exposed decks and superstructure | Salt spray, ultraviolet, humidity, impact | Engraved metal plate or industrial polycarbonate | Mechanical fixing preferred; adhesive only in sheltered positions |
| Tanks, ballast spaces and damp compartments | Permanent condensation, running water, corrosion | Engraved metal plate | Rivets or screws; never adhesive alone |
| Spare parts store and dry spaces | Frequent handling, bins rubbing together | Polyester; laminated paper acceptable on bins | Standard adhesive or clip-on bin label holder |
| Portable safety equipment | Handling, periodic checks, possible outdoor exposure | Polyester or engraved tag | Cable tie or reinforced adhesive, clear of operating parts |
Position decides whether it gets used
A perfect label in the wrong place is useless. It must sit at eye level or within arm's reach, scannable without a ladder or contortion, and readable without dismantling anything: under a cover or behind lagging, nobody will scan it. It must also sit clear of running water, rubbing and walkways. On large items reached from several sides, two identical labels save a walk around.
The 2D QR code on shipboard equipment
A QR code stores enough data to identify one specific item unambiguously, even when the vessel has several identical machines. That is what makes it the right tool for equipment tracked in the CMMS.
Crew rotation is the real benefit
This is the main argument, and it is specific to shipping. Ashore, a maintenance team stays on the same site for years and ends up knowing the machinery. On board, a second engineer joins for a few months, takes over an installation he is discovering, then signs off. The knowledge leaves with his predecessor, and the handover alongside is far too short to pass everything on.
An officer joining for the first time who scans an item immediately gets what his predecessor carried in his head: the equipment record, its serial number and position, the dated job history, the compatible spares and where they sit in the store, and the maker's documentation. He does not wait for the chief engineer to find out whether the pump in front of him has already been opened this year. This is what makes shipboard knowledge independent of the people who created it.
History, spares and documentation in one scan
Access to history changes the nature of diagnosis. Seeing that the same bearing has been replaced twice in eighteen months points to a misalignment rather than to normal wear, and the date of the last strip-down avoids repeating work the previous team has already done.
The link to spares is just as useful: from the equipment record, the officer knows which references fit, how many remain on board and which bin they are in. This is where equipment tracking meets spare parts management on long voyages.
Reporting a defect where you find it
Scanning also serves to raise the job request at the machine itself. A crew member finds a leak, scans the label, describes what he sees and attaches a photograph. The request lands in the CMMS attached to the correct equipment, with no re-keying and no risk of confusing two identical auxiliaries. It is this accuracy of attribution that keeps the history usable years later. The Equipment module is built on that logic: every item carries a unique identifier to which tasks, counters, jobs and documents are attached.
The 1D barcode in the spare parts store
For parts, the need is different. You are not opening a rich record: you want to identify a reference quickly and record a movement. The linear barcode, readable by hand scanner or camera, is enough and remains the simplest format to produce.
Tag bins and locations, not only parts
Tagging every individual part is often unrealistic: seals, fasteners and small consumables arrive in bags. Tagging bins and locations, by contrast, is immediate and delivers the essentials. The code identifies the location, the location carries the reference, and scanning a bin lets you issue a quantity, count, or check that you are standing in front of the right item. This physical addressing also settles the case of a store reorganised by a previous crew: the CMMS knows the real position, without anyone having to remember the layout chosen three rotations earlier.
Issues and stocktaking
When a part is taken for a job, the scan links the issue to the work order and reduces the stock at the moment of the action, not in the office that evening. It is this gap that creates ghost stock: a reference present in the system and missing from the shelf, discovered at sea, when replenishment takes several weeks and a port call.
Stocktaking follows the same logic: walking the store scanning bins and entering the counted quantity replaces the paper list and the re-keying that follows, and discrepancies are corrected on the spot. The Stock module also allows this data to be handled by file, which is convenient for a full count during a dry-docking.
Safety equipment with expiry dates
Beyond machinery and spares, one family of assets makes tagging pay immediately: everything that carries a date. Extinguishers, liferafts, lifejackets, breathing apparatus, portable gas detectors, air cylinders: each has a periodic check, a service or an expiry date.
That information too often lives in a binder or a spreadsheet kept by one person. By fitting a label to each device and attaching the due date to its identifier, the check becomes verifiable in one scan: date of the last inspection, next due date, associated certificate. A round then consists of moving from one device to the next, scanning, and the list of what falls due builds itself instead of being copied out every month.
The gain is clearest during inspections: when an inspector asks to see an extinguisher at random, nobody searches a binder, you scan it in front of him. Certificate and due date tracking becomes field data rather than paperwork kept to one side.
What to encode: an internal identifier rather than a URL
The question looks technical; it is in fact structural. A mistake here means redoing the entire tagging campaign, label by label.
The problem with a URL
Encoding the web address of the record is tempting: the scan opens the page directly in a browser. But that address is fragile. It changes if you change software, if the vendor alters its address structure, if the vessel is sold or changes manager. On that day, every plate fitted on board points to a page that no longer exists, and you have to visit each item again. A URL also assumes a browser and, more often than not, a connection.
The stable internal identifier
Encoding an identifier that belongs to the fleet, short and without decoration, is the durable answer. The maintenance application recognises it and displays the matching record, whatever software sits behind. If the tool changes, you map the existing identifiers into the new system and the labels remain valid.
A few principles make that identifier robust. It must be unique across the fleet and not only on one ship, so that it still works if equipment is transferred between vessels. It must not encode anything liable to change: putting the position or the department into the identifier guarantees it will be wrong the day the item is moved. It must stay readable in plain text under the code, so it can be copied by hand if the label is damaged. And it must never be reissued, otherwise the histories of two items eventually merge.
Scanning has to work without a link
This is the constraint that rules out most solutions designed for shore industry.
There is no network at the bottom of the engine room
A satellite link does not pass through a steel hull. In a tank, in a lower machinery space, behind several bulkheads, there is neither mobile network nor internal coverage. A tool that needs a server request to display a record does not work where the work is done.
The practical consequence is simple: the data must be on the device. The application holds the equipment database, the history and the documents, the scan resolves the identifier locally, and entries made offline synchronise when the link returns. That is what allows work to continue throughout a passage.
The scan as evidence in front of an inspector
During a visit, an internal audit or a classification society surveyor's attendance, the question is almost always the same: show me what has been done on this equipment. Scanning the item in front of the inspector and producing the dated job history, the parts fitted and the associated documents provides immediate evidence, attached to the physical object in front of him.
This is what chapters 10 and 11 of the ISM Code are aimed at: maintenance of the ship and its equipment carried out to an established plan, with records kept and verifiable. Tagging does not create compliance, but it makes the demonstration direct instead of dependent on a binder, as set out in our article on the ISM Code and the CMMS.
QR code or barcode: what to choose and for what
The two formats are not competitors: they cover two distinct needs on board.
| Criterion | QR code (2D) | Barcode (1D) |
|---|---|---|
| Data capacity | High: several hundred characters | Low: a few dozen characters |
| Main use on board | Equipment and items tracked in maintenance | Spare part references, store bins and locations |
| What the scan opens | Equipment record, history, spares, documentation, job creation | Item identification, stock movement, stocktaking |
| Reading | Phone or tablet camera, any orientation | Laser scanner or camera, orientation matters |
| Tolerance to damage | Built-in error correction: still readable when partly degraded | One scratch across the bars prevents reading |
| Space needed on the object | Compact square, fits a small flat surface | Elongated strip, needs length |
| Typical shipboard material | Engraved plate or overlaminated polyester | Polyester or laminated paper on bins, in dry spaces |
| Works offline | Yes, if the code holds an internal identifier, not a URL | Yes, reading is local by nature |
| Implementation cost | Low for the code, real for a durable material | Very low, ordinary printing |
In practice a ship uses both formats. What they share is the identifier: a single reference list must feed both, otherwise two parallel inventories diverge within months.
Rolling out tagging without disrupting operations
The prerequisite is the reference list: the equipment register must be clean before anything is printed, because tagging a badly inventoried plant means engraving the errors into metal. Fitting then proceeds area by area and port call by port call, starting with critical engine room items, then safety equipment with due dates, then the store. One space fully tagged is worth more than three spaces half done. An inspection after a few months tells you everything about the quality of the material choices and lets you correct the specification for the next vessels.
What tagging really changes on board
QR code and barcode tagging attaches information to the object, so that it no longer depends on the memory of whoever happens to be on board this month. An item that carries its identifier is an item whose history can be found, whose spares can be located and whose due dates can be checked, by any officer, including on the day he joins.
Success comes down to three decisions taken at the start: a material chosen for the area it will sit in, a stable internal identifier rather than a web address, and a scan that works without a network. The rest is execution. To see how these principles translate into a CMMS designed for the vessel, get in touch with the Smart Sailors team.
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