The British Marine Electronics Association code of practice is the industry's own benchmark for how electrical and electronic installations on leisure boats should be carried out. It is not a legal requirement in the way the Boat Safety Scheme is for inland waterways, but it sits behind good practice across the trade and behind the technical standards that insurers and surveyors expect to see followed.
For an owner, the practical question is not the document itself but what it means for the work being done on your boat: which cables, which fuses, which methods, and which checks happen before the installer packs up. This guide sets out what the code covers and how to tell whether a contractor is actually working to it.
The code draws together the relevant ISO standards for small craft electrical systems, principally BS EN ISO 13297 for AC and DC installations and BS EN ISO 10133 for low voltage DC systems, into a single practical reference for installers. It covers cable selection and routing, protection devices, battery installation, earthing and bonding, and documentation.
It is aimed at the people doing the work rather than the boat owner, but it is the document that underpins most of what a competent marine electrician does without necessarily citing chapter and verse. When a surveyor writes that an installation does not meet recognised standards, this is usually the reference point.
ISO 13297 covers the AC and DC electrical systems on small craft generally: circuit protection, conductor sizing, switchgear and labelling. ISO 10133 deals specifically with extra low voltage DC systems, the battery-fed circuits that make up most of a typical boat's wiring, and sets out requirements for cable sizing against current and voltage drop, fusing close to the source, and battery installation including ventilation and securing.
The BMEA code translates these into a practical sequence: how to plan a job, what to check before starting, what to record afterwards. It is common for a boat to have some circuits that comply and others, often added later by a previous owner, that do not. Bringing an installation up to standard rarely means rewiring the whole boat, but it does mean identifying which circuits fall short and addressing those specifically.
Marine insurers do not usually ask for a certificate confirming compliance with a named standard, but a surveyor assessing a boat for insurance or purchase will flag wiring that clearly falls outside recognised practice, undersized cable, domestic consumer units, unprotected circuits, missing bonding. Those findings can affect valuation, insurance terms, or become subjects to a pre-purchase agreement.
Work carried out to the BMEA code, with proper documentation, gives you something concrete to show a surveyor or a future buyer. It also gives you a reference point if a fault develops later, since the installer's records show what was fitted, where, and to what specification.
In practice this shows up as unglamorous but important details: tinned marine-grade cable rather than domestic twin and earth, fuses or breakers sized to the cable rather than the load alone, connections made with proper marine terminals rather than twisted and taped joints, and a written record of what was installed.
It is reasonable to ask a contractor directly whether they work to BMEA guidance and ISO 13297/10133, and to ask for documentation on completion. A competent marine electrician will not be put off by the question.
None of this prevents an owner doing their own electrical work, and plenty of straightforward jobs, fitting a USB socket, adding an interior light on an existing protected circuit, are well within a competent owner's ability. Where it matters more is anything touching the main battery circuits, the AC shore power system, or work that will be relied on for safety, bilge pumps, gas alarms, navigation lights.
If in doubt, get the higher-risk parts of a job done professionally and to a documented standard, and keep the paperwork with the boat.
No. It is an industry standard rather than a statutory requirement, though inland boats also need to meet the separate Boat Safety Scheme requirements which draw on similar principles.
Membership indicates a level of industry engagement, but it is worth also asking about specific experience with your type of system and asking to see examples of documented past work.
Not automatically. Many older boats have sound original wiring; the more common issue is additions made over the years without matching the original standard.
Yes, and a professional installer should be able to provide a description of what was fitted and to what standard as part of the handover paperwork.
We work to BMEA guidance and the relevant ISO standards on every job, and hand over documentation you can keep with the boat. Get a free assessment.