Nautical Compass — Maritime Safety 2026
Magnetic Compass
Adjustment Service and
Official SOLAS Certification
Navigate on a True Heading.
In an era of growing electronic navigation threats —GNSS jamming and spoofing across major European shipping lanes— the magnetic compass remains the only steering system genuinely immune to external interference. Your compass is the vessel's analogue firewall: when electronics fail or are compromised, magnetic north stands firm.
Compass compensation is not a bureaucratic formality. It is a vital insurance policy for the vessel, her cargo, and her crew.
The magnetic compass aboard a steel-hulled vessel is subject to the influence of the ship's permanent and induced magnetism, generating a deviation —the angular difference between compass heading and magnetic heading— that can seriously compromise navigational safety.
Magnetic Compass Adjustment and Compensation
Compensation involves the precise disposition of fore-and-aft and athwartships permanent magnets, together with soft-iron correctors (Kelvin spheres and Flinders bar) in the binnacle, so that their combined magnetic fields are equal and opposite to the vessel's magnetic signature. The objective is to reduce residual deviation to within the operational limits prescribed by international regulations.
The service includes:
- Full swinging of the vessel to record deviation on all cardinal and intercardinal headings.
- Adjustment using fore-and-aft and athwartships compensating magnets.
- Correction of induced magnetism using Kelvin spheres and Flinders bar.
- Heeling magnet adjustment, where applicable.
- On-the-spot issue of the official deviation card in hard-copy format, in full compliance with SOLAS Chapter V.
- 24/7 availability throughout Spain. The vessel may proceed to sea immediately upon completion, with all documentation in order.
Launch/tender to vessel is at the vessel's expense.
Magnetic Compass Adjustment Service
Who Performs the Adjustment
Compensation is carried out by Captain Alejandro Ros, Master Mariner of the Spanish Merchant Marine and a certified Compass Adjuster registered as N.º 86 by the Dirección General de la Marina Mercante (DGMM) since June 1993.
Over 30 years of command and technical expertise underpin every adjustment, ensuring compliance with the most stringent industry standards.
When is Compass Compensation Mandatory?
In accordance with international regulations (SOLAS) and ISO 25862, magnetic compass adjustment is mandatory in the following circumstances:
- 1. Periodic interval: at least every two years per ISO 25862. Certain flags, such as Italy, require annual adjustment.
- 2. Following structural modifications or major hull repairs.
- 3. When a significant change in the vessel's permanent magnetism is detected.
- 4. After prolonged mooring on a constant heading, or extended ocean passages that may alter the ship's magnetic state.
- 5. When magnetic equipment near the binnacle is modified or newly installed.
- 6. After radical changes in magnetic latitude of operation.
- 7. When the heeling magnet position changes appreciably, or any corrector is re-adjusted.
- 8. Following any significant change in magnetic cargo.
If observed deviations exceed safe operational limits, a professional inspection is mandatory to prevent detention by Port State Control (PSC).
NO DELAYS
Special Services
Master Compass (TMC) Installation
Should it be necessary to install the master compass —whether on an exchange basis or not— the on-board delivery and installation service, including the transmitting magnetic compass (TMC), is charged at €120.
Efficiency Note
To minimise turnaround time, please provide a photograph of the master compass and binnacle clearly showing the type of base and sensor (transducer) fitted. The more information available in advance, the less time required on board.
*The vessel may proceed to sea immediately upon completion, with all documentation in order, in full compliance with SOLAS Chapter V.
Service Rates
All prices are fixed, agreed prior to engagement and free of hidden charges. VAT not included. Operating base: Port of Valencia.
Rate by Gross Tonnage (GT) — Standard Hours (Mon–Fri 08:00–18:00)
Out-of-Hours Surcharges
General rate conditions of Compensation and Adjustment:
- Rates include mileage and transit time (base: Port of Valencia).
- Two hours of quayside waiting time are included. Excess time: €65/h (standard); €86/h (out-of-hours/holiday).
- Compensating magnets (if required): €50/unit.
Port Displacement Fees
Fixed transfer fees for the main maritime hubs along the Spanish Mediterranean seaboard:
* Request a Quote
Due to the considerable distance between ports, we need to provide a comprehensive cost breakdown to accurately outline travel and per diem expenses for these cases.
Compass Exchange Programme
Delivery of a fully reconditioned compass in exchange for the defective unit: €900. Alternatively, an on-board replacement with dispatch of the original compass to the workshop for repair.
Passages — Valencia · Balearic Islands
When owners or masters require compensation aboard a vessel in transit, it is strongly recommended to provide in advance a photograph of the compass and binnacle, together with the last deviation card. This information allows a preliminary assessment of the magnetic situation and optimises the time spent on board during the passage.
For 24-hour passages, the rate increases by 7 hours at €86/h for transit time. Weekend and public holiday surcharges of 35 % or 65 % apply accordingly.
VAT NOT INCLUDED
Reference clients
Frequently Asked Questions
How long does the on-board intervention take?
A standard compensation requires between 2 and 4 hours, depending on vessel type and the magnitude of the deviations observed. This time covers the complete swinging, adjustment of all correctors, and preparation of the final deviation card.
How are displacement and logistics costs calculated?
Fixed fees apply to all major ports along the Spanish Mediterranean coast. For secondary ports, costs are calculated transparently and confirmed in full before engagement. There are no surprise charges on the final invoice.
Do you operate outside business hours and at weekends?
The sea keeps no office hours, and neither do we. The service is available 24/7, adapting to the arrival and departure schedules of merchant vessels. If your vessel sails at 04:00, the adjustment can be carried out in the early hours so that she clears port with all documentation fully in order.
What precautions are taken aboard passenger vessels and superyachts?
For mega yachts we use cover shoes so as we do not dirty any deck.
Is the certificate valid for international inspections?
Yes. Deviation cards issued by Captain Ros comply with SOLAS (Chapter V) and IMO resolutions, and are official documents accepted by Port State Control (PSC), P&I Clubs, and maritime authorities under any flag.