Marine Inspection Services (MIS) is an independent ultrasonic thickness measurement company approved by six leading classification societies: ABS, DNV, Bureau Veritas, Lloyd's Register, ClassNK and RINA. We carry out UTM surveys for special, intermediate and CAP surveys, pre-purchase inspections and repair planning, on everything from small fishing vessels to large tankers and FPSOs.
Our inspectors take readings by conventional access, drone, Mini ROV or rope access, whichever is safest and most efficient for space. Class surveyors trust our teams to work with minimal supervision, and we deliver reports in the format your class society expects.
What is ultrasonic thickness measurement?
Ultrasonic thickness measurement (UTM) is a non-destructive test that measures how much steel remains in a plate. A probe sends a sound pulse into the steel and times the echo, giving the thickness to a fraction of a millimetre.
It needs access to one side only, and multiple-echo gauges can measure through intact coatings. Comparing readings with the as-built thickness shows how much corrosion has occurred and whether the steel is within class limits.
When is UTM required?
Classification Societies require thickness measurements at intervals throughout a vessel's life, increasing with age. We carry out UTM for:
- Special, intermediate and annual surveys
- Enhanced Survey Programme (ESP) for tankers and bulk carriers
- Condition Assessment Programme (CAP), up to 50,000 readings on a large vessel
- Pre-purchase inspections
- Repair planning and steel renewal
- Offshore assets, including FPSOs, FSOs and rigs
Class thickness measurements must be taken by an approved firm. MIS holds that approval with all the major societies.
Class approvals and qualifications
MIS is approved to perform ultrasonic thickness measurement by:
• American Bureau of Shipping (ABS)
• DNV
• Bureau Veritas (BV)
• Lloyd's Register (LR)
• ClassNK
• RINA
We are also approved by ABS, DNV and LR to take thickness measurements by drone and BV and DNV for thickness measurements by Mini ROV. MIS was the first company in the world to receive Lloyd's Register certification for drone-based UTM.
Every MIS inspector is qualified to a minimum of PCN Level 2 in ultrasonic testing and has years of experience on vessel structures for class surveys. That experience is why class surveyors trust our teams to work with minimal supervision.
Access methods
Reaching every reading point safely is often the hardest part of a UTM survey. We choose the method that suits each space and can combine several on one job.
Conventional access: Inspectors take readings directly, using existing walkways, stringer platforms and staging.
Drone UTM: For large cargo holds and tanks, our drones carry a UTM probe to high structure without staging. This cuts preparation time, cost and reduces work at height. UTM can be completed without tank entry.
Mini ROV: For ballast tank surveys, our Mini ROV takes readings without manned tank entry. It is approved by BV and DNV as a Remote Inspection Technique (RIT).
Rope access: IRATA-trained teams reach deck transverse frame sections, cargo tank bulkheads and other difficult areas quickly, with minimal equipment.
What you receive, and where we work
Deliverables:
• Thickness measurement report in your class society's format, ready for the surveyor
• Steel renewal report covering areas of substantial or renewable wastage
• Marked-up drawings or sketches showing reading locations
• Drawings showing steel repairs to cover areas of wastage, if required
• Optional repair supervision by qualified steel inspectors
MIS is based in Dorset, UK, and our teams travel worldwide to vessels in port, at anchor, in dry dock or offshore.
Planning a class survey or dry dock?
Tell us the vessel, survey type and dates, and we'll come back with a scope, timeline and quote, usually within 24 hours.
Call: +44 (0)1305 257438 · Email:
