Firms providing, on behalf of the Owner of a ship or a mobile offshore unit the following services, the results of which are used by RINA Surveyors in making decisions affecting the classification and/or the statutory certifications on behalf of the flag Administration of the concerned ship or a mobile offshore unit, are subject to approval by RINA.

The approval is mandatory for the following categories of service suppliers.

1. Class services:
• Firms engaged in thickness measurements on ships (except non-ESP ships less than 500 gross tonnage and all fishing vessels)
• Firms engaged in tightness testing of hatches with ultrasonic equipment
• Firms carrying out in-water survey of ships and mobile offshore units
• Firms engaged in the examination of Ro-Ro ships' bow, stern, side and inner doors
• Firms engaged in testing of coating systems in accordance with IMO Resolution MSC.215(82) and IACS PR34.
2. Statutory services:
• Firms engaged in surveys and maintenance of fire-extinguishing equipment and systems
• Firms engaged in service and maintenance of inflatable liferafts, inflatable lifejackets, hydrostatic release units, inflatable rescue boats
• Firms engaged in the servicing and testing of radio communication equipment
• Firms engaged in inspection and testing of centralised gas welding and cutting equipment
• Firms engaged in surveys and maintenance of self-contained breathing apparatus
• Firms engaged in annual performance testing of Voyage Data Recorders (VDR)
• Firms engaged in survey of low location lighting systems using photo luminescent materials
• Firms engaged in sound pressure level measurements of public address and general alarm systems
• Firms engaged in testing of coating systems in accordance with IMO Resolution MSC.215(82) and IACS PR34.

In general, the certification of Service Suppliers by RINA is in compliance with the requirements of IACS Unified Requirement Z17 "Procedural requirements for service suppliers" and of IACS Procedural Requirements No. 23 "Procedures for reporting information on the approval of thickness measurements firms".
Suppliers of services other than those listed above need not be certified by RINA or by the ship's flag Administration. However, such firms may request RINA to certify them as Service Suppliers on a voluntary basis.
Few examples of services for which the Supplier may request to be certified for on a voluntary basis are: performance of NDT examinations; servicing of magnetic compass; inspection, maintenance and repair of lifeboats, launching appliances and release gears; maintenance of portable fire extinguishers and weighting of CO2 bottles.
Details are found in RINA Rules for the certification of service suppliers.