The Auxiliary Boiler (oil-fired) and similar pressure vessels for ships classed and intended to be classed with INTLREG need to comply with INTLREG Rules and Regulations for Classification of Steel Vessels PART 5A Machinery Equipment installation and piping system.

Alternatively, they may conform to a recognized code or standard. Some of the International and National standards that are recognized for the purpose of this section are given below:

• ASME Boiler and Pressure Vessel Code Section I ,
• British Standard BS 1113 Design and manufacture of water tube steam generating plant (including superheaters, reheaters and steel tube economizers)
• British Standard BS 2790 Specifications for the design and manufacture of shell boilers of welded construction
• Other national standards or codes will only be considered, provided they are no less effective.

From the commencement of the work until the completion and final test of the machinery to working condition, the Surveyors are to be satisfied that the materials, workmanship, and arrangements are satisfactory and in accordance with the Rules or the approved plans, or any material, workmanship or arrangement found to be unsatisfactory, will require to be rectified.