Surveys

Ballast tanks are subject for overall visual inspections, close-up inspe-tions, structural testing, and thickness measurements. For ships over 5 years of age (i.e. starting from second renewal survey), ballast tanks shall be surveyed in accordance with the hull survey plan. //DNV-RU-SHIP Pt.7 Sec.3.2

For ships 5 to 10 years of age, hull survey plan normally includes an overall examination of representative ballast tanks selected by the surveyor during intermediate and renewal surveys. For ships over 10 years of age, all ballast tanks are normally inspected during intermedi-ate and renewal surveys. For ships where tanks are not coated according to PCPS the inspection schedule is extended to every second annual survey. The overall survey of tanks includes also condition piping passing through the tanks. //DNV-RU-SHIP Pt.7 Sec.3.2

Ballast tanks are subject for structural testing (i.e. the tank should be filled to the top of the air pipe) during renewal surveys. Testing by crew within three months prior to renewal survey completion day may be accepted by captain’s confirmation. //DNV-RU-SHIP Pt.7 Sec.4.2
Air vent heads for ballast tanks are subject for renewal surveys as specified in DNV-RU-SHIP Pt.7 Ch.4.2.1.11. The head shall be removed from the air pipes in cases where the inner parts cannot be properly inspected from outside. //DNV-RU-SHIP Pt.7.4.2.1

Performance test of ballast system shall be carried out during renewal surveys. Pumps are subject for opening up fully or partly as deemed necessary by surveyor. Pressure test and thickness measurements of suspicious piping may be required. The last overhauling will be verified. //DNV-RU-SHIP Pt.7 Sec.4.5