5.1. Inside and outside search: 3 years per time.
5.2. Inside and outside search and hydraulic test: 6 years per time.
5.3. Operating inspection: 1 year per time.
5.4. For tank lorry and containers containing metal errosion solvent-substance (clo, sulfua, hidro…), its time limit of periodical search is not less than two years per time.
5.5. For tank lorry and containers containing propan-butan and commonly used solvent-substance, its time limit of periodical search is not less than four years per time.
5.6. If the manufacturer provides for a shorter time limit of search, then applying according to provisions of the manufaturer.
5.7. When shortening the testing cycle, tester must state clearly the reason in the testing minute.
5.8. The cases must be conducted the irregular search:
a, When using the types of vessels that are stopped using from 12 months or more.
b, When vessels are transformed or removed to a new installation location.
c, When repairing the bloated, sunken locations or the repair using the welding method at the major parts of vessel.
d, When doubting on vessel’s tecxhnical status.
The causes leading to irregular search must be stated clearly in the vessel profile.