| In order to prolong any survey interval it is a condition that:
- Maintenance and/or preservative measures have been carried out during the lay-up time - Laid-up vessel annual survey have been carried out in accordance with the rules - The re-commissioning survey shows that no significant deterioration has taken place during lay-up Vessels not satisfying the criteria for prolongation of surveys shall have their overdue surveys carried out at the time of reactivation.
Consideration with respect to prolonged survey intervals may be given to:
- Renewal survey, hull and machinery - Renewal survey for ship types - Machinery survey - continuous - Tail shaft survey.
Prolonged survey intervals are not applicable for:
- Main class annual and intermediate survey - Bottom survey - Boilers - Additional class notations (except ship types) - Vessels more than 15 years old
Vessels satisfactorily maintained / preserved and qualifying for prolonged survey intervals reverting to normal trading require the following reactivation surveys:
- Sighting survey for assessment of condition - Full survey of boilers and additional class notations if over due at time of re-commissioning - Full survey of items due or overdue at the time of entering lay-up - Stern tube lube oil analysis and running test of tail shaft if overdue at time of re-commissioning. (Regular tail shaft survey to be postponed until first docking)
- Sea trial - Bottom survey if total time since last dry docking exceeds 36 months
Vessels not maintained / preserved reverting to normal trading require the following reactivation surveys:
- All overdue surveys except that bottom and tail shaft surveys may be
given same postponement as for a vessel having been maintained/preserved during lay-up - Sea trial
In cases where a considerable amount of machinery items are overdue, it may be acceptable to survey approximately 50% of these during re-commissioning and the remaining during the next 6 months. (i.e. condition of class will be given)
Vessels leaving for scrap yard in ballast condition require the following reactivation surveys:
- Full survey of boilers used during voyage if overdue - Full survey of additional class notations used during voyage if overdue - Sighting survey of hull if main class renewal survey is overdue, except that thickness measurements required by the rules may be reduced For vessels more than 12 years of age, deck plates in 2 transverse bands and 2 deck longitudinal in way of each tank hatch normally to be measured - Survey of machinery continuous items more than 2 years overdue - Test of safety functions e.g. quick closing valves, remote stops, etc - Sea trial including function testing of machinery installation with particular emphasis on steering, bilging and ballasting functions - Survey of engine room cleanliness - Overdue conditions of class - Analysis of stern tube lube oil and running test of tail shaft if overdue - Bottom survey if total time since last docking exceeds 36 months | 
