Rules for Classification of Ships, July 2006 Pt.7 Ships in Operation Survey Requirements Issued 1. July 2006
This report contains DNV s overall interpretation of the consequences of the many new DNV rules impacting the DNV fleet today. Our goal is to help our customers stay up to date, while at the same time clearly state what DNV regards to be the motivation behind the changes, and point out the most important changes. Please note that the interpretations of the rules and regulations made by DNV and presented in this report are generic, meaning that special exceptions or novel designs are not included. To obtain information regarding such special cases, please contact DNV s experts listed in the contact section of this report. Revised rules for ships in operation periodical surveys Introduction A revision of the complete Pt.7 has been on hearing during the spring 2006 and has been approved by the DNV Board. The rules are now implemented as July 2006 rules. They will be in force from 1.Januray 2007. However, the hull related parts for main class annual, intermediate and renewal surveys will apply from 1.July 2006, in order to harmonize with the unified implementation within IACS societies. Part I: Scope of the proposal - main changes The rule revision is to a large degree related to systematic, consistency and structure. However, revised requirements apply. In the following some of these changes are described. 1) Revised scope for main class (see also Part II at main class principles ) Installed structures, systems or equipment affecting the structural integrity, propulsion and steering systems, power generation and distribution, control and monitoring included main and auxiliary functions, shall be examined as part of the main class surveys. Such survey-items shall be inspected, regardless of given (or not given!) class notations. The principle also implies that requirements outside these areas, like convention requirements to life saving appliances, are kept outside the main class survey requirements. Example 1 for ships with reefer plants or controlled atmosphere installations the survey shall include safety related items e.g.; tightness; ventilation; alarms and emergency stop buttons and leakage detectors. - Requirements to functions and capacity are still included as part of the possible optional notation. Example 2 - ships carrying motor vehicles with fuel in their tanks in enclosed spaces (including ships with class notation Car Carrier or PET), the survey shall include e.g.:
fire alarm in cargo holds, ventilation system in cargo holds and electrical equipment in cargo holds. 2) Intermediate survey ESP tankers hull (IACS UR) Stricter survey requirements apply for the intermediate survey between 2 nd and 3 rd renewal survey. For ships over 10 years of age the survey requirements for the intermediate survey shall be to the same extent as the previous renewal survey It should be noted that when the rules state to the same extent as the previous renewal survey the increased scope is applicable to: overall examination of hull structure and piping systems in way of cargo and ballast tanks and in way of all pump rooms, cofferdams, pipe tunnels and void spaces within the cargo area close-up examination thickness measurements a bottom survey. For the third intermediate (ships between 10 & 15 yrs) an under water survey may be considered in lieu of a bottom survey in dock. For the fourth and subsequent intermediate survey (ships > 15 yrs) a bottom survey in dock is required. 3) Annual survey of ballast tanks hull (IACS UR) Applicable for all ESP tankers: A water ballast tank is to be examined at subsequent annual intervals where: a hard protective coating has not been applied from the time of construction a soft coating has been applied substantial corrosion is found within the tank the hard protective coating is found to be in less than GOOD condition and the hard protective and the hard protective coating is not repaired to the satisfaction of the Surveyor. Note: The current rules require annual survey to be implemented if the ballast tank coating is rated POOR and also if the rating is FAIR and the tank is adjacent to a cargo tank with any means of heating. The new scheme requires annual survey to be implemented if the rating is FAIR irrespective if the adjacent cargo tank is heated or not. Applicable to single hull oil tankers: Ballast tanks are to be examined at annual intervals when the tank has a common plane boundary with a cargo tank with any means of heating. Where the protective coating was found to be in GOOD condition at the previous intermediate or renewal surveys the annual examination may be specially considered. 4) Means of access hull - bulk carriers (IACS UR) For cape size bulk carriers (100,000 dwt and above) stricter requirements apply for close up examination of the cargo hold shell frames: - portable ladder is not accepted for intermediate and renewal surveys. - portable ladder of max. 5m in length is acceptable for annual survey - provided the ladder is fitted with a mechanical device to secure the upper end of the ladder
- for the close-up examination of lower section of a shell frame including bracket - hydraulic arm vehicle such as conventional cherry picker is limited to examination of lower and middle parts of hold frames at renewal survey no. 2 and subsequent intermediate and renewal surveys; 5) Boiler surveys revised requirements and survey schedule The boiler complete survey schedule has changed (IACS UR): - two boiler surveys are required during each five-year period of the classification certificate. - the interval between any two successive boiler surveys is in no case to exceed 36 months. - the survey shall be carried out on or before the due date. Time window is not applicable. - one boiler survey shall be carried out in conjunction with the renewal survey, i.e. not more than 15 months prior to the expiry date of the classification certificate. The boiler at main class annual survey (IACS UR): - external examination - test of safety and protective devices - for exhaust gas heated economizers, verification of function of the safety valves may be carried out by the Chief Engineer at sea. This test is to be recorded in the log book prior to survey for review by the attending Surveyor. Requirements for boiler water treatment programme: - boiler water quality is to be maintained to the standard required by the equipment manufacturer monitored according to a boiler water treatment programme. - the boiler water shall be monitored/ tested at least once in every 24 hours daily for main boilers and at least every 48 hours for auxiliary boilers. - records of boiler water treatment management shall be available onboard - procedures shall be in place for testing of boiler water and lay-up decommission of the boiler. 6) Revised requirements also apply for the following surveys: - Propeller shaft Withdrawal Survey (Tailshaft survey) - Propulsion Thruster Survey - class notation DYNPOS - Dynamic Positioning Systems - class notation NAUT - Nautical Safety - class notation F-AMC - Additional Fire Protection Arrangements - class notation WINTERIZED 7) New class notation RATE(A) The new notation represents an enhanced standard for the reporting of hull structure condition and aims at complying with technical standards in excess of the main class requirements. Separate information material will be provided.
Part II: Motivation, principles and structure A need for a more comprehensive revision of the rules has led to a total revision of Pt.7, in order to improve the following areas: The rules for main class; i.e. what is to be included as part of mandatory class Structure of present rules Duplicated survey requirements Complex survey systematic Include revised common IACS unified requirements This implied the following main overall changes: Revised scope for main class, see - main class principles Mandatory class notations included as part of main class Harmonisation of the survey requirements between the ship types and surveys Stronger focus on the ship s onboard systems and functions as part of the main class machinery and systems. Alignment with IACS unified requirements concerning hull and machinery surveys Main class principles The main class rules are aimed at ensuring the safety and reliability of the following main functions: Structural integrity, including hull strength Propulsion, including related support functions like fuel systems, gears, shafts, propellers, steering Power generation, including power to main and auxiliary functions Control & Monitoring, including electrical installations, automation, SW based systems and internal communication Systems for hazardous cargos and fire prevention. Revised structure of rules for Ships in Operation Pt.7 The following principles have been in focus in order to settle the structure of part 7 which has been totally revised. Simple and logic structure Main class survey requirements are grouped, one section for each main class survey Optional class notations have been grouped. One letter for each survey The rules for periodical surveys are gathered within one rule-chapter chapter 1. The retroactive requirements are included as part 7 chapter 2. Principles for rule requirements level of detailing The level of details in the rule requirements has been harmonized.
Stronger focus on the ship s onboard systems The revised rules imply a stronger focus on the ship s onboard systems and functions, as part of the main class machinery and systems. Survey requirements related to system examination and testing are to a large degree kept outside the machinery inventory lists, i.e. such systems are always to be inspected by a surveyor. The machinery table has been simplified, focusing mainly machinery components. Alignment with IACS unified requirements The proposal aim at including the recent changes made as a consequence of the "harmonisation" task run in IACS 2004/2005. Several changes are made including the tables for close up and thickness measurements. These hull requirements are planned to come into force July 2006! Contact information For more information please contact MTPNO860@dnv.com. Oslo, 2006.06.23 FER/