Section 1 General requirements

1.1.1 This section is aimed at giving guidance on the survey requirements for the following military distinction notations:

the following hull strength notations:

and the following operation notation:

1.1.2 Normally only the MD or MD notation is specified in the Register Book and survey information unless the Navy decides that the information need not be classified. Where it is not considered classified, information on the extent of protection and the analysis levels used will be contained on the annex to the classification certificate. Where only the MD or MD notation is given, reference will have to be made to the LR Naval liaison office, to determine which notations apply. Survey requirements can then be defined based on the information in this Section.

1.1.3 Security classification is a vital issue and it is imperative that the security procedures required by the appropriate navy are strictly adhered to and any information concerning the military notations is only disclosed to people who have been specifically cleared by that navy.

1.1.4 In most cases the classified information concerns the threat level or details of the calculation used to determine the military capability of a ship. It is not necessary to know this information to carry out an efficient survey. It will, in most cases, only be necessary to report on the condition of the structure for the appropriate area and ensure that it is maintained in the original condition as indicated on the approved plans. Where it is not possible to do this, then the condition should be reported to the LR naval liaison office. They can assess the severity of the defect with reference to the design assumptions and threat levels required, then recommend further action.

1.1.5 The requirements of this Chapter apply to both new construction and in-service ships.

1.2.1 One of the key requirements for the military notations is the material grade. It is important to use notch tough grades such as D and E to reduce the probability of crack initiation and failure of the structure. Therefore it is essential that any modifications or repairs be made using the correct material as indicated on the approved plans and in Vol 1, Pt 6, Ch 6, 2 Materials of the Rules and Regulations for the Classification of Naval Ships (hereinafter referred to as the Rules for Naval Ships).

1.2.2 It is also important to ensure that modifications or repairs do not introduce stress concentrations in the structure, the general guidelines of Ch 3 Construction Procedures can be followed to achieve this. Particular attention should be paid to temporary attachments and finished weld quality.

1.3.1 Areas of the ship strengthened for military notations are subject to different requirements for weld consumables as defined in Table 1.1.2 Welding consumable grade in Vol 1, Pt 4, Ch1 of the Rules for Naval Ships.