Section 5 Noise and vibration survey reporting

5.1.1 Prior to survey, a noise and vibration measurement plan is to be agreed by the Owner, Builder and LR.

5.1.2 The survey report is to comprise the data and analysis for both noise and vibration and is to be submitted to LR for consideration.

5.1.3 The survey report is to be prepared by the organisation undertaking the trial measurements, which may be an approved technical organisation or LR.

5.1.4 The survey report is to be submitted to LR for evaluation and confirmation that the results are in accordance with the noise and vibration levels specified in these Rules and/or agreed between the Owner and Builder. The assignment of a Class Notation or the issue of a Statement of Compliance will be subject to confirmation by LR.

5.2.1 The reporting of results is to comply with ISO 2923 and IMO Resolution MSC.337(91) – Adoption of the Code on Noise Levels on Board Ships – (Adopted on 30 November 2012)The Annex below is consolidated into Resolution MSC.337(91), and is to include:

1. Measurement locations indicated on a general arrangement plan including, where possible, the measured dB(A) level.

2. Tabulated dB(A) noise levels, together with octave band analysis for positions where the level exceeds the specified criterion by 3 dB(A), or where subjectively annoying low frequency or tonal components were present. The Noise Rating number is also to be given where octave band analyses have been conducted.

3. Ship and machinery details.

4. Trial details:

   • Loading condition.
   • Machinery operating condition.
   • Speed.
   • Average water depth under keel.
   • Weather conditions.
   • Sea state.
   • Draught.

5. Details of measuring and analysis equipment (e.g. manufacturer, type and serial numbers), including frequency analysis parameters (e.g. resolution, averaging time, window function).

6. Copies of the relevant instrument calibration certificates, together with the results of field calibration checks.

5.3.1 The report is to contain the following information:

1. Measurement positions indicated on a general arrangement plan.

2. Where ISO 20283-5 is used, the frequency-weighted overall r.m.s. vibration levels tabulated for all measurement locations calculated using the weighting functions and methodology stated in the standard.

3. Ship and machinery details.

4. Trial details:

   • Loading condition.
   • Machinery operating condition.
   • Speed.
   • Average water depth under keel.
   • Weather conditions.
   • Sea state.
   • Draught.

5. Frequency analysis parameters (e.g. resolution, averaging time and window function), if the analysis is done in the frequency domain.

6. Copies of the relevant instrument calibration certificates, together with the results of field calibration.