3 Determination of estimated noise exposure levels
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - Noise Levels - Code on Noise Levels on Board Ships – Resolution A.468(XII) - Appendix 4 - Simplified Procedure for Determining Noise Exposure - 3 Determination of estimated noise exposure levels

3 Determination of estimated noise exposure levels

  3.1 Based on the noise report and the estimated working times and off-duty hours for each job category, the noise exposure level can be calculated. It is assumed that the noise limits for cabins and recreation spaces according to this Code will not be exceeded. Using well-selected hearing protectors is recommendatory according to this Code. It is assumed that the maximum noise level of workers wearing hearing protectors does not exceed 85 dB(A).

  3.2 The noise contribution from each space is calculated as follows:

where:
= Ti is the effective duration on board for each space
= T0 is the reference duration 24 h
= LAeq,i is the A-weighted equivalent continuous sound level for each space

  3.3 The A-weighted noise exposure level is calculated from the noise contribution from each space as follows:

 Example: Result Sheet

Job category Electrician Location/Space
    Navigating bridge Ship Office Machinery Control Room Workshops Engine-
room 		Galley Off-
duty
Measured A-weighted equivalent continuous sound level LAeq,i [dB(A)]   64 63 75 84 85 72 60
Duration/Stay Ti [h]   0 2 2 5 1 0 14
Noise contribution Lex,24h,i [dB]   0 52.2 64.2 77.2 71.2 0 57.7
A-weighted noise exposure level Lex,24h [dB] 78.3  
Parent topic: Appendix 4 - Simplified Procedure for Determining Noise Exposure
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