Combined Annoyance Assessment of Ship Structural Vibration and Ambient Noise

Background: Noise and vibration are environmental pollutants that endanger people's productivity and sleep quality in ships, but the coupled effect in ship cabins has not been studied. This study aimed to assess the coupled effect of noise and vibration in ship cabins and propose a comfortable range of noise and vibration. Methods: Three different accommodation cabins were chosen to measure noise and vibration levels and investigate their satisfaction. A revised model combining exponential membership functions was proposed to reveal the relationship between noise and vibration level and its response. The annoyance rate from greater to lesser was classified as A, B, C, D, and E. Results: All measurement levels were satisfied with the acceptance ranges of standards. While subjects felt high annoyance in the crew lounge, subjects in passenger and dining cabins felt slightly annoyed. Conclusions: By combining measurements and subjective investigations, the prediction performance of the revised annoyance model was verified. The noise level reached 57.5 dB(A), and the acoustic condition had a greater impact on subjective feelings than the vibration level. For grade E demands, the vibration level should be lower than 0.095 m/s(2), and the noise level should be less than 54 dB(A).