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With modern trends of decrease in crew numbers on board ships together with increased operational demands and paperwork, crew fatigue and comfort have become more critical and are being given more importance. It is well known that environmental factors affect crew comfort and performance. The two outstanding factors which exist in the shipboard environment are vessel motions and noise. As such, the findings and lessons learnt from other industrial sectors are considered to be less relevant for ships. Therefore, it is necessary to conduct focused research to understand the effects of these factors, so that the lessons learnt can be integrated into the ship design process so as to mitigate their adverse effects during vessel operations. Due to obvious performance issues, ship motions and motion sickness research has attracted far more interest than human response to noise. This paper reports the findings of a recent research study undertaken as part of an EU FP7 research project, namely SILENV, which investigated the current levels of crew noise exposure through field studies. Furthermore, developed models on human response to noise on board ships and SILENV Green Label noise standards are also introduced in comparison with the current normative framework. © 2016 Elsevier Ltd.

Subjective-vertical conflict theory (Bles et al., 1998) postulates that all motion sickness provoking situations are characterized by a condition in which the vertical (gravity) sensed by the visual, vestibular and non-vestibular proprioceptors are at variance with the subjective (expected) vertical. SV-conflict models have successfully been used by Bos and Bles (2000), Verveniotis and Turan (2002b), Bos et al. (2002a) and Dallinga et al. (2002), to predict motion sickness of passenger ferries. However, considering the prevalence of significantly high level of horizontal acceleration aboard contemporary vessels, Khalid et al. (in press) proposed a further elaboration of a physiological (subjective-verticalhorizontal, SVH-conflict) model that explicitly incorporates the effects of horizontal accelerations. They hypothesized that the explanation of motion sickness variability may improve, by considering the combined effects of subjective vertical as well as subjective horizontal conflicts (difference between the sensed and 'expected' horizontal accelerations). This paper briefly presents the SVH-conflict model and demonstrates its application to 68 field trials of 10 different vessels. Percentages of seasick passengers, observed during the field trials, are statistically compared with physiological and descriptive (O'Hanlon and McCauley, 1974; ISO 2631-1, 1997) motion sickness models. In general, SVH-conflict is statistically outperforming the descriptive models and displaying improvement over the SV-conflict model. © 2010 Elsevier Ltd. All rights reserved.