Changes in the psychophysiological and cognitive parameters of the sailors wearing cooling vest while working in high ambient temperature condition of the engine room onboard a naval ship: An experimental study

Abstract

Background: Cooling vests are supportive garments used to overcome heat stress among individuals working in hot and humid environment. These vests were used extensively by fire-fighters and coal mine workers in past. In this study we have evaluated the effectiveness of cooling vest on psychophysiological and cognitive parameters of the sailors working in the engine room of a Naval ship. Aims and Objectives: Aim of out is to evaluate effectiveness of cooling vests in alleviating heat strain and maintain physiological parameters and behavioural alertness of sailors working in the hot and humid climate of engine room. Materials and Methods: The Physiological Strain Index (PSI), the level of Anxiety and the Psychomotor Vigilance testing was determined from 50 healthy male sailors while on 4 hrs of watch in the engine room in two different occasions i.e. once wearing the cooling vest and once more without wearing it. Subjective perception of acceptability of cooling vest was assessed by a self-made questionnaire. Results: The mean body temperature (Aural), pulse rate, respiration rate along with the Physiological Strain Index (PSI) was significantly lower both during mid watch as well as at the end watch among the engine room sailors while performing the watch wearing the cooling vest (Watch-2) in comparison to the watch without wearing it (Watch-1). The mean change in reaction time in the Psychomotor Vigilance Testing (PVT) was lesser while performing the watch with cooling vest (Watch-2) than the watch without it (Watch-1). Similarly, a higher proportion of participants had shown to have no increase in their anxiety level (Hamilton Anxiety Score) at the end of the watch when performing it with cooling vest. Also, the positive acceptance for the cooling vest was also observed among larger portion of participants. Conclusion: The study indicated lesser heat strain, lesser deterioration of Psychomotor vigilance function, lesser proportion of participants showing anxiety among the sailors wearing cooling vest while working in the hot and humid condition of engine room of a naval ship. A positive acceptance for cooling vest was also observed among higher number of these participants.

Keywords

• cooling vest
• engine room
• heat stress