Effects of low-dose alcohol exposure on simulated merchant ship handling power plant operation by maritime cadets

Aims. Under current US Department of Transportation (DOT) regulations, some commercial vehicle operators are subject to sanctions for having greater t han or equal to 00.04 g% blood alcohol concentrations (BACs) on the job. Th is study investigated the effects of alcohol (between 0.04 and 0.05 g% BAG) on the simulated operation of a commercial ship's power plant. Design. A b alanced placebo design was used in which alcohol administration was fully c rossed with expectancy that alcohol was administrated. Setting. The study w as conducted at the Massachusetts Maritime Academy, Buzzards Bay, MA, USA. Participants. Participants were 18 volunteer engineering students in their senior year, at least 21 years of age, with previous experience on the dies el simulator. Intervention. Following a baseline trial on day 1, an day 2 p articipants were randomized to expectancy (told alcohol or placebo) and bev erage (receive alcohol or placebo). The dosage was 0.6 g/kgfor males and 0. 5 g/kg for females. In both baseline and performance days, participants wer e randomized to one of four diesel simulator scenarios, each replicating a system failure in a power plant subsystem (e.g. main propulsion, electrical generating). Measurement. Performance wets measured by time required for p roblem identification and remediation. Findings. A main effect for alcohol administration was found. In the alcohol condition, simulator performance t ime was almost twice as long (351 sec) as on the placebo condition (186 sec ). The expectancy effect was not significant. Conclusion. These findings su pport the current federal policy on the hazards of this low alcohol level w ithin the context of commercial shipping.