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 \>= 00.04 g% blood alcohol concentrations (BACs) on the job. This study investigated the effects of alcohol (between 0.04 and 0.05 g% BAC) on the simulated operation of a commercial ship’s power plant. Design. A balanced placebo design was used in which alcohol administration was fully crossed with expectancy that alcohol was administrated. Setting. The study was 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 diesel simulator. Intervention. Following a baseline trial on day 1, on day 2 participants were randomized to expectancy (told alcohol or placebo) and beverage (receive alcohol or placebo). The dosage was 0.6 g/kg for males and 0.5 g/kg for females. In both baseline and performance days, participants were 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 was measured by time required for problem identification and remediation. Findings. A main effect for alcohol administration was found. In the alcohol condition, simulator performance time was almost twice as long (351 sec) as on the placebo condition (186 sec). The expectancy effect was not significant. Conclusion. These findings support the current federal policy on the hazards of this low alcohol level within the context of commercial shipping.