Digging for data: How sleep is losing out to roster design, sleep disorders, and lifestyle factors
The study is the first to determine sleep characteristics, the potential prevalence of risk for sleep disorders, and estimated alertness levels of shift workers in a remote FIFO mining operation. Seventy-five shift workers from a FIFO mining operation wore a wrist-activity monitor (Readiband™) to measure and quantify sleep behaviours for seven-day shifts, seven-night shifts, followed by seven days off (i.e. roster schedule). The prevalence of risk for sleep disorders was determined using validated sleep disorder questionnaires for daytime sleepiness, sleep apnea, insomnia, and shiftwork disorder. Alertness was estimated across the roster schedule using biomathematical modelling (SAFTE™). In this study we found that sleep loss (<7 h) accumulated with consecutive day shifts (x7) and night shifts (x7), resulting in an estimated acute sleep loss of 13 h and a 20% reduction in alertness for these 14 workdays and nights.
This may be potentially due to limited sleep opportunities between shifts due to the roster design. Furthermore, we found a high prevalence of risk for sleep disorders including shiftwork disorder (44%) and OSA (31%) that may be contributing further to sleep loss. Of concern, we also found a significant number of shift workers were obese and/or consumed alcohol at a hazardous level, both of which can adversely affect sleep duration and efficiency. Our study provides an alarming insight into the acute sleep loss and reduced alertness across a roster schedule on a remote FIFO mining operation, that may create a largely preventable health and safety risk.