0283 Firefighters’ Sleep Changes After Switching Shift Schedules: A Longitudinal Study

Abstract

Abstract Introduction In the past few years, fire departments in the US have been switching from 24 hours on / 48 hours off (24/48) shift schedule to the 48 hours on / 96 hours off (48/96) shift schedule to increase recruitment and reduce commute frequency for members living outside the jurisdiction. While firefighters at work may be able to rest and sleep when not otherwise busy, it is not a guarantee and concerns on health and safety understandably exist when subject to 48 hours on shift. Yet, it is unclear how switching schedules influence firefighters’ sleep. Therefore, the objective of this research is to assess sleep before and after firefighters transitioned from the 24/48 to the 48/96 shift schedule. Methods A pre-experimental, within-subjects, longitudinal sleep study was implemented with a Southcentral US fire department (n=24). Daily sleep included total sleep time (TST), sleep efficiency (SE), sleep latency (SL), and wake after sleep onset (WASO), and was assessed using wrist actigraphy and the Emergency Services Sleep Diary. Participants completed three, 18-day rounds of data collection: baseline assessment was conducted on the 24/48 and post assessments were conducted after three and six months following the transition to the 48/96. Results The results of separate one-way repeated measures ANOVA indicated a statistically significant difference in TST (F(2,46) = 4.58, p< 0.05), SE (F(2,46) = 7.97, p< 0.01), SL (F(2,46) = 6.88, p< 0.05), and WASO (F(2,46) = 5.58, p< 0.05) as firefighters transitioned schedules. Post-hoc analysis identified statistically significant pairs between the 24/48 and the three-month post assessment for each sleep parameter: TST (6.4h vs 6.8h), SL (85% vs 89%), SL (8.7min vs 4.9min), and WASO (58min vs 45min). Conclusion Firefighters reported an improvement in sleep three months after transitioning to the 48/96. The results suggest that improved sleep on the 48/96 may be related to consolidating work shifts, which reduces the frequency of experiencing advance sleep offset on commute days and allows a greater recovery period at home. While further research is needed to assess how health and performance outcomes are related to firefighter schedules, the findings suggest that the pattern of work and non-workshifts influences sleep. Support (if any)