Twenty-four-hour pattern of operations-related injury occurrence and severity of off-site/on-call volunteer French firefighters

ABSTRACT

We assessed the 24-h pattern of operations-related injuries (ORI) experienced by scheduled off-site/on-call French volunteer firefighters (VFF) through analysis of an archival database. Occurrence and severity – evaluated by number of lost work days (LWD) and total medical costs (TMC) – of ORI were explored in terms of risk ratios, respectively, number of ORI/number of service operations (RR_ORI), number of LWD/number of ORI (RS_LWD,) and TMC/number of ORI (RS_TMC). Additionally, the collective work performance of all involved VFF was measured in terms of the lag time (LT) between emergency call-center firefighter-answered communication for service of observer-presumed out-of-hospital cardiac arrest (OHCA) and departure of vehicle from fire station to render aid, designated LT_OHCA. Cosinor and cross-correlation statistical methods were applied. A total of 252 ORI occurred while performing 146,479 service operations. High-amplitude 24 h variation was detected in RR_ORI (p < .003), SR_LWD (p < .001), SR_TMC (p < .012), and LT_OHCA (p < .001), all with nocturnal peak time. Coherence was found between the day/night variation of LT_OHCA and RR_ORI (r = 0.7, p < .0002), SR_LWD (r = 0.5, p < .02), and SR_TMC (r = 0.4, p < .05). This investigation verifies the occurrence and severity of ORI of scheduled off-site/on-call VFF exhibit high-amplitude 24 h patterning with nocturnal excess that closely coincides with their day/night work performance measured by LT_OHCA. These findings, which are essentially identical to ones of a previous study entailing on-site/on-call career firefighters, indicate the need for fatigue management and ORI prevention programs not yet available to VFF, who compose the majority of the field service workforce of French fire departments.

Abbreviations:FF: firefighters; CFF: career firefighters; VFF: volunteer firefighters; FD: fire department; LT_OHCA: lag time (LT) response in min:sec between fire department call-center-answered communication for service of presumed out-of-hospital cardiac arrest (OHCA) and departure from fire station of vehicle to render aid; LWD: lost work days; ORI: operations-related injuries; SR_LWD: severity ratio of operations-related injuries in terms of number of lost work days, calculated as number of lost work days/number of operations-related injuries; RR_ORI: risk ratio of operations-related injuries calculated as number of operations-related injuries/number of operations; SR_TMC: severity ratio of operations-related injuries in terms of total medical costs, calculated as total medical costs/number of operations-related injuries; TMC: total medical costs

KEYWORDS:

• Firefighters
• volunteers
• offsite/on-call
• standby work
• operations-related injury occurrence and severity
• 24-h patterns
• job performance
• circadian

Acknowledgments

This research was supported by a grant-in-aid from the “Fond National de Prévention” (CNRACL) and Thérèse Tremel - Pontremoli Donation at the Fondation Adolphe de Rothschild for research in chronobiology. We also acknowledge Colonel Hugues Deregnaucourt, and Mickael Pierrat, M.D., respectively, Director and Chief Medical Officer of the FD 88 at the time of the study, Germaine Cornelissen (University of Minnesota, Halberg Center for Chronobiology) and Martial Boulesteix (AUM Biosync SAS, France) for their valuable assistance in the conduct of the time series analysis.

Foreword

This paper is dedicated to the memory of Colonel Michel Marlot, former Director of the Fire Department of Saône et Loire, and Doctor Alain Reinberg, former Director of the Chronobiology Unit, Fondation Adolphe de Rothschild, distinguished gentlemen of exceptional human qualities.

Conflicts of interest

The authors declare no conflicts of interest.

Declaration of interest statement

None of the authors have financial, consulting, or personal relationships with people or organizations to declare that could be perceived by readers to influence (bias) the conducted research and findings. Lead author Marc Riedel is a French volunteer firefighter and presently a principle of a business addressing work–life balance issues of first responders. The current research was conducted before the establishment of his business, and the findings, and their discussion were not influenced by such.