Dataset Information

Effect of a Simulated Mine Rescue on Physiological Variables and Heat Strain of Mine Rescue Workers.

ABSTRACT:

Objective

To describe physiological responses of mine rescuers during a simulated mine emergency.

Methods

Body-worn monitors (n?=?74) and core temperature (Tc) capsules (n?=?54) assessed heart rate (HR), respiration rate (RR), energy expenditure (EE), oxygen consumption ((Equation is included in full-text article.)), Tc and skin temperature (Tskin), by team position and task. A multivariate analysis was performed with team positions, tasks, and measures as factors.

Results

HRmean and HRpeak were 78.6% and 94.5%, respectively, of predicted maximum heart rate. Arduous labor tasks elicited higher HR, RR, and (Equation is included in full-text article.)than casualty care. Captains exhibited lower HRmean, HRpeak, RR, RRpeak, (Equation is included in full-text article.), Tc, and Tskin compared with other positions. Tc mean exceeded 38.6?°C (n?=?14 recorded Tc >39?°C).

Conclusions

Captains' physical loading and heat stress were lowest. Nonetheless, all tasks and positions induced high physical load and heat strain.

SUBMITTER: Konrad J

PROVIDER: S-EPMC6416035 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Publications

Effect of a Simulated Mine Rescue on Physiological Variables and Heat Strain of Mine Rescue Workers.

Konrad Justin J Gagnon Dominique D Serresse Olivier O Oddson Bruce B Leduc Caleb C Dorman Sandra C SC

Journal of occupational and environmental medicine 20190301 3

<h4>Objective</h4>To describe physiological responses of mine rescuers during a simulated mine emergency.<h4>Methods</h4>Body-worn monitors (n = 74) and core temperature (Tc) capsules (n = 54) assessed heart rate (HR), respiration rate (RR), energy expenditure (EE), oxygen consumption ((Equation is included in full-text article.)), Tc and skin temperature (Tskin), by team position and task. A multivariate analysis was performed with team positions, tasks, and measures as factors.<h4>Results</h4> ...[more]

PMID: 30856626

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Project description:BackgroundFarmworkers are at risk of heat-related illness (HRI). We sought to: 1) evaluate the effectiveness of farmworker Spanish/English participatory heat education and a supervisor decision-support mobile application (HEAT intervention) on physiological heat strain; and 2) describe factors associated with HRI symptoms reporting.MethodsWe conducted a parallel, comparison group intervention study from May-September of 2019 in Central/Eastern Washington State, USA. We used convenience sampling to recruit adult outdoor farmworkers and allocated participating crews to intervention (n = 37 participants) and alternative-training comparison (n = 38 participants) groups. We measured heat strain monthly using heart rate and estimated core body temperature to compute the maximum work-shift physiological strain index (PSImax) and assessed self-reported HRI symptoms using a weekly survey. Multivariable linear mixed effects models were used to assess associations of the HEAT intervention with PSImax, and bivariate mixed models were used to describe factors associated with HRI symptoms reported (0, 1, 2+ symptoms), with random effects for workers.ResultsWe observed larger decreases in PSImax in the intervention versus comparison group for higher work exertion levels (categorized as low, low/medium-low, and high effort), after adjustment for maximum work-shift ambient Heat Index (HImax), but this was not statistically significant (interaction - 0.91 for high versus low/medium-low effort, t = - 1.60, p = 0.11). We observed a higher PSImax with high versus low/medium-low effort (main effect 1.96, t = 3.81, p < 0.001) and a lower PSImax with older age (- 0.03, t = - 2.95, p = 0.004), after covariate adjustment. There was no clear relationship between PSImax and the number of HRI symptoms reported. Reporting more symptoms was associated with older age, higher HImax, 10+ years agricultural work, not being an H-2A guest worker, and walking > 3 min to get to the toilet at work.ConclusionsEffort level should be addressed in heat management plans, for example through work/rest cycles, rotation, and pacing, in addition to education and other factors that influence heat stress. Both symptoms and indicators of physiological heat strain should be monitored, if possible, during periods of high heat stress to increase the sensitivity of early HRI detection and prevention. Structural barriers to HRI prevention must also be addressed.Trial registrationClinicalTrials.gov Registration Number: NCT04234802 , date first posted 21/01/2020.

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Dataset Information

Effect of a Simulated Mine Rescue on Physiological Variables and Heat Strain of Mine Rescue Workers.

Objective

Methods

Results

Conclusions

Publications

Effect of a Simulated Mine Rescue on Physiological Variables and Heat Strain of Mine Rescue Workers.

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