Evidence map›Paper›PMID 40903437›Full record

ArticleAmerican journal of industrial medicine2025

Defining Sex- and Age-Specific Initial Stay Times for Continuous Heavy-Intensity Work in Hot Environments Before Heat-Mitigation Controls Are Implemented-Part B.

Fergus K O'Connor, Kristina-Marie T Janetos, Brodie J Richards, Roberto C Harris-Mostert, Katie E Wagar, Leonidas G Ioannou, James J McCormick, Robert D Meade, Emily J Tetzlaff, Ronald J Sigal and 2 more

Abstract read
In one paragraph

Article in American journal of industrial medicine, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

3 citing papers in PubMed.

  1. Article
  2. Article
  3. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

Fergus K O'ConnorHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0001-9509-7682
Kristina-Marie T JanetosHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0002-8772-7506
Brodie J RichardsHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0003-4081-794X
Roberto C Harris-MostertHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0009-0006-3445-2496
Katie E WagarHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0009-0002-2893-8626
Leonidas G IoannouDepartment of Automatics, Biocybernetics and Robotics, Jožef Stefan Institute, Ljubljana, Slovenia.ORCID 0000-0001-5460-8167
James J McCormickHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0003-2729-2077
Robert D MeadeHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0001-5922-4082
Emily J TetzlaffHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0002-4192-474X
Ronald J SigalHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0001-8324-717X
W Shane JourneayDepartments of Medicine and Community Health and Epidemiology, Dalhousie Medicine New Brunswick and Dalhousie University, Saint John, New Brunswick, Canada.ORCID 0000-0001-6075-3176
Glen P KennyHuman and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.ORCID 0000-0001-8683-6973

Funding

This project was funded by the Workplace Safety and Insurance Board (Ontario). The provision of grant support by WSIB does not in any way infer or imply endorsement of the content by the WSIB (funds held by G.P.K.). G.P.K is supported by a University of Ottawa Research Chair. F.K.O. was supported by a Mitacs Accelerate Post-Doctoral Fellowship Award. E.J.T. was supported by a Mitacs Accelerate Doctoral Fellowship Award.
6 · The paper itself

Abstract

rationaleIndustry guidelines recommend work-rest schedules to prevent unsafe core temperature elevations (> 38.0°C or > Δ1.0°C above baseline resting) in an "average" worker exposed to occupational heat stress. While permissible initial work durations (initial stay times [IST]) before implementing rest schedules have been suggested, existing data are limited to moderate-intensity efforts.

objectivesThe objective of this study was to assess whether factors of sex and age influence IST during heavy-intensity work.

methodsWe assessed work durations before reaching unsafe core temperature thresholds (i.e., > 38.0°C or > Δ1.0°C above baseline resting) among young (18-30 years) and older (50-69 years) males and females during simulated heavy-intensity work at 26°C, 29°C, and 32°C wet-bulb globe temperatures (WBGT).

findingsThe likelihood of surpassing a core temperature of 38.0°C significantly increased at 32°C WBGT (hazard ratio [95% confidence interval]: 2.0 [1.5, 2.7], p = 0.001), but not at 29°C WBGT (1.1 [0.9, 1.4], p = 0.342), compared to 26°C WBGT. Median (interquartile range) durations to reach 38.0°C across groups were 32 (23-52), 29 (23-47), and 26 (18-35) minutes at 26°C, 29°C, and 32°C WBGT, respectively. The likelihood of reaching Δ1.0°C above baseline resting significantly increased at both 32°C (3.8 [2.6, 5.4], p < 0.001) and 29°C WBGT (1.5 [1.1, 2.0], p < 0.001), with median durations being 55 (40-82), 42 (35-56), and 33 (29-42) min, respectively. Older females were more likely to reach 38.0°C (2.4 [1.3, 4.3], p = 0.004) and Δ1.0°C above baseline resting (2.5 [1.4, 4.7], p = 0.003) compared to young males. No other sex- or age-related differences were detected (p > 0.145). IMPACT: These findings highlight the heightened vulnerability of older females during heavy-intensity occupational heat stress, emphasizing the need for tailored guidelines to ensure equitable workforce protection.

Indexed as

Heat Stress DisordersHot TemperatureOccupational DiseasesOccupational ExposureRestAdolescentAdultAgedAge FactorsFemaleHumansMaleMiddle AgedSex FactorsTime FactorsYoung Adultageheat lossoccupational heat stresssexthermoregulation

Identifiers

PMID40903437
PMCPMC12512097

What OpenQuestion holds

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LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.