Mitigating heat effects in the workplace with a ventilation jacket: Simulations of the whole-body and local human thermophysiological response with a sweating thermal manikin in a warm-dry environment

Simona Del Ferraro; Tiziana Falcone; Marco Morabito; Michela Bonafede; Alessandro Marinaccio; Chuansi Gao; Vincenzo Molinaro

doi:10.1016/j.jtherbio.2023.103772

Mitigating heat effects in the workplace with a ventilation jacket: Simulations of the whole-body and local human thermophysiological response with a sweating thermal manikin in a warm-dry environment

J Therm Biol. 2024 Jan:119:103772. doi: 10.1016/j.jtherbio.2023.103772. Epub 2023 Dec 17.

Authors

Simona Del Ferraro¹, Tiziana Falcone², Marco Morabito³, Michela Bonafede⁴, Alessandro Marinaccio⁵, Chuansi Gao⁶, Vincenzo Molinaro⁷

Affiliations

¹ Laboratory of Ergonomics and Physiology, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Via Fontana Candida 1, 00078, Monte Porzio Catone, Rome, Italy. Electronic address: s.delferraro@inail.it.
² Laboratory of Ergonomics and Physiology, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Via Fontana Candida 1, 00078, Monte Porzio Catone, Rome, Italy. Electronic address: t.falcone-sg@inail.it.
³ Institute of BioEconomy (IBE), National Research Council, Via Madonna Del Piano 10, 50019, Sesto Fiorentino, FI, Italy; Centre of Bioclimatology, University of Florence, Piazzale Delle Cascine 18, 50144, Florence, Italy. Electronic address: marco.morabito@ibe.cnr.it.
⁴ Laboratory of Occupational and Environmental Epidemiology, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Via Stefano Gradi 55, 00143, Rome, Italy. Electronic address: m.bonafede@inail.it.
⁵ Laboratory of Occupational and Environmental Epidemiology, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Via Stefano Gradi 55, 00143, Rome, Italy. Electronic address: a.marinaccio@inail.it.
⁶ Aerosol and Climate Laboratory, Division of Ergonomics and Aerosol Technology, Department of Design Sciences, Faculty of Engineering, Lund University, Sölvegatan 26, Lund, Sweden. Electronic address: chuansi.gao@design.lth.se.
⁷ Laboratory of Ergonomics and Physiology, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Via Fontana Candida 1, 00078, Monte Porzio Catone, Rome, Italy. Electronic address: v.molinaro@inail.it.

PMID: 38145612
DOI: 10.1016/j.jtherbio.2023.103772

Abstract

Climate change is increasingly affecting human well-being and will inevitably impact on occupational sectors in terms of costs, productivity, workers' health and injuries. Among the cooling garment developed to reduce heat strain, the ventilation jacket could be considered for possible use in workplaces, as it is wearable without limiting the user's mobility and autonomy. In this study, simulations with a sweating manikin are carried out to investigate the effects of a short-sleeved ventilation jacket on human thermophysiological responses in a warm-dry scenario. Simulations were performed in a climatic chamber (air temperature = 30.1 °C; air velocity = 0.29 m/s; relative humidity = 30.0 %), considering two constant levels of metabolic rate M (M₁ = 2.4 MET; M₂ = 3.2 MET), a sequence of these two (Work), and three levels of fan velocities (l_f = 0; l_f=2; l_f=4). The results revealed a more evident impact on the mean skin temperature (T_sk) compared to the rectal temperature (T_re), with significant decreases (compared to fan-off) at all M levels, for T_sk from the beginning and for T_re from the 61^st minute. Skin temperatures of the torso zones decreased significantly (compared to fan-off) at all M levels, and a greater drop was registered for the Back. The fans at the highest level (l_f=4) were significantly effective in improving whole-body and local thermal sensations when compared to fan-off, at all M levels. At the intermediate level (l_f=2), the statistical significance varied with thermal zone, M and time interval considered. The results of the simulations also showed that the Lower Torso needs to be monitored at M₂ level, as the drop in skin temperature could lead to local overcooling and thermal discomfort. Simulations showed the potential effectiveness of the ventilation jacket, but human trials are needed to verify its cooling power in real working conditions.

Keywords: Cooling garments; Heat stress; Occupational heat strain; Sweating manikin; Thermophysiological response; Ventilation jacket.

MeSH terms

Body Temperature Regulation* / physiology
Hot Temperature
Humans
Manikins
Respiration
Skin Temperature
Sweating*
Working Conditions
Workplace