Mental Fatigue Assessment in Different Thermal Environments – Protocol

Emília Quelhas Costa; João Santos Baptista; Jorge Carvalho

Emília Quelhas Costa Faculty of Engineering, University of Porto
João Santos Baptista Faculty of Engineering, University of Porto
Jorge Carvalho Faculty of Engineering, University of Porto

Keywords: EEG; Mental Fatigue; Thermal Environnement; Fatigue Indexes

Abstract

Environmental and personal characteristics influence the behavior of individuals through the limitation of effort levels by a more or less rapid induction of fatigue. In particular, mental
fatigue is recognized as a major cause of errors leading to accidents. As a consequence, thermal environment study has gained increasing importance in recent years. In order
to contribute to enlarge the knowledge in this field, this work aims to present an essay protocol to evaluate the influence of the thermal environment on mental fatigue, based on
electroencephalographic (EEG) analysis. With this purpose an exploratory study was held with 36 volunteers to validate the protocol. Volunteers simulated an administrative task for
one hour. Fatigue assessment was carried out by analyzing Alpha and Beta waves amplitude over time. Assays were performed in a climatic chamber with controlled temperature and
humidity: 22°C (40 and 80% RH) and 32°C (40 and 80% RH). Results suggest that both temperature and humidity influence the amplitude of the EEG signal (Alpha and Beta
waves) in both hemispheres. The greatest amplitudes were found whenever environmental temperature and/or relative humidity values were higher. At the end of the article the
advantages and limitations of mental fatigue assessment are discussed.

Author Biographies

Emília Quelhas Costa, Faculty of Engineering, University of Porto

Associated Laboratory for Energy, Transports and Aeronautics (LAETA), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.

Pos-Doc researcher at Faculty of Engineering, University of Porto.

Member of the research Group on Prevention of Occupational and Environmental Risks of LAETA.

Occupational hygiene, thermal environment, fatigue.

João Santos Baptista, Faculty of Engineering, University of Porto

Associated Laboratory for Energy, Transports and Aeronautics (LAETA), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.

Master Course Director (Master in Occupational Safety and Hygiene Engineering).

Assistant Director (Doctoral Program in Occupational Safety and Health.

Head of the research Group on Prevention of Occupational and Environmental Risks of LAETA.

Associated Professor at Faculty of Engineering, University of Porto.

Occupational safety and health, ergonomics, risk assessment, mining safety.

Jorge Carvalho, Faculty of Engineering, University of Porto

Centre for Natural Resources and the Environment (CERENA), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.

Assistant Professor at Faculty of Engineering, University of Porto.

Geophysics, statistics, signal treatment, human behavior.

References

Available in the full article.