FIELD STUDY ON THERMAL COMFORT OF OFFICE WORKERS: INTEGRATION OF MEASURED DATA AND OCCUPANT PERCEPTIONS

Year 2026, Volume: 11 Issue: 1, 89 - 107, 10.01.2026

Koray Sandal , Nadir İlten

Abstract

Thermal comfort is a critical parameter affecting employee productivity, health, and workplace safety. Ensuring appropriate thermal conditions in work environments is essential for improving performance and maintaining sustainable working conditions. In this study, a comprehensive evaluation of thermal comfort conditions was performed at the Department of Technical Works (Fen İşleri Dairesi Başkanlığı) of Balıkesir Metropolitan Municipality, using both physical measurements and occupant surveys across different seasons (summer, winter, spring, and autumn). Indoor environmental variables—air temperature, relative humidity, air velocity, and mean radiant temperature—were measured with a Testo-480 device, and the corresponding PMV (Predicted Mean Vote) and PPD (Predicted Percentage of Dissatisfied) indices were calculated. Concurrently, surveys were administered to the employees to obtain AMV (Actual Mean Vote) and APD (Actual Percentage of Dissatisfied) values. By comparing objective measurement results with subjective survey responses, the consistency between technical data and the occupants’ thermal perceptions was analyzed.
The findings indicate that although the measured thermal parameters in summer fell within standard comfort ranges, the employees perceived the environment as “slightly warm.” In winter, the measurements suggested comfortable conditions, yet many employees described the environment as “slightly cool.” In spring and autumn, measurements and perceptions were generally in agreement; however, significant differences in thermal sensation emerged based on factors such as gender, age, and clothing insulation (clo) levels. Employees with lower clo values tended to report higher discomfort, whereas those with greater clothing insulation exhibited notable discrepancies between measured and perceived comfort. Overall, variations in clothing insulation were found to shift the optimum comfortable working temperature by about 0.9–2.5 °C.
These results underscore the necessity of continuous monitoring and improvement of thermal comfort conditions in municipal service buildings and similar workplaces to ensure both employee satisfaction and operational efficiency.

Keywords

thermal comfort , public building , survey , PMV-PPD

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