Temperature and humidity control in operating theatres: BMS vs. Thermostat systems

Abstract

Maintaining proper temperature and humidity in operating theatres (OTs) is essential for infection control, patient safety, and equipment performance. This study examines the effectiveness of environmental monitoring and control practices in Sri Lankan hospitals, comparing building management system (BMS)-enabled facilities with traditional thermostatically controlled settings. Although international standards such as ASHRAE 170 recommend temperatures of 20–24°C and relative humidity of 40–60%, implementation is inconsistent. A multi-case study approach was used, involving two BMS-enabled and two non-BMS hospitals. Findings show that although BMS systems enable real-time monitoring, issues such as delayed responses, threshold deviations, and energy saving compromises impact compliance. Non-BMS setups lack centralized monitoring, rely on inconsistent manual adjustments, and offer limited transparency. Common challenges across all scenarios include technical errors, limited staff awareness, and behavioural impacts such as frequent door openings and comfort-based overlaps. The study highlights the need for targeted strategies across both system types. Key recommendations include staff training, engineering-clinical collaboration, visual compliance indicators, and adoption of IoT-based monitoring in non-BMS environments. This research addresses a gap in OT environmental management in Sri Lanka and suggests practical, system-specific solutions to improve safety and compliance.