Evaluating the suitability of standard thermal comfort approaches for hospital patients in air-conditioned environments in hot climates

Hospital patients have the same thermal needs but disparate metabolic levels, and physical/medical conditions. However, the thermal environments of hospitals are often not designed with these distinctions in mind, nor with a particular focus on patients, but based rather on standard comfort methodologies more often used in offices. This paper seeks to confirm if a standard steady-state thermal comfort approach is inadequate, especially in hot climates. The research was conducted on 120 patients during the summer of 2017 in Jeddah, Saudi Arabia, with environmental monitoring of all thermal comfort parameters, alongside estimations of clothing insulation and activity levels for patients in the surgical and medical wards. The data was analysed using simple and multiple regressions, and measures of correlations tests to assess the reliability of the results in addition to t-tests for detecting the differences. The findings revealed a significant difference between the Thermal Sensation Vote (TSV, assessed by patient surveys), and the Predicted Mean Vote (PMV, assessed by physical measurement), with the TSV survey approach failing to identify a unique neutral temperature while the PMV revealed a neutral temperature of 25.6 degrees C. Importantly, the neutral temperature predicted by Griffith's method gave an extremely large range of results, form 16.2 degrees C-28.8 degrees C (mean = 22.7 degrees C; SD = 2.51). The corollary being that using PMV or a non-patient-specific temperature for hospital rooms is a poor idea. Given the known links between hospital environments and recovery outcomes, this result has implications for the design of hospital environments and the setting of national or international standards.