[Thermal comfort and indoor air quality in some workplaces of the Polizia di Stato (State Police) in Italy]

Introduction. Little can be found in the literature about thermal comfort and indoor air quality (IAQ) in law enforcement workplaces. This study, based on environmental surveys carried out by the Centro Sanitario Polifunzionale of Milan (Italian State Police Health Service Department), aims to assess the thermal comfort and IAQ in some of the Italian State Police workplaces. Materials and methods. Measurements were performed in some indoor workplaces such as offices, archives, laboratories and guard-houses in various regions (Lombardia, Emilia Romagna, Liguria, Veneto, Trentino Alto-Adige) of Northern Italy. The PMV/PPD model developed by Fangar for the evaluation of the thermal comfort was used. We measured both CO2 concentration and relative humidity indoor levels for the evaluation of IAQ. We used Chi square and t Student tests to study both prevalence of thermal discomfort and low IAQ, and their differences between summer and winter.Results. For the purposes of the present study we carried out 488 measurements in 36 buildings (260 in winter and 228 in summer). Our results showed that thermal comfort was reached in 95% and 68% of environmental measurements (in winter and summer, respectively). In summer, we measured different types of thermal discomfort (it was almost always ranged ‡0,7<PMV < or 1<PMV<2). As regard to IAQ, CO2 exceeded the threshold limit value (1000 ppm) in 39% (winter) and 9% (summer) of our measurements. Chi-square test showed a statistically significant difference (p<.0001) between summer and winter for all outcomes considered. Indeed, thermal comfort was better in winter than summer (X} = 61.0795), while IAQ was found to be better in the summer than winter considering both the CO2 1000 ppm and 1200 ppm threshold values (X} = 56.9004 and X? = 8.8845 respectively, p<.0001). Prevalence of low relative humidity (RH<30%) in winter was higher than in summer (X} = 124.7764, p<.0001).Conclusions. Even though this study did not report any situation of risk to Italian police officers health and safety, it has highlighted some potential issues in some of the examined workplaces, concerning thermal comfort in summer and IAQ in winter. Regarding the risk assessment process, simple and inexpensive preventive measures are already feasible in the 'observation phase' of the risk assessment, before execution of instrumental environmental survey. According to the technical standards and risk assessment models, this way might increase both comfort levels for workers employed in indoor environments and the effectiveness of the risk assessment process, through the optimization of available resources.