Evaluating the effective environmental factors on the satisfaction of patients and companions with the patient’s rooms in Tehran hospitals

Various studies confirm that indoor environmental quality (IEQ) evaluation plays an important role in health, wellbeing, and satisfaction, especially in healthcare facilities. Moreover, these building types are among the major energy consumers. The variety of the users’ requests (patient, patient companion, and staff), physiological conditions, and mental sensitivities increase the importance of choosing the appropriate method of studying healthcare buildings. Previous studies have suggested many methods for assessing indoor environmental quality. Recent research has found IEQ to be largely influenced by thermal comfort, acoustic comfort, lighting comfort, and indoor air quality. Also, due to the differences in users’ perceptions of the limits set in the relevant standards and conditions in hospitals, questionnaires were used to compare the users’ satisfaction with standards and real situations. The main purpose of this study is to evaluate the quality of the patient’s room indoor environment in order to identify the most important indoor quality indices affecting user satisfaction and compare environmental conditions with existing standards such as American Society of Heating, Refrigerating and Air-Conditioning Engineers (Ashare) standard, world health organization (WHO), Iran standards, etc. in this field. In this regard,  physical measurements data of environmental parameters affecting the quality of the indoor environment in medical centers were collected. Then by comparing the results obtained from the users’ questionnaires and physical measurements with related standards and previous research, the most important factor influencing indoor environment quality in patient’s room is identified. Finally, the relationship between the type of users who are separately affected by indoor conditions is expressed.

In the current study, based on the results of previously validated studies, the physical data and users’ satisfaction levels are measured via questionnaires to assess the hospitals’ indoor environment quality. Indoor environment quality evaluation is generally studied using the four main characteristics of thermal, lighting, acoustic, and indoor air quality. Five hospitals in Tehran have been selected, and their IEQ has been evaluated. In this regard, 482 questionnaires were completed by the patients and their companions. In these questionnaires, four indices mentioned above, out of the total indices affecting indoor quality, were evaluated. At the same time, these indices have been compared using environmental characteristics such as dry air temperature, relative humidity, lighting intensity, and sound level intensity, carbon dioxide concentration (CO2), fine particulate matter smaller than 2.5 micrometers (PM 2.5) concentration by the researcher, simultaneously with the completion of the questionnaire by users under specific protocols.

Based on the results, the highest compliance with the standard was observed in indoor air quality (IAQ) and the lowest in sound quality according to the World Health Organization (WHO) standards. The results show that there is a significant correlation between the thermal and optical indices concerning indoor quality, which are 0.59 and 0.42, respectively. However, the two indices of acoustic quality and IAQ, despite their high correlation with indoor quality  (0.62 and 0.67, respectively), have an internal source. Comparing the frequency of case samples within the standard temperature range (23-26°C) with other cases shows an 11% increase in user dissatisfaction due to non-compliance with this range.

Although the acoustic quality of most case samples is out of standard, 30 to 40% of users have reported usual satisfaction with the sound condition. Due to the excess of standard lighting intensity in most case samples, lighting quality has maintained the average level of user satisfaction at the highest level. Also, comparing the results of the users’ satisfaction in the questionnaire with the standard range of the four indoor environmental quality indices stated 100% compliance with indoor air quality, 68% with thermal status, and 18% with lighting status. The results also showed that acoustic status had no significant relationship with standard range and user satisfaction conditions. Also, the dry air temperature factor in evaluating thermal quality is more effective than the relative humidity. Based on the data collected from the statistics, a statistical model is presented to identify the general users’ satisfaction with IEQ based on environmental parameters.