Savings achieved in operating rooms by implementing ventilation air flow regulation strategies, in several climatic zones of spain

Abstract

Hospitals are critical environments, which are characterized by the health and safety of patients and staff. Hospitals have uninterrupted operation of the facilities, thus requiring air conditioning and ventilation, in order to reduce physical, chemical and biological contaminants, such as the current Covid-19. Hospitals have different indoor environments due to the different comfort and health needs of their occupants. These are defined according to the hospital's own standards for IAQ for each specialized area. Currently, most hospital ventilation studies revolve around specialized areas such as operating rooms and infectious and immunosuppressed wards, etc. However, the best practices for achieving an adequate indoor environment are not yet unanimously recognized. This study focuses on the reduction of energy, economic and environmental costs, all of them obtained when a ventilation flow strategy, ventilation controlled by demand, is installed in the operating rooms in a Hospital in Spain. The ventilation air flow rates required in operating rooms, according to Spanish standard UNE 100713, are very high when they are in operation (with a minimum flow rate of 2400 m3/h or 20 ren/h). However, the regulations also allow reducing the air flow during periods of inactivity of the operating room, as long as the safety, availability and asepsis are guaranteed. In this study, experimental data have been collected by monitoring the operation of the air conditioning and ventilation system, as well as the occupancy of the operating rooms of a 900-bed Spanish hospital. With all these acquired data, it has been possible to model the real operation mode of a standard operating room. Due to the implementation of this proposed model, it has been possible to study different ventilation airflow regulation strategies, with the aim of improving hospital IAQ in Spain, in three different climatic zones. The results obtained in operating rooms, through the implementation of the proposed strategy in ventilation, show that a good IAQ is achieved, reaching energy savings in heating, cooling and electricity consumption, between 20% to 70%. Therefore, the economic costs are drastically reduced, amortizing the investment required for the regulation and control system of the HVAC system in less than a year.