Evaluation of HVAC Design Parameters in High-Performance Hospital Operating Theatres

Abstract

Unidirectional flow air-conditioning systems are suitable for achieving indoor air quality required in high-performance operating rooms (organ transplants, cardiac surgery, aorta, orthopedic, burns, etc.). This paper analyzes indoor environmental conditions and technical and hygienic requirements for the design of heating, ventilation, and air-Conditioning (HVAC) systems for high-performance operating theatres. The main standards applicable to this type of operating rooms were compiled. Standard UNE 100713:2015, ASHRAE Standard 170-2017, and the European pre-norm EN 16244 were analyzed. A case study shows the lack of uniformity in design criteria and their ranges of values, which generates different design approaches. It was concluded that using these standards applicable to high-performance operating rooms leads to very different indoor environmental conditions for patients and medical personnel—air velocity profiles, air movement pattern, temperature, relative humidity gradients, and pressure stratification. Computational fluid dynamics (CFD) studies have been shown to detect areas of haven that favor microbiological load accumulation. In this way, it is possible to define cleaning protocols to attend these anomalies in a preventive way.

The Influence of Surgical Staff Behavior on Air Quality in a Conventionally Ventilated Operating Theatre during a Simulated Arthroplasty: A Case Study at the University Hospital of Parma

“…In particular, there was a strong relationship between the ventilation system, its air flow scheme, and staff behavior, and the air motion and air temperature field in high-performance hospital OTs equipped with HVAC systems with unidirectional and turbulent flow. Therefore, the need for training and control of surgeon/medical and nursing staff should be emphasized [25,28,32,35,47].…”

“…Different studies showed the strong influence of the amount of people present in the OT and their movements and the influence of doors opening and closing on microbial contamination, air pressure, and microclimatic conditions. Furthermore, surgical staff behavior has a strong impact on indoor air quality and ventilation effectiveness in OTs equipped with HVAC systems with unidirectional turbulent flow [22][23][24][25][26][27][28][29][30][31][32][33][34][35]. In particular, the ISChIA study [22,36] showed a correlation between the number of times the door was opened, the number of people in the OT, and microbial air contamination, highlighting a high level of contamination that exceeded the current threshold values in OTs supplied with unidirectional airflow, which was even higher than the microbial contamination values obtained in conventionally ventilated OTs in some case4s.…”

Assessing the Energy Demand Reduction in a Surgical Suite by Optimizing the HVAC Operation During Off-Use Periods

“…In addition, it is necessary to maintain temperature and humidity within determined values that avoid the proliferation of bacteria, viruses and fungi, while providing the most comfortable working conditions possible for the surgical personnel [27][28][29]. However, hygrothermal and ventilation requirements in ORs may significantly vary depending on the standard considered for designing the HVAC equipment, as different countries define their own technical guidelines [30][31][32]. A detailed comparative of different standards can be found in [21].…”

Application of Predictive Maintenance in Hospital Heating, Ventilation and Air Conditioning Facilities

“…Some pathologies require specific environmental needs in order to favor their improvement and/or avoid their transmission to medical personnel and other patients (nosocomial infections). Hospital heating, ventilating and air-conditioning (HVAC) installations are an effective tool in the fight against nosocomial infections [1], so providing adequate indoor environmental conditions in hospitals is intimately related to people's health.…”