Numerical investigation of indoor air quality in health care facilities: A case study of an intensive care unit

The risk of healthcare-associated infections (HAIs) is higher in patients admitted to intensive care units (ICU) and high dependency units (HDU). Currently, most ventilation studies focus on specialized areas, mainly isolation rooms and operating rooms. This paper focuses on the ventilation of multiple-bed hospital wards in developing countries. This study uses computational fluid dynamics (CFD) simulation to model and investigate airflow and the spread of pollutants. The study aims to investigate ICUs with various ventilation system designs. These predicted behaviors and characteristics were compared numerically to determine compliance with the requirements of airflow patterns, airborne contaminant distribution, and current international standards. The case study simulations were carried out using ANSYS Fluent simulation software as a solution tool. Three different ventilation systems, Vertical Laminar Airflow Ventilation (VLAF), Horizontal Laminar Airflow Ventilation (HLAF), and Temperature-Controlled Airflow Ventilation (TcAF), were modeled within five different designs to determine the most effective possible distribution of air inside the patient's room, based on different categories, primarily temperature distribution, CO2 concentration, and airflow distribution. The authors applied the TcAF technique in an ICU room, comparing the results of the proposed technique with those of other common techniques (HLAF and VLAF). It was found that TcAF showed the most effective airflow distribution around patients, isolating each patient from the others. However, the temperature distribution was excluded from the ASHRAE standard. HLAF with two exhausts is the most suitable option, with a lower CO2 concentration than the alternatives and a temperature that meets ASHRAE standards.

Automated summary

This study investigates the ventilation in multiple-bed hospital wards in developing countries, using computational fluid dynamics simulation. Three ventilation systems, VLAF, HLAF, and TcAF, were compared in terms of airflow distribution, CO2 concentration, and temperature distribution. The results showed that TcAF had the most effective airflow distribution, but did not meet the ASHRAE standard for temperature distribution. HLAF with two exhausts was found to be the most suitable option, with low CO2 concentration and temperature compliance with the ASHRAE standard.