As an important yet special public building, hospitals and healthcare are densely populated and have variety of functional partitions, such as operating rooms, ICU and inpatient ward, and therefore have different requirements for parameters of cleanliness, air speed, air pressure, temperature and humidity. Due to the particularity of medical services, air conditioning systems need to operate without interruption. The design of HVAC in hospital is not only about providing a comfortable environment, but more importantly, about effectively controlling cross-contamination and ensuring the safety of people in the hospital.