The health industry is a very large and special industry, and it has high requirements for air cleanliness. Typically, the minimum requirement for hospital air is filtered using a combination of a 30% efficiency prefilter and a 90% efficiency final filter. HEPA high efficiency filter filtration is generally not required, but HEPA filter filtration is required in special cases such as isolation chambers, specific test and care areas.
Many HVAC systems in hospitals use 100% outdoor air, which is a good strategy to prevent patients from cross-infecting suspended microorganisms in HVAC systems. However, 100% use of outdoor air does not eliminate the growth of microorganisms in air filtration media and its adverse effects on the care environment. Therefore, many hospitals still need advanced HVAC systems.
The clean room of the health system was first used in the operating room. At first it was only widely used in orthopedic surgery because orthopedic surgery is prolonged and prone to infection. The level of control is ideally achieved with an air cleanliness level of 100 near the operating table. It is generally recommended to use a top HEPA filtration system that covers an area of at least 3 m × 3 m to include the operating table and the person.
Other areas in which cleanrooms are used include birthing rooms, nursery rooms, burn rooms, and heart disease care units. One of the latest developments is the use of cleanrooms for dental surgery, which reduces the risk of infection of medical personnel during long-term surgery.