What is the difference between HEPA and negative pressure rooms?

This article gives a brief about HEPA filter, Negative pressure room and Positive pressure room. These are normally applicable for hospitals, isolation wards, infectious disease centres etc.

HEPA filters for hospitals and clinics

The HEPA filter is a filter fixed in the HVAC system. There are also HEPA filtering machines. These machines simply circulate air within the room after cleaning. The HEPA filter is capable of filtering microorganisms including most of the viruses. HEPA filter cleans entire dust from the air too. So HEPA filter is basically an air cleaning filter.

Negative Pressure rooms for isolation rooms in hospitals

Negative Pressure isolation rooms are rooms in hospitals having negative pressure. There are negative pressure rooms and positive pressure rooms in hospitals. Negative pressure is slightly lower than the atmospheric pressure. As an example, the corridor of a hospital will be at normal atmospheric pressure. A negative pressure room such as isolation room will have slightly lower pressure than the corridor. Suppose there is a patient with Corna Virus (COVID19) in the isolation room. The air in the room will have COVID19 viruses. This air should not go to the corridor. If it reaches the corridor, somebody else will catch the infection too.

Since the pressure in the Negative pressure isolation room is lower than the corridor, air will not escape to the corridor at all. The air will go out of the room through an HVAC system fitted with HEPA filters.

Positive pressure rooms for hospitals and clinics

Central sterile services department rooms (CSSD) are normally having positive pressure rooms. These are exactly opposite to Negative pressure rooms. A CSSD room stores all sterile items. Hence it is essential that pathogens do not enter this room. Suppose there are pathogens in the air in the corridor including COVID19. This should not enter the sterile room. Hence the CSSD room is at a slightly higher pressure than the corridor. This means that air will not enter into the CSSD room from the corridor. Air will only flow out of the positive pressure room. Hence the contaminated air from the corridor or other rooms will not enter CSSD rooms.

We are providing various HEPA cleaning equipment, Negative pressure rooms and positive pressure rooms. Also, we provide monitoring systems for negative pressure monitoring and positive pressure monitoring. These monitoring systems are with negative pressure alert systems.