Isolation Rooms

Air pressure in a given room under positive pressure is higher than outside, so contaminants (particles, viruses, bacteria, gases, etc.) are kept out. The pressure differential should be at least 2.5 Pa and ideally should be 8 Pa. These positive pressure isolation rooms are also often known as protective rooms.  

With our high-performance hospital air filtration units and accessories, a flexible installation of both negative and positive pressure environments can be created in the most cost-efficient way. These negative and positive pressure systems can also be quickly moved from one patient location to another as needs change.

Setting up a positive or negative pressure isolation environment is an effective way of creating an isolation room and has many applications in healthcare and in industries like microelectronics – in fact, in any situation where cleanliness is a priority.

In a positive or negative pressure isolation room, air flow is controlled so it always flows from less to more contaminated areas. Control is achieved by adjusting the pressure differential between supply and exhaust air.

Positive Pressure Environment

Air pressure in the room under positive pressure is higher than outside, so contaminants (particles, viruses, bacteria) are kept out. This is done by ensuring that the exhaust air is run 10-15 per cent lower than the supply air. The pressure differential is more than 2.5 Pa and ideally should be 8 Pa. The positive pressure environment is used to protect patients in operating theatres so that infection does not enter open body cavities and to protect patients with HIV infection, or other conditions linked to a compromised immune system, being nursed in isolation rooms.

Positive pressure rooms are also important in medical research where the particulate count in the environment has to be extremely low in order to preserve the integrity of the testing process. A positive pressure isolation room is also often known as a protective room.

The air pressure in the room under negative pressure is lower than outside so that contaminated air from the room does not flow out into surrounding areas. The pressure differential should be greater than 2.5 Pa. The air exiting any negative pressure environment should be filtered with an IQAir H13 high-efficiency filtration unit to remove viruses and bacteria.

Negative Pressure Environment

The air pressure in the room under negative pressure is lower than outside so that contamination from the room does not flow out into surrounding areas. Exhaust air is run 10-15 per cent higher than the supply air. The pressure differential should be greater than 2.5 Pa. The negative pressure environment is used to protect others from patients being nursed in isolation rooms because they have a very contagious disease (e.g. TB). The air exiting a negative isolation room should be filtered with a high-efficiency particulate air (HEPA) filter to remove viruses and bacteria.

For positive and negative pressure isolation rooms to work most effectively, there are a number of other factors to be considered:

• The air entering the room should be filtered with a HyperHEPA filter
• There should be 12 or more room air changes per hour
• The door of the isolation room should be self-closing
• Windows, floors and ceilings should all be well sealed
• Fans and other components should be well maintained
• In-line monitoring of pressures is essential

There should be an ante-room between the negative or positive pressure isolation room and the corridor/surroundings to provide a controlled environment for donning and taking off protective clothing and delivering equipment.

The idea of positive and negative pressure isolation rooms is not new, but modern developments have meant that the technology is much more widely available. One of the reasons for this is that complicated and expensive air handling systems are no longer the only choice – the same results can be achieved with much simpler systems that offer a more impressive price-to-performance ratio.

Commercial Air Filtration can help you to build positive or negative pressure isolation rooms using the most effective and reliable filtration technology available. One of our most popular products for hospitals and clean room environments is the IQAir Cleanroom H13 air cleaner which when used with the IQAir InFlow or IQAir OutFlow attachments creates localised either negative or positive pressure isolation rooms.

The idea of positive and negative isolation rooms is not new, but modern developments have meant that the technology is much more widely available. One of the reasons for this is that complicated and expensive air handling systems are no longer the only choice – the same results can be achieved with a system that is much more user-friendly and offers a more impressive price-to-performance ratio.

Commercial Air Filtration can help your hospital to deploy positive or negative isolation rooms using the most effective and reliable filtration technologies available.

Tuberculosis (TB) is the single most deadly disease known to man. Approximately 1.7 billion people are infected with the disease worldwide, representing nearly one-third of the world's population.

It is recognised that the greatest risk of TB transmission exists with undiagnosed TB cases. A complete program to control TB must include engineering controls to reduce the concentration of infectious droplet nuclei in the air.

TB isolation rooms – fixed vs. mobile installation

Because the airflow requirements for TB Isolation Rooms are much greater than the requirements for other patient spaces, most facilities will find it necessary to provide new supply and exhaust air systems to serve the isolation rooms.

Many healthcare institutions dedicate the exhaust air system to serving only isolation rooms. Fitting a dedicated supply and exhaust duct network into an existing facility typically causes many problems for a designer. Obstructions of other building services in ceiling cavities often require the supply and exhaust ductwork to transition and turn many times between the air handling equipment and the room air terminals.

It is essential that the effect of these transitions and turns is considered when sizing fans for supply and exhaust air systems. Frequently, the installing contractor will decide to take a different route for the ductwork than intended by the designer, and the modified route will increase resistance to airflow.

All these issues can be avoided by the use of mobile IQAir high-performance air filtration units fitted with inflow and outflow adaptors – giving all the benefits of a major installation without the disruption, cost, or ongoing maintenance issues.