Stop COVID-19 From Spreading – Isolation Room Safety

Isolation Room Basics

Isolation rooms are controlled, critical environments in hospitals. When patients have communicable diseases like COVID-19, they are normally placed in one of these isolation rooms. Isolation rooms achieve their effectiveness in controlling contagious disease by keeping internal room pressures lower that areas outside of the room, thus keeping all of the ‘bad stuff’ inside the room. It is easy to determine that a room is a negative pressure room by opening the door.  If the door of negative pressure room is opened a rush of air enters the room. This happens because areas of higher pressure (i.e. areas outside of the isolation room) will naturally move to areas of lower pressure (i.e. the isolation room interior).

The function if the room is simple; if air rushes in, when a doctor or nurse enters to treat the affected patient, theoretically no infected air from within the patient room can escape through an open door.

More protection needed

Most hospitals already have some isolation rooms. Recently, however, hospitals have become overwhelmed with cases of COVID-19 (Coronavirus), and they are in need of additional isolation rooms.  This has led to creating temporary isolation rooms to maintain the safety by protecting caregivers, patients, doctors, nurses, and the general public.  Although creating these negative pressure rooms is simple in theory it is sometimes difficult to achieve.

A critical aspect of maintaining correct pressures of an isolation room is the ability to monitor the actual negative pressure differential.  It is not enough to determine whether a room is a negative pressure room by opening the door and feeling the air from the hall flow into the room.  It is crucial to use some form of instrumentation. In years past, many hospitals turned to a device known as a “Ball In The Wall” or a “Ball In Tube” pressure indicator. These simple devices can be easily understood and implemented. They consist of a ball inside of a tube. Theoretically, when there is higher or lower pressure on a side of the tube protruding a wall, the ball “moves” from a direction of lower pressure to higher pressure, providing a visual indication of the pressure.

These work okay for general applications but fall very short when trying to control serious pandemic-scale diseases like COVID-19.

Here are some of the major downfalls of using “Ball In The Wall” pressure indicators for monitoring room pressure in isolation rooms.

  1. There is no way to determine the actual room pressure. Negative-pressure isolation rooms are required to maintain a minimum of  0.01-inch WC negative-pressure differential1 to the adjacent corridor whether or not an anteroom is utilized to keep communicable disease like COVID-19, SARS, H1N1, etc. under control. A simple Ball In Tube cannot display the actual differential air pressure. It can only indicate that there is some pressure differential present.
  2. No advanced alert system. Unlike more sophisticated systems and instruments, a simple ball in the wall can’t warn critical caregivers in advance if pressure in the isolation room is changing, indicate how much it has changed, or when it changed. Additionally, unlike more complete systems, the ball in the wall can’t notify staff by email, SMS, local alarm or other methods if the required pressure is not maintained.
  3. Another shortfall is the inability for a ball in a tube to report historic data conditions; i.e. when the room started gaining pressure, how long and at what tie the pressure was dangerous, etc… It does not log any pressures.

While these may sound optional, they are critically important attributes that any isolation room should have. Ultimately, it is what will help to stop the spread of COVID-19.

Why are Hospitals Still Using Ball In Wall Pressure Indicators?

Interestingly enough, some of the most technologically advanced hospitals are using these antiquated ball in tube systems to monitor pressure in isolation rooms, surgical rooms, and other critical environments.

One theory for their continued use is the simple fact that because everyone else is using it, it does not matter if it is effective, safe, or even functional. As long as it is widely accepted, then no one can be blamed if something goes wrong. Another theory, is that many “isolation rooms” are not actually maintaining negative pressure at the levels specified by overseeing compliance organizations.  This could be a case of “if I don’t know about it, I am not responsible for it.”

It could be said that many hospitals would have to spend a great deal of money to repair faulty equipment and modernize isolation rooms if they were to become aware of the true air pressure in these hospital rooms. When using ball in the wall type pressure indicators, there is a “yes/no” passing grade. Either the ball is visible or it isn’t. The margin for error is huge. The ball may indicate there is in fact some level of negative or positive pressure, but how much? It is near the threshold of leaving the room vulnerable and completely exposed to the public? It could be. Unfortunately, with the ball in the wall – there is no way to know for sure.

Unlike the ball in the wall indicators there are now modern pressure instruments that are calibrated with NIST traceability. This begs the question, “Just how accurate can mass produced ping-pong balls inside a plastic tube be?” Would you trust your patient’s lives or the health and safety of the public on a ball in a tube?

In short, it is a matter of public safety. In many hospitals, a ball in a tube is the only safeguard between a patient infected with a communicable disease like COVID-19 and the health and welfare of the public.

Better solutions

What are hospitals to do? Fortunately, there are many other instruments available which account for all of the holes and gaps in protection the ball in the wall fails to offer. In fact, many of these instruments cost much less and offer considerably more. In a logical world, the answer would be simple, get rid of the outdated and antiquated ball in the wall, and upgrade.

However, deeply ingrained processes and practices must be overcome. Fear of change and technological advance may paralyze the decision making process, even if it is for the betterment of the patient and the public as a whole.

We at Two Dimensional Instruments, LLC are providing hospitals with special pricing and support for our isolation room monitoring instruments through the deadly the COVID-19 outbreak. To learn more about what we can do for your hospital, please contact us or call 877-241-0042


1 Planning and maintaining hospital air isolation rooms
Controlling the spread of infectious diseases is essential to maintaining a safe care environment