How to convert an existing room into a negative pressure, isolation room?

//How to convert an existing room into a negative pressure, isolation room?

Conversion of a room into a negative pressure room is mainly required for hospitals, clinics, research centers, laboratories etc.

Vacker LLC has been in the field of pressure control and monitoring for several years. We have a strong customer base of hospitals, clinics, and public health authorities in over 30 countries worldwide.

When it comes to converting your existing room into a negative pressure room, finding a qualified service provider can be daunting as there is not enough information on the web. With millions of people affected with the coronavirus, a sudden need to create isolation rooms is being felt globally. We decided to share our views for our readers and customers to help convert their existing room into a negative room quickly.

What is a negative pressure, isolation room?

A negative pressure room is an isolated room with a pressure lower than that of its surroundings. It does not allow air present inside the room to escape to other areas which are termed as positive pressure or high-pressure areas. It utilizes a specialized ventilation system with HEPA filters which removes more air from the room than it allows to get inside thereby creating a negative pressure.

The goal is to prevent all airborne diseases such as Coronavirus (COVID-19), Severe Acute Respiratory Syndrome (SARS-CoV), Middle East Respiratory Syndrome (MERS-CoV), tuberculosis, influenza, etc. from contaminating surrounding areas. When designing the negative pressure room, care must be given to prevent leakage of air to its surrounding areas. The areas should be completely airtight and free from cracks, window leaks, false ceilings leaks, etc. which otherwise would defeat the purpose.

Now, let’s move ahead to our main topic.

How to convert an existing room into a negative pressure room?

Whenever a customer reaches out to us looking for a quick solution to convert their existing room into a negative pressure room, we provide the service in the following four steps:

Step 1 – Evaluation

We always start with the evaluation so that we know what are the site conditions, constraints, existing HVAC system, filters being used, and air leak sources among other key factors for a flawless design. For remote global locations, we have a questionnaire that can be filled by a customer before deploying the site team for inspection. We recommend the use of protective gear when visiting the location as many of these areas are high-risk environments.

Step 2 – Design

This is the most key step where all existing infrastructure issues, materials required, civil work requirements are considered carefully and a system is designed so that negative pressure is achieved in the rooms. The requirement for a negative pressure room is greater than or equal to 12 ACH (Air Changes per Hour) for areas under renovation or new construction and at least 6 ACH for existing facilities.

This can be done in the following three ways:

  1. To design a completely independent system that has its separate ducting and HVAC design.
  2. To modify or partially use existing ducts or HVAC systems.
  3. To install a portable negative pressure machine with its independent ducted design.

One important factor is to remember that the duct sucking the air out of the isolation room must not come in contact with existing air conditioning ducts which can cause massive cross-contamination.

Another important thing to do is to use a HEPA filter (High-Efficiency Particulate Air filter) in the ducts with filtration capacity of up to 0.3 microns. Since most of the airborne diseases are between 0.5 – 3 microns, it helps by preventing the exhaust air to spread contamination. For COVID-19, the use of HEPA filter has been considered as the best available solution present today but studies confirming the same are yet to come.

Step 3 – Execution

Now, since you have designed the system which is the hardest part, executing it is going to be a breeze. In this step, execution as per the design is very critical. We suggest to employ only qualified HVAC specialists who do not overlook the smallest details and if you decide to take our services – you are in safe hands.

One important thing which is easily overlooked is the safety of your service team as some of those hospitals, clinics or medical centers may already have infected patients. Make sure your team uses an N95 mask, wears protective gear, informs your client beforehand to clear the area and sanitizes themselves as much as possible.

Step 4 – Monitoring

The monitoring of pressure in an isolation room can be done with the help of pressure sensors which actively measure differential pressure between a positive pressure area(outside isolation room) and a negative pressure area(inside isolation room). These sensors or transmitters, in turn, send their data to a display mounted outside the room with color-coded indications such as green for correct pressure, yellow for warning, and red for an alert.

A pressure monitoring system can be integrated with existing BMS or SCADA system to give alerts at the BMS control panel. We can also configure Email and SMS alerts if required by our customers. We have our line of pressure sensors and monitoring systems made for Vacker LLC by Psidac in Sweden as per the highest European manufacturing standards.

As per ASHRAE Standard 170, Ventilation of Health Care Facilities every isolation should have a differential pressure monitoring system installed to constantly monitor pressure and give alerts for a rapid corrective response.

Precautions suggested inside a negative pressure room:

It is very important to take precautions as the safety of you, your service team, and your customers should not be jeopardized while making and maintain the negative pressure room.

  1. Always take protective measures and use protective gear to protect yourselves while making or maintaining an isolation room.
  2. Please DO NOT TOUCH the air-filters with bare hands, always use disposable gloves. Also, use sealed bags and dispose of the filters as per local and international regulations.
  3. Always replace the air filters and DO NOT indulge in activities such as washing or cleaning.
  4. Please use the air filters as provided by OEM manufacturer and DO NOT cut or modify them, it may degrade the efficiency causing the system to fail.
  5. For High – Medium Risk Environments such as Biohazard areas, Quarantine areas, and active isolation rooms – use of masks, suit, and gloves is mandatory and should have a bag-in bag-out system for containment and disposal. The HEPA filter used should be of minimum H14 class.
  6. For low-risk environments such as small offices, businesses, or any personal space – use protective gear but the need for suits may not be necessary. The HEPA filter used should be of minimum H13 class.

Also please see our negative pressure monitoring system for CSSD rooms, isolation wards, operation theaters etc.

For any further details please contact us.