Table of Contents
Prefabricated cleanroom components allow faster construction of sealed and HEPA filtered triage areas for emergency rooms and hospitals. New generation fan filtration units with reverse blowers and HEPA filters exhaust clean air externally and curb airborne contamination or viruses such as COVID-19.
Negative vs Positive Pressure Hospital Rooms
For a negative pressure room, the sum of the mechanically exhausted air must exceed the sum of the mechanically supplied air. The result is a negative pressure differential. How does one decide on the best approach to containment areas in healthcare systems when both positive and negative air pressure areas are needed?
Single Pass Design
Recirculating Design
Negative Pressure
Softwall Containment
Negative Pressure Hospital Rooms
Rooms for containment of infectious diseases, viruses and pathogens have neutral or negative pressure depending on the risk classification. Negative pressure hospital rooms prevent air contamination from leaving the envelope of the enclosure by evacuating air faster than introduced.
A negative or positive pressure area may consist of multiple sealed and partitioned structures. An outer structure, called an anteroom, allows for a cascading increase or decrease in pressure between the interior and exterior walls.
Hardwall Triage Structures and Ceilings
Each containment structure includes integrated hardware for a T-grid ceiling system. The T-grid ceiling system is capable of self-supporting the ceiling mount fan filter systems. The number of fan filters is customized based on the size of the area and ceiling height.
Air Change Requirements for Hospital Containment Zones
Generally, negative pressure rooms for infectious disease and aerosol containment require at least 12 air changes per hour. The CFU of each fan filter is either variable or switch toggled. The number of fan filters, CFUs per blower, input/output airflow, and room size will dictate the total room air exchange rate. There are reasons to increase the number of fan filters instead of ramping up CFU including max efficiency curves, system redundancy, filter lifetime, and noise floor.
CDC Infectious Disease Control Negative Pressure Air Change Requirements (2003)
- Pressure differential of 2.5 Pa (0.01-in. water gauge) measured at the door between patient room and anteroom
- Air volume differential >125 CFM, depending on anteroom airflow direction (i.e., pressurized versus depressurized)
- Anteroom airflow patterns (i.e., anteroom is pressurized in the top and middle panels, and depressurized in bottom panel).
“This isolation area receives numerous air changes per hour (ACH) (≥12 ACH for new construction as of 2001; ≥6 ACH for construction before 2001), and is under negative pressure, such that the direction of the airflow is from the outside adjacent space (e.g., corridor) into the room.”
Guidelines for Environmental Infection Control in Health-Care Facilities (2003)
Softwall Curtain Containment with Negative Airflow Exhaust
Not all scenarios need floor to ceiling containment structures. Hybrid approaches include softwall curtain enclosures, air evacuation, and clean corridor designs which can either create air buffer zones and containment structures.
Hybrid approaches such as curtain enclosures do not provide a qualified negative pressure containment, however, when calibrated to the proper ACH (air changes per hour) will provide a neutral air barrier and log reductions in airborne virus levels.
Overall, these are highly effective safety barriers built for your location to mitigate the transmission of dangerous airborne contagions. This cost-effective vinyl separation curtain is suspended from the ceiling and is quickly customized to perfectly fit your space and keep your employees’ health uncompromised.
Hospital Negative Pressure Room Requirements
The air gap between two separate rooms on a shared wall is measured by water channel ( WC or inches of water). For most negative pressure rooms the WC is typically 0.01 – 0.03-inch water gauge (in. w.g.)
or +-2.5 Pascals (Pa) between each partition of lower or higher pressure (including the outside air)
Air balancing within a containment curtain is less complex than a sealed, hardwall room, but also less effective. A single fan filter unit within an immediate containment is usually capable of log reductions in airborne virus levels. The advantage of containment curtains for hospitals is that patient areas already have integrated slide curtain hardware.
Read: Modifying Positive Pressure Rooms for Negative Pressure
Negative Pressure Room Scenarios:
- Airborne contagions
- Opportunistic pathogens and viruses
- Hazardous or toxic waste saturation/fumes
- Infectious quarantine or isolation
Positive pressure triage rooms are effective when bacterial cleanliness and infection control is the primary concern. For example, a temporary mass trauma center, field hospital, burn unit, or temporary intensive care unit for compromised hosts.
Positive Pressure Containment Room Scenarios:
- Sterile procedures
- Immunocompromised patient rooms (e.g., hematopoietic stem cell transplant or
- Solid organ transplant procedure rooms) and orthopedic operating rooms.
Mobile Negative Pressure Filtration Systems
We provide transportable air filtration solutions for healthcare isolation rooms and negative pressure air handling.
An integrated fan blower, HEPA filter, and motor are affixed to a mobile cart in which a single ceiling-mounted filter can evacuate enough to provide negative pressure for rooms of up to 400 sq. ft.
The cradle is assembled and outfitted with 2″ castors and breaks for easy movement.
The FFU’s (fan filter units) are actively powered and fitted with a power cord, integrated hood, and 10″ – 12″ duct-collar adapter. The collar adapter connects the fan filter to most standard HVAC return exhaust systems if possible, to an outside area, or to a parallel space if deemed appropriate.
CleanPro® Cleanroom Fan Filter Units
CleanPro® self-contained 99.99% efficient HEPA or 99.9995% efficient ULPA-equipped fan filter units are available for a variety of critical applications.
Temporary Surge Areas
The appropriate configuration for your facility must consider state and local authority such as fire, health, and building codes. According to the State of MN (2016) The three options for creating a temporary surge area using HEPA filters are similar to Types #1 and #2 of TNPI for a patient room.
- Each of these options should be used in conjunction with a safe area (anteroom).
- Discharging through a window Discharging to an adjacent space Discharging to a return air system
- These three options may be used in combination to achieve the desired pressure differential.
Get Help with an Emergency Room Triage Design or Engineering Layout
PAC (that’s us) is a provider of variable filtration and containment solutions.
Design
PAC works directly with customers and manufacturers for end-to-end engineering of containment structures, filtration systems, and necessary installation hardware. We handle all of the upfront engineering for manufacturing including the final form, fit, and function of the on-site system.
Installation
For smaller containment systems, especially those in hazardous or high-risk areas, most facilities will handle the installation internally via the facilities team or familiar contractor. These systems are extremely simple to erect and wire with basic tools and hardware, thus virtually zero modification is required for on-site installation.
Our existing cleanroom walls could be repurposed to build isolated patient partitions in medical triage tents, intake, screening, or temporary care areas.
- Customized Dimensions & Features
- Dimensions are customized to your space.
- Easily integrate windows and openings appropriate for your business.
- Hygienic & Functional Design
- Prevent physical contact while maintaining normal interactions such as barcode scanning.
- Tri-panel design mitigates airborne transmission from coughing or sneezing.
- Easy to Clean
- Hygienic aluminum and acrylic material can be cleaned using wipes, bleach or disinfectant.
Negative Pressure Rooms for Hospitals
Production Automation Corporation (PAC) is a factory-direct cleanroom supplier for environments, supplies, apparel, and furniture.
Every PAC product is backed by dedicated customer service, sales support, and in-house specialists.
Need help with a technical manufacturing solution? We’re the specialists in your back pocket.
