For congregate spaces where multiple people with unknown infectivity will frequent, keep these four things in mind:

Provide a safe pathway to the

space when planning.

Use an air cleaner, portable air cleaners

Social distance in shared spaces while

wearing appropriate PPE to limit spread.

Filter or minimize movement of air

between zones.

Reduce aerosol contamination in the corridor by rebalancing supply and return or exhausting from room, creating directional airflow in the room and placing potentially infected persons away from the door PPE is worn by all except to accommodate exam needs Create directional airflow and reduce infectious aerosols and droplets in the room by recirculating air through a HEPA air cleaner sized for rapid cleaning with off and low speed for exam acoustic need and high speed for air cleaning between use. Or, recirculate air through a portable HEPA air cleaned sized for rapid cleaning between use. Both only use energy when on. Provide ante room for doffing and aerosol control either at the room or unit level.

The exam room is used many times throughout the day, which requires more attention between uses to reduce spread.

Reduce the potential of

aerosolized pathogens moving

into the corridor or into other

spaces through recirculation

without HEPA fltration.

Reduce the potential of

tracking pathogens into the

corridor.

Reduce the quantity of

aerosol pathogens in room air

and clean the room air

between room uses.

Bring these three elements to the forefront when designing for shared and frequented spaces with a high risk of infected patients:

For efficiency in staffing, cohort patients into a single

wing to create a containment unit where staff can don

and doff PPE when entering or exiting the wing.

Staff efficiency in a pandemic is critical. To save time, design an isolation area with multiple rooms without requiring full change of PPE when traveling between rooms. Create space and protocols to minimize spread of pathogens.

Here, staff are given appropriate space for donning and removal of PPE, while HEPA filtration continuously cleans the air within the patient care space. With the addition of the ante room barrier, pathogens are much less likely to escape.

It’s better to isolate with ante rooms between the patient room and the corridor to create a buffer of biosafety for donning and doffing PPE.

“Making a room negative pressure gives you a false sense of security because when you open that door you lose all your pressurization“

Containment is limited with negative pressure rooms attached to a corridor.

Pathogens within the room are secondary. The primary concern is in transferring pathogens to other spaces.

For patient rooms where staff are using PPE and no visitors are present, keep these two considerations in mind:

Reduce the potential of aerosolized pathogens moving into the corridor or into other spaces through recirculation with HEPA filtration

Reduce the potential of tracking pathogens into the corridor with staff and patients while providing appropriate space for donning and removal of PPE

Biocontainment Means Separation and Filtration

When approaching biocontainment and biosafety within a healthcare facility,

several issues impact the ability of an infectious pathogen to spread.

NEGATIVE PRESSURE

AIR CHANGES

HEPA FILTERS

AIR QUALITY

How have air quality concerns impacted healthcare facility strategy?

Biosafety and biocontainment have been brought to the forefront since the arrival of COVID-19. Patients and staff alike are concerned with the safety of their built environments. Access to and proper use of personal protective equipment (PPE) are the primary concerns, and work in tandem with strategies to ensure that mechanical systems meet biosafety and biocontainment best practices not just for the foreseeable future — but for the long-term as well. That means these systems must represent economically viable solutions.

The important question is: Is the dilution air clean? Outside air with high ventilation rates costs a lot of money. There are equally effective alternatives. But don’t move contaminated air to other spaces without HEPA filtration.

This often-used term is also misunderstood. Pressure between the corridor and the room works with the door closed, but with the door open, the pressure is equalized so when someone walks in or out, contaminated air may move from the room to the corridor. The addition of ante rooms may solve the doorway issue by creating a buffer. Most experts agree that you can’t have a single door without a substantial interchange of air.

Low air change rates (four to six) within a space are effective in minimizing the spread of pathogens. High air change rates (more than 30) are effective at cleaning the air. Different rooms have different conditions; for example, a continuous source of pathogens from a patient in a room is different than a burst source from an infected person walking through a space.

HEPA filters work well for viruses as they are at least 99.97% effective with particles of .03 microns.

OUTSIDE AIR

— Healthcare Executive, Central U.S.

are equally effective, with HEPA flter to

remove pathogens between uses.