Article Archive
November/December 2020

COVID-19: The Battle Against the Airborne Transmission of COVID-19 — Ultraviolet Solutions in Senior Care Facilities
By Eric Hansel
Today’s Geriatric Medicine
Vol. 13 No. 6 P. 28

As more is being learned about COVID-19, experts are paying closer attention to its transmission in microparticles through the air. For those caring for older adults and updating safety plans and protocols in enclosed facilities, there may not be a more important discussion under way.

Most people are under the misconception that a sneeze, for example, will only remain airborne for a short period and then land on a surface. That’s not true. Microparticles can remain airborne for an extremely long period of time, and that suggestions that merely wiping down surfaces in rooms and common areas is not enough to properly mitigate the spread of COVID-19 and other illnesses.

Airborne transmission of infectious agents occurs when bacteria or other viruses on respiratory droplets are expelled by sneezing, coughing, speaking, laughing, or exhaling, or are otherwise distributed into the air. Although the liquid or vapor around the infectious agent evaporates, the residue (or droplet nuclei) remains suspended in the air for very long periods depending on such factors as particle size, velocity, force of expulsion, particle density, humidity, rate of air flow, and the microorganism’s ability to cause infection.

This evolving understanding is resulting in an airborne battle against COVID-19 that has implications for nursing home owners and senior care facility managers throughout the country. Given how hard nursing homes have been hit—accounting for about 40% of COVID-19 deaths despite making up 1.2% of the population, according to a New York Times analysis—the role of air purification must be a key part of any comprehensive strategy to protect the health and well-being of employees, residents, and visitors in senior care facilities.

Front and center at the effort to combat COVID-19 in the air is ultraviolet germicidal irradiation (UVGI), often referred to as ultraviolet light, the most powerful of which is UV-C. As more senior care facilities look to provide peace of mind to their residents and their loved ones as well as employees, UV lighting solutions will become more common.

In use for more than 100 years, ultraviolet germicidal lighting is not new; however, many new products touting its effectiveness are now flooding the market. As owners, operators, and facility managers look to educate themselves, it can be daunting and difficult to cut through the choices to determine which products are proven and which are not, leading to ineffective results and wasted purchases.

While there’s a lot of information online, it’s not a decision to make without the guidance of an expert who will follow safety standards and properly cut through the marketing language to identify the correct solutions for your facility and those you care for and employ.

There is a lot to understand, but following are some of the basics.

Ultraviolet as a Pathogen Killer
Ultraviolet comes in three forms based on wavelength: UV-A, UV-B, and UV-C. While it’s produced naturally by the sun, UV-C and most UV-B are absorbed by the Earth’s atmosphere. This means people only typically come into contact with UV-A rays, which cause sunburn and increase the odds of skin cancer without proper precautions such as sunscreen. UV-B and UV-C can also cause health issues, particularly to the skin and eyes, but people are typically exposed through artificial sources such as a germicidal UV-C lamp.

Ultraviolet is commonly used to disinfect air, water, and food and has been implemented widely in hospital operating and isolation rooms and by the water treatment industry. Ultraviolet is effective against viruses and bacteria because it damages the microbe cells’ DNA and prevents them from replicating, which essentially makes them inactive. It’s been effectively used against MERS, SARS, and Ebola in the past and provides an important layer of defense, particularly against pathogens that may have mutated or are resistant to antibiotics.

Employing a customized ultraviolet solution should not, however, only be thought of in terms of COVID-19. It also drastically reduces the threat of airborne transmission from other viruses, such as the flu. A study during an influenza epidemic found that rates of influenza infection in a VA hospital building with upper-room air treated by UVGI were almost 90% lower than those in nearby hospital buildings without UVGI.

UVGI also helps eliminate harmful bacteria, mold, and fungus that builds up in the air handling systems and is often recirculated through the air. It’s particularly effective at purifying the air in shared indoor spaces where people congregate for meals, activities, entertainment, and general visitation.

Best Practices for Disinfecting Air in Enclosed Spaces
Heating, ventilation, and air-conditioning (HVAC) systems are critical to promoting indoor environmental air quality and must be well designed, installed, and maintained for effectiveness. Transmission of airborne contagious diseases can be mitigated or exacerbated by a facility’s HVAC system.

In the 1990s, there was a push to use UV-C to improve indoor air quality by reducing the microbial buildup within HVAC coils—a movement that’s rapidly expanding now.

There are three best practices for disinfecting the air in an enclosed space that are critical for trying to create a safe and healthy facility. Any successful air disinfection strategy employing ultraviolet will have one to three components—air handling units, air ducts, or upper-room installation—depending on the facility.

Air handling units, such as air conditioners, can harbor a lot of things you do not want to breathe. So treating sources of contamination in the HVAC and in the air while it is moving through an air handling system is critical and typically much more effective than mobile air cleaning units.

Cooling coils and drain pans inside the units are often wet, leading to mold and bacteria growth. Over time, these substances build up and eventually shed particles into the air that subsequently enter the occupied spaces, posing risks, such as noninfectious respiratory health effects. Irradiating the cooling coils and drain pans with ultraviolet can dramatically reduce mold and bacteria growth or destroy the microbial films that previously accumulated on the surfaces, keeping the air coming out of the air handling unit clean.

UVGI systems installed in air ducts treat moving air streams in HVAC systems to inactivate and eliminate airborne microorganisms. System performance and costs to implement and operate the system depend greatly on the output of the UV lamps and the exposure time, which are affected by the temperature and the velocity of the air passing through the UVGI device.

For upper room spaces, which are rooms with high ceilings, UVGI can be installed typically above head level at seven feet or higher and helps purify air, particularly in more crowded areas such as a large conference room or cafeteria, where it’s tougher for air handling units to circulate air. These lamps face the ceiling, purifying the air above and around it and complement UV lamps installed in air ducts or air handling units. Upper-room UVGI, with a wavelength range of 100 to 280 nm (UV-C), efficiently disinfects airborne microbial organisms by inhibiting their ability to replicate.

Case Study: Surgical Grade Lighting and NexCare Health Systems
One senior care provider in Michigan is installing surgical-grade ultraviolet solutions that have commonly been used in hospital operating rooms to its nonhospital care setting.

NexCare Health Systems is a provider of postacute rehabilitation and long term care in Michigan. Operating 26 locations, consisting of nearly 3,000 beds, its services include physical, occupational, and speech therapies along with long term care. Its sister company, the Wellbridge Group, provides inpatient short-term skilled nursing and rehabilitation services such as physical therapy, occupational therapy, and speech therapy after surgery or illness.

At the height of the COVID-19 pandemic's spread, on a single day in April 2020, 300 residents were positive for the virus in the company's 26 facilities, which amounted to 10% of its 3,000 beds. This led to the creation of its “Go Forward” plan to act quickly to develop and enact additional safety procedures and solutions.

Partnering with our lighting group, NexCare implemented a customized ultraviolet system as part of its comprehensive operational safety plan. Our team conducted an in-depth study of each of NexCare and The Wellbridge Group’s facilities, visiting each location and inspecting the air handling systems onsite.

After completing its analysis, the team installed commercial grade ultraviolet within each of the air handling units across the 26 locations. With this customized ultraviolet solution, the air is cleaned “like a carwash” continuously, 24/7, significantly reducing the spread of airborne transmissions of viruses and bacteria.

While such a solution represents an investment, NexCare integrated this into its overall effort to keep residents, staff, and visitors safe. At one NexCare facility, the cost of its UV lighting solution calculates to less than $13 annually per resident and staff.

Not All UV Products Are Created Equal
In some ways, it’s the wild west in the marketplace as manufacturers push their UV lighting products in response to COVID-19. This push to market is reminiscent of when LED lights became popular a decade or so ago, when LED became common in most facility management plans.

With ultraviolet, just as with LED, it’s essential to remember that not every product is created equally and there are no one-size-fits-all solutions. Knowing the difference is critical to finding a solution that best serves your facility.

A customized ultraviolet solution serves as a strong foundation of any facility’s comprehensive safety. Ultraviolet is the starting point, especially with the threat of airborne transmissions.

There are safety implications involved with exposure to ultraviolet that need to be taken into consideration depending on where the lighting is installed and whether people can access that area. Installation and operation can be safe, but proper precautions and protocols need to be followed.

UV Lighting Is Only Part of the Solution
As with any strategy to defeat a virus or pathogen for which there is no vaccine, there is no silver bullet. While a customized ultraviolet solution is an essential part of a COVID-19–related safety strategy, it is important to remember it is only part of the solution. Mitigation factors and practices such as hand washing, disinfecting surfaces, social distancing, and personal protective equipment are all important elements that should continue.

That being said, any effort to seriously combat COVID-19 and future viruses in enclosed spaces will be compromised without consideration of how to disinfect and purify the air. Moving forward, implementation of ultraviolet solutions will continue to be standard in all facility management discussions and become increasingly common in nonhospital settings such as long-term senior care and rehabilitation facilities.

— Eric Hansel is president of Expert Lighting Group, a certified lighting efficiency professional, and a member of both the International Ultraviolet Association and Illuminating Engineering Society.