Now more than ever, building owners and occupants have their minds on indoor air quality and the solutions they can utilize to prevent the spread of viruses like COVID-19. As a HVAC contractor, there are a quick solutions to improve indoor air quality in a residential space that can serve as a guide during a routine service call. However, the more complex the problem the more important it is to understand how indoor air quality concepts function in a conditioned space.

Are HVAC contractors prepared to offer indoor air quality solutions to fight the coronavirus? The short answer, according to 35-year indoor air quality expert John Ellis, is "no." 

Ellis teaches Indoor Air Quality workshops through Daikin/Amana/Goodman that are designed to help contractors understand the complexity of indoor air quality. The course is approved for 16 CEU NATE credits and helps HVAC contractors use a blend of building science and forensics to ask the right questions and offer the right indoor air quality solutions.

Here, Ellis answers a few questions of our own about the HVAC industry’s preparedness to provide solutions to the coronavirus pandemic.

As a more than 30-year veteran in the HVAC industry, how would you rate the HVAC industry’s level of preparedness to taken on the coronavirus in buildings?

The HVAC industry is ill prepared. Everyone is looking for a quick fix, plug and play, cookie cutter solution, but no one wants to do the real work. Indoor air quality is not a “one size fits all” process but rather a multi-discipline approach. Every client, every home, every building is unique. The HVAC community struggles to understand the complexity of indoor air quality.

There needs to be a paradigm shift in the way we think and approach indoor air quality. There needs to be much, much more training, bringing in building science, building forensics, and mechanical science. If HVAC companies genuinely want to offer their clients the best indoor air quality solutions during a pandemic or not, they need to have a process in place to address each situation on a case-by-case basis.

In the HVAC community, there always seems to be a debate about whether indoor air quality solutions are warranted or necessary. What is the cause of the confusion?

The main reason for the debate is lack of real knowledge. A lot of companies use it as a catchphrase. They offer it but don’t understand it. I think the HVAC community has some of the smartest people and the best group of professionals to go after the indoor air quality market. We control humidity, filtration, air exchanges per hour, and much more. HVAC has the biggest impact on a building or home.

Do you think there is any room to debate the need for indoor air quality solutions after what we’ve seen in this coronavirus pandemic?

Yes. I based my whole business model around indoor air quality. Even as a contractor in California, IAQ was ingrained in our everyday business. Pandemics will come and go. Having a strong working knowledge in IAQ will better prepare contractors to serve their clients’ needs. I think now, more than ever, people will have become more aware of the importance of indoor air quality and having a clean, healthy, home environment.

It has been said that we spend 90 percent of our time indoors. With the current events, and the stay-at-home orders, that number is much higher. Our homes are supposed to be our sanctuary, our safe haven. HVAC contractors offering solid IAQ solutions can help homeowners achieve that goal.

Which IAQ service can you envision being the most popular and or warranted as coronavirus continues to be a threat?

IAQ is not just a single service but a process. A contractor needs the ability to go into a project and investigate, analyze and quote. The investigation process consists of gathering evidence and data. Once that is complete, the data is analyzed. From there, a quote is presented based on the information gathered. Prescription without diagnosis is malpractice.

As an HVAC contractor, the three main aspects of indoor air quality are: filtration, ventilation and humidity control. However, the contractor must also consider how the building is performing, how the mechanical systems are performing and how the occupants are interacting with the two. We, as an industry, need to look at the whole house or building as a system. Then and only then, can we start to understand the dynamics of IAQ and all it entails.

Be straight with me. How should contractors go about separating successful services from the snake oil?

Offer real solutions. Stop the widget upselling. Contractors tend to have the misconception that certain products are like bug-zappers: zapping pollutants, bacteria, microbials, and viruses in mid-air. Ultraviolet light, photo catalytic oxidation, those are the snake oil.

Take PCOs for example. PCO Systems reduce concentrations of pollutants through a process called photo catalytic oxidation. The system’s filter captures particles and bio aerosols removing them from the air stream. As the odor- and chemical vapor-filled air stream flows over the ultraviolet light, the air stream is exposed to the catalytic surface (titanium dioxide-coated metal filter). The light energy and water vapor in the air activate the titanium dioxide catalyst, which generates hydroxyl radicals. These particles break down the odors and chemical vapors into carbon dioxide and water.

Essentially: PCOs are designed to break down some pollutants in the air. However, PCOs tend to be small devices placed in large plenums, where air has room to escape past the device. While the PCO does impact some air flowing through, it takes many passes to impact the air quality. Another aspect of this technology is that it raises carbon dioxide levels and creates formaldehyde. Basically, contractors need to understand the technology of different products available and what their limitations are. Matching the right product for the right application is paramount.

We’ve all heard the horror stories about coronavirus infections spreading like wildfire through apartment blocks and homes. From a scientific indoor air quality perspective, what could be going on in the air stream of these spaces that would cause this to happen? Is this the same concept as germs spreading through a plane’s “recycled air”?

Let me start by saying this: a building, apartment, or a home can become contaminated. But the virus needs a host, and that’s where we as humans come in. The virus is spread by droplets of sputum. Coughing, sneezing, or bodily fluids are typically the vehicles. We’ve all heard it said that the virus can live on surfaces for several days. Apartments have a lot of common areas and shared spaces such as stairwells, landings, halls, and laundry rooms. If the virus is airborne, and an apartment building has shared mechanical, it has the potential to spread from unit to unit. Another determining factor would be building pressures and interstitial communication.

Our previous home is a perfect example. The neighbors’ cooking and smoking odors would travel through the building’s cavities and into our condo unit because of the pressure differences. In a home, when the virus is airborne, it has the potential to spread from room to room. Everyone in close proximity breathing the same recycled air is in a perfect environment for the virus to spread. I have often heard airplanes being referred to as a flying Petri dish.

In homes where occupants are sensitive to many allergens, copper duct has emerged as an indoor air quality solution in the HVAC industry. Why not make more HVAC systems from copper duct to cut down on microbial growth?

First of all, it is cost prohibitive. By the time it comes from the manufacturer to the distributor, and then to the contractor, it becomes quite expensive. Second, it is hard to work with. I’ve had the experience to work with copper ducting and materials. The metal is very soft, and it bends and kinks very easily.

Copper ductwork

Third, copper ducting is a great conductor of temperature. It condensates, or sweats, very easily if it is not insulated properly. Fourth, the anti-microbial properties have very little effect since germs, viruses, and bacteria travel at velocity through the ducts, not coming into contact with the copper.

Another hot-button topic right now is how the coronavirus pandemic will change duct fabrication. Let’s say a government body starts to mandate duct cleaning or some other solution that makes homeowners feel better about germs.

If they mandated duct cleaning, most duct cleaning techniques do not address microbials, viruses, or bacteria, to a point of sterilization. In some instances, if not done properly, duct cleaning can make IAQ worse. Let’s talk about UV technology. UV lights purify by attacking the contaminants and microbes at their basic molecular level, and then damaging them enough so that they may no longer reproduce.

However, this purification process is directly related to three very important factors: intensity, exposure time, and distance. How well the process works depends on the intensity of the UV light spectrum; the amount of time the organism is exposed and the distance the light is to the organism. This technology works very well on wet surfaces, such as a coil or pan. Yet even though there have been advances in UVC technology, they don’t work well in an air stream. So, yes, mandating duct cleaning, or ducts with UV technology, without clear performance results would be overkill.

ultraviolet light

The HVAC industry had a hard time handling energy mandates and directives, like third-party verifications (HERS). Mandates and directives are often prescriptive. So for instance, in 2005, the California Energy Commission introduced their prescriptive mandates for the HVAC industry. There have been several revisions since then. Their prescriptive measures included: tight ducts, fan watt draw, and refrigerant charge. Each system had to meet a certain standard. After millions of dollars in incentive programs, and thousands of houses completed, energy savings were very minimal. So can you imagine trying to put a prescriptive mandate on indoor air quality? It would be next to impossible.

As to whether the HVAC industry could handle the issue of indoor air quality by themselves, without mandates, depends largely on the working knowledge and education of the contractors. Indoor air quality is often a team approach. It is also a multidisciplinary. A contractor may need to team up with a certified industrial hygienist, a mold-remediation company, an asbestos abatement company, an air sealing and insulation company, or a building science professional.