Indoor Air Quality: Everything You Need to Know and More

By | May 2021

Enduring a global pandemic drove home a few things that apply to indoor air quality:

  1. Focus on what you can control.
  2. Indoor air quality determines how healthy our spaces are.

The upside? We can control indoor air quality to make our facilities, buildings, and spaces safer.

You’re busy, so here’s what you need to know about indoor air quality, all in one place. We drew from industry, science, and public health to create your ultimate indoor air quality guide. This guide will help you prepare your facility post-pandemic—and increase health, safety, and productivity for years to come.

Jump to any section if you already know what you’re looking for.

This article gives an overview of indoor air quality and how it affects your triple bottom line  (3BL).

Is My Building Healthy?

Indoor air quality determines your building’s health.

With all the uncertainties in the world, it feels good to make tangible changes. Improving indoor air quality not only improves your occupants’ well-being, but also has very real payoffs for you in productivity and profits. Before we get to some ways you can improve your indoor air quality, we’ll talk a bit about why it matters and what you’re up against.

Harvard’s Healthy Buildings lab collected data for over 40 years about what makes a building “healthy.” They distilled these findings into 9 points:

9 foundation of a healthy building
  • Air quality*, Dust & Pests*, Moisture*, Thermal health*, Ventilation*, Lighting & Views, Noise, Safety & Security, and Water Quality.

*Directly managed by your heating, ventilation, and air conditioning (HVAC) system.

Yep, that’s right, the minds at Harvard have been studying how to make healthier buildings for over 40 years. Over half of what they’re checking are things you can directly manage through your HVAC system.

Indoor air quality dominates conversations about healthy buildings consistently—but aside from the obvious, what does it really mean?

Indoor Air Quality (IAQ) specifically describes how pollutants, temperature, humidity, and similar factors affect health, comfort, and performance.

The American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) teamed up with architects, building owners and managers, technicians, and eco groups to create a comprehensive guide to indoor air quality (IAQ). It’s over 700 pages, so if you’re planning to check it out, we recommend starting with the primer.

ASHRAE traces poor indoor air quality back to 9 root causes:

  • Building design and construction
  • Building wasn’t commissioned—checked to see it works for its occupants
  • Dirty and damp ventilation systems
  • Indoor contaminant sources
  • Indoor equipment and activities that add to contaminants
  • Moisture in the building enclosure
  • Poor filtration and air cleaning
  • Poor outdoor air quality
  • Poor ventilation rates
Indoor Air Quality FREE online assessment tool

The Benefits of Good Indoor Air Quality

Indoor air quality is the single largest defining feature in our built environments.

Have you been behind a broken-down car at a red light and choked on the fumes? Pollutants in our indoor air are often more dangerous and less obvious.

The upside? We also have more control over our indoor spaces. Here’s a sneak peek at some costs and benefits we’ll discuss here.

Sure, better air quality is good for our health—but just how important is it?

50 percent of illnesses caused by indoor air pollution

Did you know indoor air pollution causes up to 50% of respiratory illnesses?

Yes, 50%.

Fair warning: we’ll keep coming back to that number, ‘cause it’s a doozy.

Depending on where you’re reading this from, this isn’t just a Canadian problem—it just happens to be where we’re writing to you from. Indoor air quality is a universal concern. For example, Facilities Management Middle East reports indoor spaces “can be up to 5 times more polluted than the air outside from the build-up of formaldehyde from a wide range of items. This includes new textiles such as carpets, which release toxins into the air.”

And it turns out just “cracking a window” won’t always cut it. For example, Fisk and Chan found 65% of the outdoor air particles we inhale actually happens while we’re indoors. So, on top of all the extra junk indoors (like mold and off-gassing), you may also be breathing in pollution from outdoors.

Having briefly summarized some costs and benefits, let’s dig a little deeper into them as they relate to improving indoor air quality.

Improve Occupant Health & Experience

Yep, unsurprisingly, health is the number one benefit of improved indoor air quality, hands down.

Indoor air quality is always important. It turns out though that it often takes issues like asthma, allergies, smoke, and viruses (such as the coronavirus/COVID-19) for us to prioritize indoor air quality. Viruses aside, there are still many types of indoor pollutants—and even if we’re only focusing on particulate pollution, improved filtration reduces mortality rates. Wow. Why does indoor air quality play such a vital role?

Well, North Americans spend 90% of our time indoors. This is increasingly true anywhere with extreme weather. Plus,

  • 1 in 10 Canadians have asthma (3.5 million)
  • 1 in 6 Canadians suffer from allergic rhinitis (6.3 million)

[ss_click_to_tweet tweet=”On average, there’s 2-5 times more pollution indoors than outdoors, and over 10 million Canadians are sensitive to poor indoor air quality.” content=”On average, there’s 2-5 times more pollution indoors than outdoors, and over 10 million Canadians are sensitive to poor indoor air quality.” style=”2″ link=”1″ via=”1″]

indoor air quality stats

Data suggests climate change may also worsen conditions for the 10 million Canadians sensitive to indoor air quality.

A recent report on how climate change impacts air quality and human health anticipates that we’ll experience: worsened health impacts from ground-level ozone and wildfires, as well as worsening allergy and asthma conditions. This means the 10 million Canadians sensitive to indoor air quality will experience worse symptoms—and have more sufferers joining their ranks.

People can just stay inside if it’s smoky or allergy-season, right?

As it turns out, it’s not so simple. According to the US Environmental Protection Agency, “climate change may worsen existing indoor environmental problems and indoor air quality, and it may also introduce new problems as the frequency or severity of adverse outdoor conditions change.” For example, they point to glaring examples like forest fires (smoke) and droughts (dust), but also flooding (mold, mildew, and increased pesticide usage as competing species flee indoors).

In short, indoor air quality will become even more important in the years to come.

There are also a mounting number of health concerns related to indoor air quality. These include Sick Building Syndrome and Building-Related Illness.


What the Heck are Sick Building Syndrome (SBS) and Building-Related Illness (BRI)?

Lately, we’re hearing more and more about Sick Building Syndrome (SBS) symptoms. Nope, it’s not the building that’s sick, per se… it’s more about how it can make people sick.

Sick Building Syndrome describes acute symptoms people experience in a specific space—and symptoms improve when they leave that space. Examples include fatigue, headaches, breathing problems, or irritated skin, eyes, nose, and throat. They tend to happen where there are lower ventilation rates, significant amounts of indoor pollution, and when temperatures aren’t ideal.

People with Building-Related Illnesses (BRI) may present similarly, and also get better when they leave the contaminated space. The main difference between the Sick Building Syndrome (SBS) and Building Related Illnesses (BRI) comes down to finding what’s causing it.

Sick Building Syndrome symptoms don’t point to a specific disease or pollutant. Building-Related Illnesses (such as Legionnaire’s disease) do point to a specific disease or pollutant.

Ventilation Rates Sick Building Syndrome Symptoms Indoor Air Quality Gateway Mechanical

These individual health issues not only affect your occupants, but also impact your facilities, buildings, and spaces.

The Cost of Poor Indoor Air Quality

If there was one thing you could do to improve employee performance, productivity, absenteeism, and turnover, would you do it? Yes, one thing that could improve all of it. Well, it turns out there is—indoor air quality directly impacts performance, productivity, absenteeism, and turnover.

To put it in perspective, did you choke a bit the last time you walked into a tire warehouse with a lot of volatile organic compounds (VOCs) in the air? Or the last time you passed a salon where someone’s getting a perm or a manicure? You may recall how hard it was to focus on anything else when your breathing’s compromised—even just from pollutants you could smell. You may have wanted to spend less time in those places. The same applies to your occupants.

We may be conserving our pennies, but there has never been a better time to put your occupants’ health first. People are understandably expecting more of their spaces these days.

Your occupants’ health matters. You can also be part of the solution in slowing the spread of the coronavirus/COVID-19. We’re all in a position to minimize risks and prioritize our occupants’ health. Aside from just being the right thing to do, showing this leadership also benefits you overall. Prioritizing people is another way to future-proof your business, by starting in the right direction before reaching a crisis.

In short, investing in people through indoor air quality benefits your business’ reputation and long-term returns.

What do the benefits to your business look like in the short term? Let’s talk about performance and productivity first.

Improve Performance and Productivity

Remember the iconic 90s Radiohead song Fitter, Happier? Kudos if you do—it’s a classic. Improved indoor air quality makes occupants happier and more productive, so the lyrics “Fitter, happier, more productive” keep running through our heads. (You’ll have to sort out the fitter part, yourself).

Indoor air quality affects how much time people spend at work or school—and it affects their performance while there. One study found increasing ventilation improves performance 0.3-0.8% per 10 cubic feet per meter (5 litres per second) per person increase in ventilation rate. Harvard Business Review reviewed several studies, finding that:

You can also measure how air quality affects productivity by looking at schools, which have key performance indicators (KPIs) built right in. Improved air quality means higher grades. One study found by improving ventilation, student grades improved by up to 15%.

Reduce Absenteeism and Turnover

For starters, from a net profit and bottom line perspective, retention strategies consistently pay off when we’re talking about any occupants, including employees, customers, and tenants.

Good indoor air quality attracts and keeps better occupants for your space, and better talent for your team. Case in point, Harvard Business Review suggests a “healthy building will go from a ‘nice to have’ to a competitive, ‘must have’” to attract and retain the talent your organization needs.

Poor indoor air quality cuts into your building management and people management resources. Why? Well, poor air quality impacts how much time occupants spend in your space. If people are less inclined to spend time in your space, this forces you to deal with more absenteeism and turnover.

It’s also worth noting that as we navigate the pandemic, your occupants’ expectations are understandably increasing when it comes to safe facilities and clean air.

Let’s talk about absenteeism first. It’s costly and affects productivity and performance. According to Statistics Canada and other sources:

[ss_click_to_tweet tweet=”Poor ventilation accounts for over 50% of sick leave and 250K Canadians miss work each week because of poor indoor air quality.” content=”Poor ventilation accounts for over 50% of sick leave and 250K Canadians miss work each week because of poor indoor air quality.” style=”2″ link=”1″ via=”1″]

250 thousand people miss work every week due to indoor air pollution

Don’t forget, absenteeism also has a domino effect. It compounds stressors on the rest of the team, since covering off for others increases workloads and burnout risks. When your colleague can’t make it in and their phone’s ringing non-stop while you cover their portfolio and set expectations—chances are it dampens your morale and well-being, too.

Ok, so poor air quality’s costly for my business.

What can I expect as a return on investment (ROI), if I invest in improving indoor air quality for my facility, building, or space?

Harvard Business Review describes healthy buildings as a “new minimum,” and “a first line of defence against disease.” They estimate the returns on investing (ROI) in ventilation improvements saves employers up to $6,500–$7,500 per person per year.

That number seems high, but remember salaries are the biggest cost for any business. According to the American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE), salaries “dwarf energy by a factor of 50 or even 100.” In purely economic terms, having employees well and working pays dividends—they’re any business’ biggest investment.

These costs make more sense when you remember that calling in substitutes and overtime-paid favors from other staff costs more. If your organization doesn’t have leave coverage in place, you need to also remember that risking burnout by overextending remaining staff members adds to overall costs.

So… where do you start?

Turns out that even just improving your filter efficiency gives great returns. One study found that in using filters with a Minimum Efficiency Reporting Value (MERV) of 13, the benefits outweighed the costs by 10 times. For example, cost per occupant (annually), could be $7.50 to $27, with benefits of up to $800 per occupant.

Indoor air quality improvements may even save you money on employer health plans. Investing in healthy employees pays off, so many employers have done the math and offer group plans for their staff. Remember how indoor air quality may be responsible for over 50% of sick leaves? With that in mind, some health insurance companies may manage their risks by factoring indoor air quality (IAQ) into their insurance billing structures.

I Just Renovated So It Should Be Ok, Right?

All renovations need to account for indoor air quality (IAQ) to ensure you get the best return on your investment (ROI).

Newly renovated spaces often have beautiful (but stinky) new finishes and furnishings. Most people know about these off-gassing volatile organic compounds (VOCs) and how they affect health and productivity—because they can smell them.

VOCs off-gassing from renos are hard to ignore. However, people may not realize that renovated spaces can have additional hidden problems. These less obvious problems come up when design and construction stages didn’t prioritize indoor air quality.

The Environmental Protection Agency (EPA) reminds us that weatherizing a building (to make it more airtight) improves energy efficiency—but makes indoor air quality (IAQ) more important than ever. When renovations and weatherizing don’t take air quality, ventilation, and humidity into account, it creates serious problems. For example, renos can release lead and asbestos into the air, plus pollutants like radon and mold can build up faster in airtight spaces.


Boost Your Bottom-Line

Businesses leading with a triple bottom line (3BL) consistently outperform those that don’t.

Investing in indoor air quality (IAQ) for your occupants’ health pays off for your brand overall. This especially applies when following a triple bottom line (3BL) model. The triple bottom line describes businesses that emphasize profit, people, and planet. According to the organization Canadian Business for Social Responsibility “businesses do better—by every measure—when they operate in a socially and environmentally responsible way.” Companies clearly need to remain profitable, yet many leaders realize sustainable profit can’t come at the expense of either people or the planet.

Hey, guess what? This isn’t some wishy-washy ploy to get you in the feels: we’re talking big name players that invest in corporate social responsibility (CSR) like 3M, Johnson & Johnson, Hewlett-Packard, Intel, and Microsoft.

Adaptability builds resilience that your customers notice. In short, all future-proofing strategies need to prioritize how you’re protecting your occupants—now, more than ever.

We’ve looked at benefits, now let’s look at some of the costs of inaction.

Seriously… Lawsuits Over Poor Indoor Air Quality?

Yep, they happen. Experts even predict a surge in workplace class-action lawsuits over unsafe working conditions in our post-coronavirus/COVID-19 reality.

When it comes to legislation for Canadian employers, the Canadian Centre for Occupational Health and Safety (CCOHS) states it’s an employer’s duty to provide good quality air as part of a safe and healthy workplace.

Lawsuits involving private sector buildings rarely disclose settlement amounts. While the numbers aren’t always visible, ASHRAE estimates lawsuits over indoor air quality (IAQ) during the early 2000s exceeded over $500 million annually. Individual settlements over indoor air quality have even exceeded $10 million, all the way up to $48 million. One settlement in Polk County, Florida exceeded the cost of the new building itself—all stemming from mold and moisture in the building’s envelope.

Depending where you are, not maintaining your heating, ventilation, and air conditioning (HVAC) systems can even land you on-the-spot fines and raise your insurance rates—as seen by our friends in Australia.

Don’t forget, bad publicity can also dismantle the company you’ve worked hard to build. It hurts your brand. It hurts your sales. If you think reputation management is a bunch of phooey, just ask the Beverly Hills Hotel, SeaWorld, Target, General Motors, Lululemon, McDonald’s, and American Apparel how bad publicity affected their businesses.

Social Costs of Poor Indoor Air Quality

Poor indoor air quality affects lives and livelihoods, which becomes more pressing when we look at the bigger picture.

Measured by labor and health care data, we can see the economic impacts of poor indoor air quality on occupants and businesses at a societal level. The case for indoor air quality (IAQ) at a national level is staggering.

We discussed stats around absenteeism for individual businesses, but lost labor also packs a hefty national price tag. According to Statistics Canada and other sources:

[ss_click_to_tweet tweet=”$8 billion a year in lost labor can be attributed to poor indoor air quality.  ” content=”$8 billion a year in lost labor can be attributed to poor indoor air quality.  ” style=”2″ link=”1″ via=”1″]

When it comes to health care, according to Statistics Canada and other sources:

16 Billion in lost labour and 228 billion spent on health care

[ss_click_to_tweet tweet=”Canadians are spending $34 billion a year in private health coverage due to poor indoor air quality.” content=”Canadians are spending $34 billion a year in private health coverage due to poor indoor air quality.” style=”2″ link=”1″ via=”1″]

What’s in our air that somehow adds up to $8 billion per year in lost labor and $34 billion a year in health care costs?

indoor air quality assessment tool

What’s Hiding In My Air?

To improve your indoor air quality, you need to know what you’re up against.

We categorize major indoor air pollutants as:

  • Biological (like bacteria, mold, pollen, and viruses like the coronavirus/COVID-19),
  • Chemical (like emissions from the outdoor environment and off-gassing from indoor sources), and
  • Particulate (like dust and smoke).

It turns out there’s a lot we can do to control and reduce these contaminants to make our facilities, buildings, and spaces safer.

We’ve discussed indoor air quality and why it matters. Next, we’ll discuss some of the common pollutants you need to know about, since each type may need different tactics.

Aside From The Coronavirus/COVID-19, What’s Hiding In My Air?

Indoor air quality discussions need to include the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) and the disease it causes (COVID-19).

This article covers indoor air quality as a whole—why it matters, what you need to know, and how to improve it. We’ve also prepared the following resources:

We wish good health to you and your loved ones.

—Your Gateway Team

Common biological air pollutants:

  • Bacteria (especially Legionella)
  • Pollen and dander
  • Mold and mildew
  • Viruses (especially the coronavirus/COVID-19)

Common chemical air pollutants:

  • Ammonia (NH3)
  • Carbon dioxide (CO2)
  • Carbon monoxide (CO)
  • Chlorine (Cl)
  • Formaldehyde (HCHO)
  • Ground-level Ozone (O3)
  • Hydrogen Sulfide (H2S)
  • Lead (Pb)
  • Nitrogen Dioxide (NO2)
  • Nitrogen Oxide (NO)
  • Radon (Rn)
  • Secondhand Tobacco Smoke
  • Sulfur Dioxide (SO2)
  • Volatile organic compounds (VOCs)

Size Matters: Particulate Matter Pollution (PMPs)

When it comes to particulate pollution, you may be hearing about PM2.5 and PM10. Those just mean the size of particles that sensors pick up, measuring their diameter in microns (AKA micrometers, µm, or a millionth of a meter).

The US Environmental Protection Agency (EPA) gives a great breakdown:

  • PM2.5 (fine particles): diameter smaller than 2.5 microns
  • PM10 (coarse particles): diameter 2.5 – 10 microns

These mostly come from incomplete combustion, car emissions, dust, and cooking, but can also come from chemical reactions in the air.

For a comprehensive list of measurable indoor air contaminants, consult Health Canada’s exposure guidelines.

Particle Sizes Indoor Air Quality Gateway Mechanical


How Do I Improve My Indoor Air Quality?

Different pollutants need different tactics. Indoor air quality (IAQ) testing shows you which specific pollutants and contaminants you’re up against.

The simplest, most comprehensive approach is to start with indoor air quality testing.

Some heating, ventilation, and air conditioning (HVAC) companies have the specialized equipment, training, and expertise to perform these tests. Contact your local HVAC service provider to find out more.

Before you do, please note that no indoor air quality test can detect viruses such as the coronavirus/COVID-19.

Indoor Air Quality free assessment tool

Can My HVAC System Improve My Indoor Air Quality?

The New York Times says “while dense urban conditions can aid the spread of viral illness, buildings can also act as barriers to contamination. It’s a control strategy that’s not getting the attention it deserves.”

So, let’s talk about this control strategy of putting your heating, ventilation, and air conditioning (HVAC) system to work for you.

Your heating, ventilation, and air conditioning (HVAC) system can mitigate and potentially eliminate many common air pollutants (such as the coronavirus/COVID-19) to improve your indoor air quality.

While indoor air quality tests currently available commercially may not detect viruses, you can still catch and neutralize them—using disinfection systems like plasma and UV.

HVAC technicians have many goals when designing and installing a new system.

Recalling the steps to improve your indoor air quality:

    1. Perform an indoor air quality (IAQ) test to identify pollution sources.
    2. Implement recommendations from the test results:
    • Remove indoor contaminant sources.
    • Rule out dirty/damp ventilation systems, and moisture in the building enclosure.
    1. Use your heating, ventilation, and air conditioning (HVAC) system to improve your indoor air quality. This section unpacks these HVAC system elements and their impact on indoor air quality:
    • Ventilation and dilution
    • Filtration and containment
    • Disinfection systems (UV and plasma)
    • Environmental controls (humidity and temperature)
    • Preventative maintenance


Ventilation & Dilution

Heating, ventilation, and air conditioning (HVAC) strategies involve bringing in clean air, containing and exhausting contaminated air, and diluting and filtering the air. We include more detail about this air purification process and how it relates to reducing disease transmission in our segment on air purification, HVAC, and the coronavirus/COVID-19.

ASHRAE Standard 62.1 sets the recommended minimum ventilation or air change rate at 5-20 cubic feet per minute, per person (2.5-10 L/second/person). The wide range owes to a space’s needs. For example, gyms and nail salons need higher ventilation rates, based on oxygen needs for higher activity levels and drawing out Volatile Organic Compounds (VOCs). Note these are minimum values—ventilation levels above these amounts improve indoor air quality and outcomes.

Special cases like labs and hospitals call for negative air pressure, meaning the ventilation system creates a vacuum. Sometimes, applications like multi-unit housing call for negative air pressure—preventing air from individual suites from contaminating shared hallways when doors open. These systems add an extra level of containment, but require floor-to-ceiling walls and doors which may not work in all settings.

Filtration & Containment

Filters remove most airborne contaminants and do the heavy lifting when it comes to cleaning the air. Depending on rating, filters trap and contain everything from larger particles like pollen and dust, to smaller particles like mold, bacteria, and insecticide dusts.

Filters are rated by their Minimum Efficiency Reporting Value (MERV), with higher numbers indicating their ability to catch smaller particles.

And remember: filter efficiency refers to the filter’s efficiency in taking particles out of the air—not to be confused with energy efficiency. Typically, higher efficiency filters (more effective at drawing out particles) actually draw a bit more power to operate.

For reference, here’s an overview of some average ranges:

  • Commercial buildings: MERV 7
  • Residential filters: MERV 8-13 or lower
  • Newer office buildings: MERV 13-14
  • Hospitals: MERV 13-16
Particles MERV Filters Capture Indoor Air Quality Gateway Mechanical
Particles MERV Filters Capture Indoor Air Quality Gateway Mechanical

Higher Minimum Efficiency Reporting Value (MERV) filters may require more space to house, plus stronger air-handling systems to accommodate the air resistance. As mentioned above, they may also draw more power to operate. While higher efficiency filters cost more, it’s understood that the resulting health benefits are dramatic.

As far as costs, one study estimates the costs/benefits as follows:

  • The annual per-occupant cost of filtration: $2.64,
  • The projected annual per-occupant economic benefits range from:
    • $45 (30% reduction in particles)
    • $90 (60% reduction in particles)
    • $135 (90% reduction in particles)
  • In short: the benefits of increased filter efficiency can outweigh the costs by over 50 times.
Filtration Costs Benefits Indoor Air Quality Gateway Mechanical

There’s a trade-off for increased filter efficiency—higher efficiency filters may be more costly, use more energy, and affect operations. They can trap quite a lot of junk that you don’t want in your lungs—but you need to know that even the really good ones still miss a fair bit. High Efficiency Particulate Air (HEPA) filters trap up to 99.97 percent of particles down to 0.3 microns. That’s incredibly efficient, but there’s still a likelihood that particles as small as the coronavirus/COVID-19 can pass through.

Often, even high efficiency filters are not enough on their own. This is where disinfection comes in: they can increase your existing filter’s efficiency and even neutralize biological pathogens.

Disinfection and improving your indoor air quality: UV & Plasma

You can put your heating, ventilation, and air conditioning (HVAC) system to work in neutralizing viruses (like the coronavirus/COVID-19), biological pathogens, and other pollutants. Disinfection significantly reduces potential exposure and improves indoor air quality for yourself and your occupants.

Short version: plasma traps viruses, UV neutralizes them.

How Plasma Works to Improve Indoor Air Quality

Plasma (AKA ionization and cold plasma bipolar ionization) acts on the ambient air in the room by releasing ions into the room that latch onto biological pathogens. It works through two main principles. First, it deactivates viruses through a chemical reaction on their cellular membranes. Second, it works by agglomeration—fancy way of saying plasma ionization lumps small particles into larger ones. These larger particles increase filter efficiencies by increasing how much your filter traps.


Airborne particles are charged by the
ions causing them to cluster
and be caught in filters


As they divide to reproduce, bacteria
and virus cells bond with oxygen
ions and are destroyed


Odorous gases and aerosols oxidize
on contact with oxygen ions
and are neutralized


Oxygen ions cause a chemical reaction
with VOCs breaking down
their molecular structure

How UV Works to Improve Indoor Air Quality

UV destroys viruses (including influenza), neutralizing up to 99.9% of microbes in a first pass. There are also several types of UV in use for air purification. For example, UVC neutralizes biological pathogens, and UVV eliminates other pollutants—including secondhand smoke and Volatile Organic Compounds (VOCs). Heating, ventilation, and air conditioning (HVAC) UV systems operate in the ductwork, so you don’t have to worry about exposure. Wanna learn more about how UV disinfection works in your HVAC system? Check out this free webinar on HVAC and air purification.

You can also combine these options. A popular approach is to have the plasma ionizer acting directly on the air in the room, while the UV system neutralizes anything that’s pulled back up into the ductwork.

Talk to your local HVAC representative today to discuss which disinfection options would work best for you and your occupants.

Environmental Controls

The American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) has long recommended that keeping indoor humidity at a moderate range of 40 to 60% for human health. Most heating, ventilation, and air conditioning (HVAC) help maintain this level of humidity.

We discussed productivity earlier and found temperature isn’t just a superficial comfort. Temperature directly affects productivity. Take 22-230C (71-740F) to be the optimum indoor temperature. For every 0.50C (10F) deviation from that optimum temperature, productivity decreases by 2%.

If we start with the average Canadian hourly wage of $27.83, with 2 weeks off a year:

  • 50C (10F) deviation = 2% productivity decrease
    • = losing $0.55/hour, $4.40/day, $22/week, $1100/year per person
  • 10C (20F) deviation = 4% productivity decrease
    • = losing $1.11/hour, $8.88/day, $44.40/week, $2,220/year per person
  • 20C (40F) deviation = 8% productivity decrease
    • = losing $2.23/hour, $17.84/day, $89.20/week, $4,460/year per person

In short: even a degree or two away from optimal temperatures costs big money.

Temperature Costs Productivity Indoor Air Quality Gateway Mechanical


Keeping Your HVAC Running: Reduce Downtime and Costly Repairs

Make sure your system is running properly, so the work you’ve done isn’t wasted.

For the best indoor air quality, ensure heating, ventilation, and air conditioning (HVAC) systems receive scheduled maintenance.

Pennies are tight for most of us (now more than ever) but remember the adage: “an ounce of prevention is worth a pound of cure.”

Preventative maintenance helps identify problems before they happen—keeping your organization running without service disruptions. Preventative maintenance also makes sure you have what you need before you hit crisis mode.

Supply chain interruptions make planning preventative maintenance and pre-ordering parts more relevant than ever.

Speaking plainly, scheduling maintenance helps you avoid downtime and reduce or avoid costly repairs, driving down your costs overall. Running equipment that’s overdue on repairs wears out your equipment faster and also costs more in energy consumption. For example, you’ll save 5 to 15% on energy with optimal filter changes (US Dept of Energy).

No matter who your local HVAC service provider is, we always recommend scheduling preventative maintenance.

Here’s an indoor air quality flowchart from the Canadian Centre for Occupational Health and Safety (CCOHS). It’s a great tool to help you navigate the process of improving the indoor air quality in your facility, building, or space.

Summing It All Up: Why Indoor Air Quality Matters

Words fall short in describing the challenges we’ve collectively experienced this year. People are expecting more of how their spaces attend to their health—and indoor air quality is the single largest determining factor.

Focusing on what we can control is how we empower ourselves and climb out of this together.

We can:

  • Improve indoor air quality for safer facilities, buildings, and spaces,
  • Minimize risks and prioritize our occupants’ health, and
  • Do our part to help slow the spread of the coronavirus/COVID-19.

Why Indoor Air Quality Matters

If you’ve followed along, we’ve already unpacked in detail why indoor air quality matters. Here’s a quick recap, in case you missed it:

Good indoor air quality increases occupant health and experience in the space, increases performance and productivity, lowers turnover and absenteeism, optimizes returns on your investments (ROI), and boosts your triple bottom line.

Poor indoor air quality harms occupant health and experience in the space, lowers performance and productivity, increases turnover and absenteeism (lowering occupancy and rents), risks lawsuits, fines, and bad publicity, and costs economies billions of dollars in health care and lost wages.

Action Items for Improving Indoor Air Quality

Ensuring you have the best indoor air quality (IAQ) is an important part of following through on your safety promise to yourself and your occupants.

Recommended steps:

  1. Perform an indoor air quality (IAQ) test to identify pollution sources.
  2. Implement recommendations from the test results:
    • Remove indoor contaminant sources.
    • Rule out dirty/damp ventilation systems, and moisture in the building enclosure.
  3. Use your heating, ventilation, and air conditioning (HVAC) system to improve your indoor air quality.
    • Ventilation and dilution:
      Confirm ventilation rates are a minimum of 5-20 cfm/person, depending on space usage.
    • Filtration and containment:
      Check filter efficiency and function, increase Minimum Efficiency Reporting Value (MERV) if possible—and within the limits of your heating, ventilation, and air conditioning system.
    • Disinfection systems:
      Consider adding UV and/or plasma disinfection systems.
    • Environmental controls:
      Aim for humidity of 40-60% and a temperature of 22-230C (71-740F).
  4. Schedule routine air quality testing and preventative maintenance for your heating, ventilation, and air conditioning (HVAC) system.


We hope this guide helped you better understand indoor air quality and gave you actionable takeaways.

Now we want to hear from you.

Which tip from this guide do you think will help you the most?

Are you planning testing your testing your indoor air quality soon to understand what’s happening in your space?

Whatever you do next, we’d love to hear from you by leaving a comment below right now.

Thanks for doing your part to improve the safety of your facilities, buildings, and spaces!

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