Indoor Air Quality Awards

These awards help the public easily identify facilities that provide clean, healthy air. They also help building owners demonstrate what they’re doing to keep occupants safe. Any space presenting at least a Bronze-level award demonstrates indoor air quality leadership and provides you with the safest possible indoor air.

Gateway Mechanical Services Inc. created these awards, based on indoor air quality standards as outlined by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) and the International WELL Building Institute (IWBI).

Various additional authorities consulted include: the American Conference of Governmental Industrial Hygienists (ACGIH), Canadian Centre for Occupational Health and Safety (CCOHS), Environmental Protection Agency (EPA), Health Canada, the American Society for Microbiology (ASM), the Mayo Clinic, and the National Institutes of Health (NIH).

Determining compliance to indoor air quality standards requires measurements provided through annual indoor air quality testing, with either Gateway Mechanical or another certified independent provider.

Awards must be reassessed annually because good indoor air quality requires ongoing maintenance and monitoring.

These awards are currently only available in Western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba). Please contact us if you’re interested in certification outside of this area.

The awards levels are determined by measurable clean air standards with actionable objectives. Each level is based on HVAC industry best practices for ventilation, filtration, maintenance, environmental comfort, disinfection, and real-time indoor pollution monitoring.

Each condition affects the indoor air ecosystem:

• Proper ventilation dilutes and exhausts contaminants, including gases, volatile organic compounds (VOCs), biological pathogens, and viruses.
• Superior filtration purifies the air by physically trapping biological pathogens and particulate pollution.
• Optimal maintenance ensures systems perform as intended and reduce energy consumption.
• Environmental controls like humidity and temperature directly affect your health and comfort. The right balance protects you against biological contaminants—including bacteria and viruses.
• Active disinfection describes ultraviolet germicidal irradiation (UVGI) and plasma ionization. These actively disinfect the air to slow the spread of airborne pathogens and viruses.
• Indoor air quality monitoring gives real-time alerts—and automatically corrects issues like indoor pollutants and ventilation levels.

a) Carbon dioxide (CO₂) levels <1090 ppm

(American Society of Heating, Refrigerating and Air-Conditioning Engineers; ASHRAE Standard 62.1- 2016)

When a space is at average/high occupancy, lower levels of CO₂ confirm adequate ventilation—which brings fresh air in and dilutes contaminants and pathogens in the air.

People exhale 0.3 litres of CO₂ per minute, so it builds up in spaces without enough ventilation. Moderate levels may not be toxic but affect human health and reduce productivity. High levels of CO₂ highlight improperly ventilated spaces and potential issues with indoor combustion sources (like boilers). Outdoors, CO₂ comes from vehicles and power plants, and high outdoor levels affect what’s indoors. That’s why CO₂ needs to stay at less than 700 ppm above outdoor CO₂ concentrations—meaning it can’t be too much higher than outdoor levels. The outside air level is typically 390–400 ppm, therefore indoor CO₂ levels should not exceed 1090 ppm.

b) Carbon monoxide (CO) levels <9 ppm

(U.S. Environmental Protection Agency National Ambient Air Quality Standards, 2012)

CO is a toxic gas you can’t smell or see. It also comes from incomplete combustion, like vehicle exhaust, leaking chimneys, furnace backdraft, wood stoves, and gas powered equipment like generators and space heaters.

c) Particulate Matter concentrations

PM_2.5 <15 µg/m³ (US EPA NAAQS, 2012)

PM₁₀ <50 µg/m³ (World Health Organization Air Quality Guidelines, 2005)

Particulate matter refers to solid, liquid organic, and inorganic substances suspended in the air. PM_2.5 and PM₁₀ describe the size of particles that sensors pick up, measuring their diameter in microns (µm).

• PM_2.5 (fine particles): diameter smaller than 2.5 microns, such as sulfates, nitrates, ammonia, carbon, lead, and organics
• PM₁₀ (coarse particles): diameter 2.5 – 10 microns, such as soil, dust, sea salt, and bioaerosols

These mostly come from incomplete combustion, car emissions, dust, and cooking, and chemical reactions in the air. The smaller the particle, the deeper they go into our lungs and bloodstream. They cause and worsen heart and lung diseases, and can lead to hospitalization and premature death.

For comparison’s sake, droplets carrying virus particles are generally about 10 microns and up (PM₁₀), and unattached virus particles (from evaporated droplets) are typically smaller than 0.3 microns (less than one tenth the size of PM_2.5).

d) Total volatile organic compounds <500 µg/m³ (TVOCs)

(US Green Building Council, LEED v.4, 2013)

Toxic chemicals are in almost every built space and they inevitably make it into our air.

Common sources are paint, varnish, glue, flooring materials, air fresheners, cleaning products, and new furnishings—many of which off-gas and leak cancer-causing VOCs like formaldehyde into your air for years. They also come from cooking and burning wood indoors without an exhaust system, and leaky oil and gas burning furnaces.

Lead-based paint, asbestos, and heavy metals are carcinogenic, cause organ failure, and damage your nervous system. They’re banned now but are common in older construction—and released into your air through wear, tear, and renovations. Did you know asbestos wasn’t officially banned in Canada until 2018? It’s in insulation, ceiling and floor tiles, cement and plaster in buildings older than 1980, and especially before 1960. Even construction as new as 2006 often has heavy metals in paints.

Direct outdoor sources spread VOCs into indoor air. Pesticides, herbicides, and fertilizers used near your building get tracked into and through your space and air. Another common source is improperly placed air inlets near parking garages, loading docks, and smoking exits that bring carcinogenic second hand smoke and vape emissions directly into the space.

Industrial chemicals in your space also have maximum allowable amounts—though they’re typically only measured either in industrial settings, or when a problem’s suspected. While formaldehyde is included in total volatile organic chemical (TVOC) counts, some cases do call for independent tests. Here are the short-term exposure limits for common industrial chemicals:

• Ammonia (NH₃): <35 ppm
  (American Conference of Governmental Industrial Hygienists; ACGIH)
• Chlorine (Cl): <1 ppm
  (ACGIH)
• Hydrogen sulfide (H₂S): <5 ppm
  (ACGIH)
• Formaldehyde (HCHO): <27 ppb
  (World Health Organization, Guidelines for Indoor Air Quality, 2010)
• Nitrogen dioxide (NO₂): <100 ppb
  (US EPA NAAQS, 2012)
• Ground-level ozone (O₃): <51 ppb
  (World Health Organization, Guidelines for Indoor Air Quality, 2005)
• Sulfur dioxide (SO₂): <0.25 ppm
  (Occupational Safety and Health Administration, Standards - 29 CFR)

To qualify, you must complete an Indoor Air Quality Test for the current calendar year, with either Gateway Mechanical or another certified independent provider. The test must include the specific parameters listed above.

These costs cover the administration involved in reviewing and processing the application to determine if the applicant meets the requirements necessary to be awarded the appropriate certification level. These administrative steps are in place to uphold accountability, integrity, and consistency across the certification and awards levels.

Please note, the administration costs for either air test certifications or awards nominations DO NOT include the cost of air quality testing. Indoor air quality testing costs from any provider will vary, depending on space size and individual requirements.

Numerous measurements relate to air speeds, including air balance, air distribution, and air flow. For example, air distribution describes air intake, flow, and exhaust levels. Air balance refers to achieving a specific system wide airflow level.

Some cases do call for these measures that require more extensive, holistic measurements.

For example, according to ASHRAE standards, depending on space usage, ventilation rate should always be a minimum of 5–20 CFM/person. To reduce transmission risks in pandemic conditions, it’s recommended that ventilation rate remain below 40 CFM/person. However, because these measurements often require extensive labour and calculations, they’re not always feasible unless a problem is suspected.

CO₂ levels are widely used across the industry to indirectly determine whether or not a space is adequately ventilated, at a fraction of the cost.

In each case, the awards also outline the ideal filtration level, but only for systems that can support it. Always ensure filter efficiencies remain within system limits. Using the wrong filter can void equipment warranties, create bypasses where air goes around (instead of through) the filter, create undue strain on mechanical equipment—and even negatively impact your equipment’s life span, how it operates, its effectiveness, and your energy bill.

As far as the numbers, note that anything MERV below 8 will barely catch anything as small as human hair. MERV 8 catches approximately 70% of particles 3–10 µm—that’s only 70% of anything as small as mold spores, dust mite body parts and droppings, cat and dog dander, hair spray, fabric protector, dusting aids, pudding mix, and powdered milk (and nothing smaller).

New construction and retrofits generally start at about MERV 13, but it’s crucial to always check filtration limits before installation.

In short, like with any dynamic system, proper HVAC upkeep ensures peak performance—and sub-optimal maintenance quickly and dramatically reduces indoor air quality.

Get in touch with your local HVAC service provider to learn more about how maintenance programs are structured and the benefits of regularly scheduled maintenance.

Active disinfection describes ultraviolet germicidal irradiation (UVGI) and/or plasma ionization. These processes actively disinfect the air to slow the spread of airborne pathogens and viruses, and can even be used in tandem.

Research shows UV neutralizes 99.9% and plasma ionization neutralizes 99.4% of biological pathogens.

If you’d like to learn even more about these technologies, please visit the disinfection section in our Indoor Air Quality Guide.

We use this as a shorthand to describe a common feature within a Building Automation System (or a Building Monitoring System). These monitor and control multiple systems within a building, such as lighting, ventilation, fire systems, and security systems. Indoor air quality monitoring gives real-time alerts—and automatically corrects issues like indoor pollutants and ventilation levels. For more about these systems, check out Your Building Automation System Essential Guide: How It Works & Why You Need One.

These additional measures affect occupant health and comfort.

As far as the maximum limit, studies show elevated humidity worsens perceptions of indoor air quality. Relative humidity levels >65% also promote growth for mold, microbes, and pests like dust mites.

According to ASHRAE (Standards 55-2013 and 62-2016), there aren’t established lower humidity limits for thermal comfort. However, ideal relative humidity levels for indoor comfort tend to fall in a range of 30–50%. At a minimum, the National Library of Medicine suggests a humidity of at least 40% helps your eyes, skin, airways—and helps you fight bacterial and viral infections. The right humidity balance boosts your immunity against biological contaminants—such as bacteria and viruses. A recent study showed the coronavirus/ COVID-19 deactivates fastest on surfaces at 50% relative humidity.

ASHRAE Standard 55-2013 suggests maintaining an indoor temperature of 20 – 26°C (68–79°F). Preferences vary, but this range tends to be most comfortable, with 23°C (74°F) as a happy medium for most. Every space in your building should ideally be comfortable and properly balanced so you don’t find spots where it’s too cold, drafty, or too hot.

The people at Harvard have been studying how to make healthier buildings for over 40 years. They list temperature as one of the nine foundations of a healthy building. Temperature often compounds other indoor environmental problems—for example, high temperatures increase building material off-gassing, releasing irritating and toxic chemicals, like volatile organic compounds (VOCs) into the air.

Many people only consider temperature in terms of comfort, but it also directly affects productivity. If your temperature is outside the optimal range of 20–26°C (68–79°F), for every 0.5°C (1°F) away from comfort, productivity decreases by 2%. So, for every degree away from comfort, if you take the average Canadian hourly wage, then a 2% drop in productivity can cost a business $4,200/year/person.

Adjusting to seasonal climates reduces utility costs and is often more comfortable than the jarring indoor/outdoor temperature swings. In the winter, aim for 20–24°C (68–75°F) and in the summer, aim for 24–27°C (75–81°F).