MRO Magazine

Indoor Air Quality

Indoor air quality has never been more important than this past year with initial findings and the belief that COVID-19 was an airborne virus.

Health & Safety

September 14, 2021
By Mariete F. Pacheco

Photo: © Maridav / Adobe Stock

According to the United States Environmental Protection Agency (EPA), the quality of the air indoors can be two-to-five times more polluted than the outdoors. This can be a significant concern in many facilities, as employees start to return to work this coming fall.

The air quality in commercial spaces is believed to have deteriorated over the past few decades due to several factors, including; the increased use of synthetic building materials, improper ventilation (few commercial spaces have windows which can be opened), poor building design, such as improper placements of thermostats and humidity controls, increased use of products containing and off-gassing volatile organic compounds (VOC) or ozone, such as computers, adhesives, carpets, cleaning supplies and photocopy machines and more tightly sealed buildings in the quest for creating energy efficient buildings.

To determine if your facility is at risk of poor indoor air quality, there are some considerations both from a team member perspective as well as a physical environment perspective. For team members, review if there has been an increase in absenteeism due to health issues, in particular respiratory concerns, including allergies, may be associated with “sick building syndrome”, which can impact productivity as a result of poor indoor air quality.

Considerations regarding the physical environment of the facility include factors such as: increased dust or dirt on work surfaces, unusual deterioration of equipment or furnishings, inconsistencies in the air distribution (hot spots VS cold areas,) and mildew or mold growth.


Source of pollutants affecting indoor air quality can come from both indoor sources as well as outdoors. Indoor pollutants such as combustible sources, should be reviewed, like wood, coal or oil heating sources, which can release harmful combustion byproducts. They include particulate matter and carbon monoxide into the building or the use of older equipment or supplies which may contain VOCs or harmful chemicals, such as formaldehyde or other toxic materials.

Outdoor sources of pollutants may enter the facility through open entrances or exits, or in many instances from the shipping and receiving department’s large bay doors. Other outdoor pollutants may enter a facility through cracks in the facility. Such can be the case for radon or from chimneys, which may allow smoke to re-enter the building, especially on windy days.

There are several ways to combat and improve your facility’s indoor air quality, but first it is important to determine if there are air quality concerns that exist.

Having a professional test, the air quality throughout the facility not only helps to identify the existence of an issue, but also helps to determine if there are contained areas of the facility which can have targeted solutions applied as compared to large-scale facility-wide solutions that can generally be costlier to implement.

Plus having a professional measure, the air quality provides a benchmark to compare to after implementing air quality solutions to ensure they are addressing your problem areas. A professional may test for a variety of contaminants and issues including air flow, ventilation, gaseous sampling, micro biological matters such as bacteria, mold or fungi, and air testing for airborne particulates or toxic gases such as carbon monoxide or nitrogen dioxide. Sometimes testing will include short-term monitoring over a period of several days to help establish a baseline and to rule out operational impacts, like if temperatures or carbon monoxide swing greatly in certain areas during limited time periods of the facility due to increased employee presence. For example, in the break room during lunch, or boardroom during staff meetings.

There is an array of indoor air quality solutions to fit a variety of budgets and applications, including portable solutions that can be moved from area to area in a facility offering a more targeted approach and more permanent solutions which affix to the existing HVAC system and address the entire space serviced by the HVAC system.

Air purification systems including electrostatic or electronic air cleaners, HEPA filters, plasma systems and UV technology are the most commonly available in the market. Electrostatic or electronic air cleaners are installed at the source of a forced-air system and operate with a low-level static pressure drop.

Essentially, any dirt or dust that passes through its filtration system is electrocuting it and stops it from passing through the remaining HVAC system. It prevents the spread of it throughout the facility via the ductwork. HEPA filters (high-efficiency particulate air or absorbing) trap air contaminants in its complex web of fibres; from larger to smaller particles as the filter material changes in density and construction. Some HEPA filters offer enhanced protection through the use of an ionizer, which first charges particles as they pass through with a negative electrostatic charge.

Heat Recovery Ventilators (HRV) is an air exchange system that helps to enhance the indoor air quality by introducing outdoor air into the facility and transferring heat. HRVs are commonly used in environments where high humidity is a major concern in the winter. In addition, HRVs tend to have a smaller footprint, making them ideal in smaller facilities. For tightly sealed building envelopes, HRVs are the preferred solution, as humidity will more likely stay indoors.

Energy Recovery Ventilator (ERV) is a mechanical air exchange system that also combines outdoor air into the stale indoor air. However, it offers the added functionality of transferring both heat and moisture. Since ERVs transfer moisture, they can prevent dryness during the cold months while reducing air conditioning demands in the summer months. ERVs are usually reserved for use areas where humidity extremes need to be moderated throughout the year or for colder climates.

HRV and ERV are similar pieces of equipment which introduce fresh outdoor air into the facility, and exhausting stale air out of the facility, while also recovering energy from the exhausted air simultaneously. Both maintain a continuous supply of fresh air from the outdoors and provide an energy-efficient method of exhausting potentially harmful indoor pollutants to improve the indoor air quality. The main difference between an HRV and ERV is that the HRV transfers only heat as compared to the ERV, which transfers both heat and moisture.

Portable air disinfection units are also available and can be used to address smaller areas, which offer flexibility if there are limited areas within the facility with poor air quality, instead of being prevalent throughout the facility. There are a variety of portable solutions that use diverse options such as UV lights, carbon filters or specialized coils surrounded by atmospheric plasma discharge, which provides a powerful strike that inactivates airborne pathogen cells.

Lastly, there are general maintenance solutions that can also assist in improving a facility’s indoor air quality, including regularly changing filters in the HVAC system, performing regular preventative maintenance on the HVAC system to ensure it is operating at peak performance and is not contributing to poor air quality by spreading odours and regularly cleaning ducts. In addition, it is critical to maintain general equipment in the facility to ensure it is not contributing to airborne pollutants, such as leeching fumes, smoke or other harmful chemicals, such as oil or natural gas.

Managing indoor air quality is paramount in maintaining the health and wellness of employees. There is no greater time than now with the ongoing COVID-19 concerns, especially as employers plan to welcome employees back this fall. Indoor air quality can be improved through a host of mechanical system upgrades to improve ventilation through the facility, such as adding HRVs and ERVs, but as well through less costly approaches, such as conducting regular equipment maintenance. Indoor air quality is vital to all organizations regardless of the industry, especially since employees spend the majority of their time indoors. MRO
Mariete F Pacheco, MBA, PMP, Managing Director, FRW Services Inc. has over 15 years of procurement and supply chain management experience across a variety of industries including industrial, construction, retail and more.