The Path to Better Indoor Air Quality-- Improved Monitoring for CO2 Ventilation and More
Getting back to workplaces, restaurants and schools goes beyond the simple reopening of buildings; it involves innovative solutions to provide appropriate air quality monitoring, ventilation and filtration.
- By Mary Furto
- Oct 01, 2021
Whether you have employees returning to in-person work or students going back to in-person learning, monitoring and maintaining indoor air quality (IAQ) is critical. More people are paying attention to air quality in the spaces we use for work, school, entertainment and travel, and building owners are looking for ways to create cleaner air to instill occupant confidence.
According to a 2021 Honeywell survey, data shows that the COVID-19 pandemic will likely have a lasting impact on facility management and operations. Seventy-five percent of surveyed U.S. facility managers indicate that COVID-19 prompted their facility to rethink its modes of operation. COVID-19 is also driving facility managers to adjust their priorities and investments. For example, 62 percent are more likely to invest in indoor air quality optimization and other healthy building solutions than in pre-pandemic times. Getting back to workplaces, restaurants and schools goes beyond the simple reopening of buildings. It involves innovative solutions to provide appropriate air quality monitoring, ventilation and filtration.
The Importance of Good Air Quality
All over the United States, decision makers are taking steps to make evidence-based, long-term improvements to IAQ to help reassure people that they have taken steps to make their spaces safer, not only to reopen public spaces responsibly, but also to keep them open.
Environmental Protection Agency (EPA) studies consistently show that indoor air pollution ranks among the top environmental risks to public health and indoor levels of pollutants may be two to five times higher than outdoor levels. As the colder fall and winter months are ahead of us and more people will rely on indoor gathering spaces rather than outdoor, it is important to look into ways to improve IAQ.
Types of Pollutants Found Indoors
According to the EPA, there are a wide range of pollutants found indoors, including:
- Germs, viruses and airborne microbes
- Dust and dander
- Mold and mildew
- Volatile organic compounds (VOCs)
Risks of Poor-Quality Indoor Air
The effects of poor IAQ in indoor settings is not a new phenomenon; the impact of COVID-19 brought it to the forefront. A recent study by Harvard T.H. Chan School of Public Health shows that poor IAQ, coupled with high CO2 levels and low ventilation rates, may dull cognitive abilities making it harder to remain alert. Indoor air pollution can also impact occupant wellbeing, including coughing, shortness of breath or aggravating asthma: eye, nose and throat irritation, headaches and allergic reactions. It can even potentially increase the risk of spreading some airborne viruses. Buildings with outdated HVAC and ventilation systems can foster environments where the risk of airborne virus transmission could increase, so deploying strategies to help improve indoor air quality is a key step to healthier places of work, school and leisure.
Maintaining good indoor air quality
Proper ventilation and good air flow can also help to make a more productive environment. There is not one solution to solving indoor air quality – it takes a layered approach looking at ventilation, fresh air intake, pressure, humidity, temperature and filtration.
When thinking about the ways in which IAQ can be addressed, here are three steps to consider:
Continuously Monitor CO2. When it comes to air quality monitoring, sensing technology is an important tool to identify opportunities for indoor air quality adjustments. IAQ sensors that monitor a building’s environmental state and air quality status offer an effective, automated solution. The concentration of CO2 indoors is one indoor air quality parameter to consider and might indicate when additional fresh air intake is needed. By having a constant check on the concentration of CO2 indoors, it can help when deciding whether to adjust the amount of outdoor air delivered into a space.
In order to keep track of indoor air quality, CO2 monitoring products are useful tools as they can provide information that can be used to analyze the quality of air inside enclosed spaces. Research conducted by scientists at the University of Coloradohas shown that real-time monitoring of indoor ambient air can be an indicator of potential increased risk of some airborne viral transmissions, using different levels of risk-based factors, including for example CO2 concentration levels and the type of human activity in the area. CO2 levels can be used as a reference point for exhaled air and, when coupled with other factors and parameters, can be part of an indicator of the risk of potential exposure to some airborne viral transmissions. Effective monitoring solutions of CO2 levels can be combined with other factors and used as an indication of when conditions may be present that could increase the risk of potential exposure to some viruses.
Based on CO2 measurements and occupancy levels, the intake of outdoor air can be adjusted and increase the flow of air indoors. A target benchmark for good ventilation of CO2 readings should be set below 800 parts per million (ppm). This approach requires periodic measurements of the CO2 level, comparison with the benchmark and adjustment decisions based on these and other relevant parameters that vary depending on each individual application.
By monitoring for CO2 levels in enclosed spaces, building occupants can use the information as an indication of when conditions may be present that could increase the risk of potential exposure to some airborne viral transmissions and can use that and other relevant parameters to take any actions they deem appropriate, like increasing ventilation in a space.
Provide Adequate Ventilation. Proper ventilation of indoor spaces helps maintain a healthier environment. According to studies and guidelines from government agencies including the Centers for Disease Control and Prevention (CDC) and the EPA, proper ventilation and filtration are effective ways to help reduce or remove unwanted particles including pathogens, pollutants and other irritants from the air. Outlined below are some recommended ventilation interventions from the CDCthat can help improve IAQ.
Manage Temperature and Humidity. Air quality strategies should also include steps to manage temperature and humidity. In many cases, the optimal range for humidity is around 40-60 percent, as this is where the communication of viral pathogens is at its lowest.12 It is more difficult to control the spread of potential infections in excessively dry conditions. On the other hand, excessive humidity promotes the growth of dust mites and fungi, which are known to exacerbate respiratory conditions and allergies.
- Increase fresh air intake. Adjust mechanical systems to allow for the maximum fresh air intake and for buildings without mechanical controls, open windows and doors to bring outside air indoors, when outdoor conditions allow.
- Maximize ventilation. Adjust building controls to increase airflow throughout the building.
- Improve filtration systems. Improve air filtration with MERV13 filters or higher. There are even air filters in development with chemical bonding technology that can capture and inactivate up to 97 percent of the SARS CoV-2 virus that causes COVID-19. Condition-based maintenance software can monitor particulate matter and volatile organic compounds to identify if filters require changing based on need versus a maintenance schedule to avoid costly, unnecessary filter changes.
- Check current exhaust ventilation systems. For rooms where exhaust fans are used regularly, such as restrooms, kitchens and labs, make sure the fans are fully functional and are turned on any time the space is in use. Additionally, air should flow toward the exhaust intake to support the elimination of any pollutants.
If left unattended, moisture can lead to mold growth, which can, in turn, lead to allergic reactions, such as sneezing, runny nose, red eyes and skin rash. If excess moisture does lead to mold in an indoor space, actions should be taken promptly to remediate the issue. If mold is suspected in an HVAC system, do not run the system until cleaned because it could spread throughout and consequently contaminate the building. Lastly, effective personal protective equipment should be worn when dealing with mold, such as well-fitted N95 respirators, to avoid breathing in tainted air.
Today, more than ever, people are concerned about their health and safety in the buildings in which they work, learn, eat or shop. Taking actions to ensure good indoor air quality is paramount in helping individuals restore confidence in their safety as people get back to indoor activities.
The answer to better indoor air quality is to take a layered approach. There is not one solution; it is working to combine many factors to help improve indoor air quality. It does not always have to be a complicated process of ripping out old equipment and starting from scratch. Depending on the need, it can be a straight-forward HVAC upgrade with modifications or adding specific CO2 monitoring solutions that can help users know when to address concerns and take actions. A well configured Building Management System and air quality sensing technology can give building operators better insight to help them create a cleaner and healthier built environment.
This article originally appeared in the October 2021 issue of Occupational Health & Safety.