Commercial buildings pose unique challenges when it comes to ensuring indoor air quality because their HVAC needs are usually dominated by cooling. That means a lot of attention goes into how ventilation helps with cooling. But as researchers turn their attention to IAQ, they’re saying building operators should look beyond ventilation because there are other ways to improve air quality.
“If you're just recirculating the air inside a building, you're just getting more and more human-associated microbes, and some of those are good, but many of those are bad,” Jonathan Eisen, an evolutionary biology professor at the UC Davis Genome Center, said in a UC Davis Health blog post.
Scientists have had success with alternatives to ventilation to improve air. One method is using germicidal ultraviolet, or GUV, technologies.
At the ASHRAE Annual Conference, researchers for the U.S. Department of Energy’s Pacific Northwest National Laboratory provided an overview of the technology. They showcased three types of GUV technologies that could help to reduce airborne disease transmission and achieve targets set by ASHRAE and the Centers for Disease Control and Prevention.
GUV technology was shown to provide “substantial contributions” to equivalent clean airflow, or the flow rate of pathogen-free air that is distributed uniformly within a space or system, when calculating compliance with ASHRAE Standard 241’s requirements, Belal Abboushi, lighting research engineer at PNNL, said in his presentation at the conference.
IAQ, efficiency trade-off
Optimizing and supplementing ventilation remains a key way to improve air quality but operators struggle with ways to do that without sacrificing efficiency.
Although all airborne pathogen mitigation measures could meet ASHRAE Standard 241 guidance equivalent clean air metrics, Cary Faulkner, a mechanical engineer at PNNL, said at the ASHRAE conference, increasing outdoor air ventilation led to a 73% increase in energy use.
The way manufacturers have tried to make HVAC systems more efficient has contributed to the challenge of solving for IAQ, Chris Cappa, professor and chair of the Department of Civil and Environmental Engineering at UC Davis, said in the UC Health blog post.
“In particular in larger buildings, HVAC systems have been designed over many decades to minimize energy use, with much less consideration for indoor air quality issues,” he said.
The effort to improve air quality could get a boost from the federal government.
Last year, two bills were introduced in Congress that highlighted the rising focus on IAQ among legislative leaders. These include the Indoor Air Quality and Healthy Schools Act and Airborne Act — which sought to expand the U.S. Environmental Protection Agency’s Indoor Environments Division, establish a list of significant indoor contaminants and voluntary guidelines for reducing the risk of exposure and provide tax credits for indoor air quality assessments.
Researchers say they’ve been seeing more interest in tackling air quality since the COVID-19 pandemic brought the problem of microbes in the air to everyone’s attention.
“We're exposed to things where we are, and we spend more time indoors than we do outdoors,” Deborah Bennett, professor in public health sciences and at the UC Davis Environmental Health Sciences Center, said in the blog post.
IAQ in decision-making
It’s not impossible to improve indoor air quality while also improving energy efficiency, but operators must be intentional about decision-making, according to experts from ASHRAE, the U.S. Green Building Council and the International WELL Building Institute. They shared their ideas last year in a National Institute of Building Sciences webinar.
For example, operators can right-size outdoor air filters, implement demand-controlled ventilation, adopt displacement ventilation and use ultraviolet irradiation to combat mold growth in central air handling units, according to information presented in the webinar.
Based on recent announcements, manufacturers are coming up with solutions that help, too. One example is from HVAC manufacturer Air2O, which has partnered with PuriFi Labs to provide whole-building air and surface purification to data centers, healthcare facilities and battery and semiconductor manufacturing facilities, the companies announced in February. The companies say they’re using their technology to neutralize within the HVAC system airborne pathogens and eradicate the particles they travel on.
Smart indoor air quality services have also introduced tools to promote healthy buildings. These tools allow facilities leaders to maintain optimal building environments while focusing in-house resources on core operational activities, Siemens says in a whitepaper.
Operators can also also lean on automation through building management systems (BMSs) to help optimize building HVAC. The automation can help the systems manage ventilation, helping to ensure fresh air is circulating and humidity levels are right. That contributes “to reduced pollutants and allergens,” Scott Huffmaster, vice president and general manager of smart services for commercial HVAC at Trane Technologies’ North America segment, told Facilities Dive.
“A BMS can tweak temperature and lighting based on real-time data and what people prefer,” he said, “making the environment more pleasant and productive.” The AI-driven developments also enable systems to enhance IAQ by monitoring ventilation continuously and making adjustments as needed to keep conditions ideal.
