Why IEQ matters beyond basic comfort

In the simplest of terms, indoor environmental quality (IEQ) is the quality of a building’s environment in relation to the health and well-being of its occupants. It includes design that keeps in mind elements such as air, light, acoustics, temperature, and even aesthetics. And as simple and obvious as these elements seem, when you start to think about the ripple effect of how they impact occupants in a building, it starts to become clear how complex and crucial IEQ is to every human in every indoor space. The spaces we occupy have a critical effect on our physical and mental health, which in turn affects the quality of the decisions we make, the way we feel, how we move in the world and interact with others, how well we accomplish our daily tasks and work, and in general, the way we experience our lives. And in the United States, where people spend 80-90% of their time indoors, that impact is no small matter.

Over the last few decades, IEQ has emerged as a major area of focus in the architecture, engineering, and construction industry. One main reason for that focus is that it is critical to the U.S. Green Building Council's LEED green building rating system, which considers issues such as volatile organic compounds (VOCs) and other pollutants. Many construction projects aim for green rating systems because they add value to their project, signal a commitment to sustainability and ethical construction and keep designs on the cutting edge. Indoor air quality (IAQ), which used to be the gold standard, is no longer enough. A holistic approach is now considered foundational to building design.

These days, however, building green isn’t the only driver for IEQ. In the past two years, as the pandemic has changed the way we think about spaces, IEQ has really come to the forefront as an important approach for making people feel healthy and safe again. People have reevaluated how and where they want to work and live — and for good reason. In many ways, the events of 2020 have proven to be a challenge for commercial and institutional owners who are sometimes struggling to maintain a quality workforce and managing new pandemic policies that don’t always square with previous building designs. But these challenges have also led to innovations in IEQ design that have brought about exciting new spaces that we never even imagined we needed.

Temperature

The temperature of a space can have a huge impact on the experience of an occupant. In office spaces, thermal comfort can contribute directly to the productivity of workers. In a study at the University of Chicago, worker productivity and absenteeism were evaluated using data from India, the third largest economy in the world. The study showed that productivity drops by as much as 4% per degree when temperatures rise above 80°F. Considering the type of workplace, the culture and location are all part of thinking about thermal comfort. Other research has shown similar impacts in schools. Research shows that high classroom temperatures in schools, as well as low classroom temps, can affect a student's ability to learn and function. In many of these studies, test scores were significantly higher in the classroom where the temperature was 72°.

Acoustics

Poor acoustics can also affect productivity, and as with temperature, it can make occupants feel distracted, irritable or generally uncomfortable in ways that impact their mental and physical health. Acoustics is often discussed in terms of ceiling and wall systems in which the balance between speech intelligibility and speech privacy is important to spaces such as open offices. But noise comfort around HVAC systems is another important aspect of acoustical IEQ. As mentioned before, a hotel where occupants have a hard time sleeping due to noise would not be a sustainable business model. In hospitals where patients need sleep, HVAC noise could have an even more direct impact on occupant health. The size and placement of the system can create problems related to excessive noise if it is functioning poorly or is badly maintained or designed. The rapid flow of air through ventilation ductwork can also transmit noise throughout a building. On the flip side, when a quiet system, the positive acoustics of the building can bring out the best healing and productivity outcomes—giving occupants an experience they want to return to and thrive in.

Quality air

A 2021 study published in Environmental Research Letters journal, showed that poor air quality with high concentrations of fine particulate matter negatively impacts employees' brain function, including response times and ability to focus. The one-year study involved 300 participants ages 18 to 65 working in office in six countries, include the U.S. They were in a variety of industries including engineering, technology, and real estate. Participants employed a custom-designed app on their phones to measure cognitive ability and administer questions. They were given two types of tests: one in which they had to rapidly identify color displays and another that asked basic arithmetic questions. Small levels of PM2.5 and CO2 were introduced to the air, and as concentrations of both pollutants increased, participants completed fewer questions correctly on both tests during the allotted time period, according to the researchers. If color recognition and basic arithmetic are impacted by polluted air, it can be said that a whole variety of cognitive functions could be affected. In hospitals where doctors and nurses must make life-and-death decisions and schools where children need to develop lifelong skills, quality air is the difference between crisis and a society that flourishes on all health and socio-economic levels.

For all these reasons, air conditioning that considers all aspects of clean air flow, temperature control and noise on the highest level can be a major driver, not just for how occupants experience a space for a night in a hotel, but also can shape people’s lives in a profound way.