According to the U.S. Environmental Protection Agency (EPA), the air we breathe inside can be two to five times more polluted than the air outside, ranking indoor air pollutants among the top five environmental risks to public health. The impact of air pollutants can range from subtle, such as eye irritation, headaches, nausea and fatigue to severe, increasing the risk of asthma, pulmonary infections, allergies and even some forms of cancer.
In the workplace, poor indoor air--which is often exacerbated by volatile organic compounds (VOCs) released by flooring, furniture, cabinetry, cleaning products and electronics – hinders comfort, attention span and productivity, costing employers an estimated $15 billion annually due to lost productivity and sick leave. Thankfully, the development of lower-emitting products that support healthier indoor air quality (IAQ) is on the rise.
Low-emitting products are a critical piece of the IAQ improvement puzzle, but smart building designs and new sensor technologies are enabling architects and building owners to help deliver the levels of improved IAQ necessary to positively impact the health of building occupants.
“Building sensors play a critical role in realizing the promise of this new frontier in health and environmental building performance,” says Dr. Elliott Horner, a lead scientist with UL Environment’s team.
Building sensors are designed to monitor air quality levels inside buildings for everything from VOCs to dust to formaldehyde and more. Sensors provide a real-time view into whether the quality of the air in circulation has fallen below target levels. In some cases, the sensors execute control measures to adjust the quality of air flow.
No wonder then that the global market for sensors is slated to reach $3.2 billion by 2025. But just how effective are they in delivering on their promise?
“The concern is in not knowing how reliable the sensor’s reading outputs are,” adds Horner. “You can have a wonderfully designed system to display all sorts of information and integrate different building equipment, but if the sensor readings are not of sufficient quality, then the outcomes are not going to be any better.”
In its Marietta, Ga. based lab, UL helps sensor technology manufacturers understand the reliability of their products by putting them through rigorous evaluations. To test the products, UL utilizes a dynamic environmental chamber that allows for a tightly controlled environment containing well-mixed air at specified pollutant levels while preventing interference from the air outside the chamber. Multiple sensors are placed in the chamber and pollutants at various levels are introduced to establish the range of reading sensitivities. Pollutant levels are also monitored with research grade instruments to benchmark the sensor performance.
Based on the International Organization for Standardization (ISO) 16000-29 Standard, UL teams evaluate the performance of the VOC detectors against measures of response time, stability and range. Other tests include considering how humidity, barometric pressure and the speed of air movement might affect their ability to function properly.
UL’s environmental testing chambers were designed and built originally for product emissions testing, but the same testing principles are leveraged for sensors.
“We have technology that was developed to see what’s coming off materials, but we can also put sensors in the chamber,” Horner explains. “In the very same way that we can validate product emissions within the chamber, we can expose the sensors to specific levels of pollutants and see how close they come to accurate readings.”
“With the rapid adoption and integration of sensors, monitors and dashboards within building systems, building occupants will become increasingly sensitized to the ways in which their buildings are managing natural resources and providing people clean and healthy air to breathe,” continued Horner. “Testing sensors to help ensure confidence in their performance is a necessary first step – one that can help manufacturers, building owners and tenants feel confident that their indoor air quality management programs are creating healthier indoor environments.”