I-Corps: Air purification technology using germicidal ultraviolet radiation

The broader impact/commercial potential of this I-Corps project is to bring the public health benefits of hospital grade air purification to a broad customer base, from personal protective equipment (PPE) to room air disinfection. The COVID-19 pandemic has increased awareness and demand for airborne pathogen purification which will likely continue long-term. Currently available solutions, from fitted N-95 masks to powered air purifying respirators (PAPRs) are often either too cumbersome, too restricting, too uncomfortable, or too expensive for widespread use. The proposed technology could be used as a module to enhance or to be an alternative to pre-existing PAPRs for industrial markets. Applications requiring high-level air purification have often required cost prohibitive, customized, upper room ultraviolet (UV) germicidal irradiation (UR-UVGI) systems. The proposed technology provides an economical, standard, plug-and-play solution with comparable germicidal efficacy, making hospital-grade air purification practically achievable for a host of public spaces such as schools, offices, restaurants, and transportation hubs.

This I-Corps project will further develop an ultraviolet (UV) based air disinfection technology which amplifies UV-C radiation to germicidal levels capable of purifying flowing air. The UV-C is generated using light emitting diode (LED) sources to prevent harmful by-products, while providing radiation doses that maximize damage to pathogen nucleic acids. The current level of air disinfection is governed not only by the incident radiation but by the residence time distribution of air in the irradiated zone. Inhomogeneities in radiation or airflow cause a significant bottleneck in disinfection efficiency. Further, the radiation incident on the flowing air needs to be sufficient, given the power limitations of UV-C LEDs. The proposed project uses a number of cavities, with particular geometrical and reflective properties, to provide amplified, uniform incident radiation and mixing conditions to allow for integrated and serial disinfection, ameliorating current issues. A collection of disinfecting cavities can be configured to accommodate the required level of air disinfection or the clean air delivery rate.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.