Comparative analysis of ventilation efficiency on ultrafine particle removal in university MakerSpaces

Lynn E Secondo; Hayat I Adawi; John Cuddehe; Kenneth Hopson; Allison Schumacher; Larry Mendoza; Charles Cartin; Nastassja A Lewinski

doi:10.1016/j.atmosenv.2020.117321

Comparative analysis of ventilation efficiency on ultrafine particle removal in university MakerSpaces

Atmos Environ (1994). 2020 Mar 1:224:117321. doi: 10.1016/j.atmosenv.2020.117321. Epub 2020 Feb 6.

Authors

Lynn E Secondo¹, Hayat I Adawi¹, John Cuddehe², Kenneth Hopson³, Allison Schumacher⁴, Larry Mendoza⁵, Charles Cartin⁶, Nastassja A Lewinski¹

Affiliations

¹ Department of Chemical and Life Science Engineering, Virginia Commonwealth University, 601 W. Main St, Richmond, VA, 23284, United States.
² Department of Chemistry, Virginia Commonwealth University, 1001 W. Main St, Richmond, VA, 23284, United States.
³ James Branch Cabell Library, Virginia Commonwealth University, 901 Park Ave, Richmond, VA, 23284, United States.
⁴ da Vinci Center, Virginia Commonwealth University, 807 S Cathedral Pl, Richmond, VA, 23284, United States.
⁵ Environmental Health and Safety, Safety and Risk Management, Virginia Commonwealth University, 1008 East Clay Street Box 980112, Richmond Va, 23298, United States.
⁶ Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, 401 W. Main St, Richmond, VA, 23284, United States.

Abstract

The proliferation of 3D printing MakerSpaces in university settings has led to an increased risk of student and technician exposure to ultrafine particles. New MakerSpaces do not have standardized specifications to aid in the design of the space; therefore, a need exists to characterize the impacts of different engineering controls on MakerSpace air quality. This study compares three university MakerSpaces: a library MakerSpace operating ≤4 devices under typical office space ventilation with no engineering controls, a laboratory MakerSpace operating 29 printers inside grated cabinets, with laboratory-grade ventilation, and a center MakerSpace operating ≤4 devices with neither engineering controls nor internal ventilation. All MakerSpaces were studied under both controlled (using a standard print design) and uncontrolled (real-time user operation) conditions measuring emitted particle concentrations in the near-field. Additionally, volatile organic emissions and the difference between near-field and far-field particle concentrations were investigated in multiple MakerSpaces. The center MakerSpace had the greatest net increase in mean particle number concentration (+1378.9% relative to background during a print campaign using polylactic acid (PLA) filament in a MakerBot (MakerBot-PLA)). The number-weighted mean diameter had the greatest change relative to background during the library campaign, +37.1% for the Lulzbot-PLA and -56.1% for the Ultimaker-PLA studies. For the standard NIST design with MakerBot-PLA, the laboratory's particle removal ratio was 30 times greater than in the library with open cabinets and 54 times greater when the cabinet doors were closed. The average particle removal rate from the center MakerSpace was up to 2.5 times less efficient than that of the library for the same MakerBot-PLA combination. These results suggest ventilation as a key priority in the design of a new university MakerSpace.

Keywords: Air pollution; Buildings; Environmental health; Indoor air quality; Nanoparticles; Ventilation.

Grants and funding

T32 ES019854/ES/NIEHS NIH HHS/United States