Recorded at AIHce EXP 2021
COVID-19 risk reduction guidances recognize the importance of engineering controls. AIHA Back to Work Safety Guidance documents provide a relative risk reduction paradigm which compares risk reduction through engineering controls (ACH) to the use of face coverings and N95 respirators. A mathematical model to estimate relative risk reduction is found in the CDC Guidelines for Environmental Infection Control in Health-Care Facilities. To validate the model through collection of empirical data, a simulated elementary school classroom environment was constructed. This study design included; a) room ventilation provided through a floor-mounted unit ventilator; b) a nonpathogenic surrogate (SuranovÂ®) with UV-fluorescent dye was dosed onto room surfaces; c) an aerosol generator was used to dose the room air; d) prescribed human activities were performed; e) airborne particle concentrations were measured using real-time instrumentation; f) cleaning was performed following the AIHA BTWS Guidance; g) surface cleanliness was assessed by real-time ATP analysis; and g) a black light was used visualize surface cleanliness and high contact areas. This session will discuss the findings and conclusions of this study.
Upon completion of the session, the participant will be able to:
- Describe how removal rates relate to ventilation air changes.
- Compare the goodness-of-fit between empirical data and the CDC formula.
- Recognize real-time ATP testing as an indicator of cleaning efficacy.
Ben Heckman, MPH, CIH
Mr. Jacob Persky, MPH, CIH
Fred Boelter, CIH, PE, BCEE, FAIHA
Frank Pagone, Ph.D.