P3-31 Cleanliness of Environmental Surfaces in Elementary Schools as Determined by ATP Levels

Wednesday, August 3, 2016
America's Center - St. Louis
Ana Romero, Clemson University, Clemson, SC
Morgan Chao, Clemson University, Clemson, SC
Cortney Leone, Clemson University, Clemson, SC
Lalani Jayasekara, Clemson University, Clemson, SC
Angela Fraser, Clemson University, Clemson, SC
Introduction: Environmental surfaces in U.S. schools are vehicles in the transmission of microorganisms known to cause acute gastroenteritis.  Students who contact contaminated surfaces then eat without washing their hands increase their risk for illness.  

Purpose: Our aim was to determine the cleanliness of environmental surfaces in elementary schools as determined by ATP levels.

Methods: In Spring 2015, trained data collectors swabbed surfaces of 19 objects in cafeterias (27 observations), bathrooms (100 observations), and 3rd grade classrooms (192 observations) at five elementary schools in South Carolina for ATP revelation—expressed as relative light units (RLU)—using a close zig-zag pattern (AccuPoint Advanced ATP Hygiene Monitoring System, Neogen, Lansing, MI).  In cafeterias, surfaces were swabbed before lunch; in bathrooms and classrooms, surfaces were swabbed after lunch.  ATP levels on each surface were categorized as “Pass” (≤150 RLU), “Caution” (151-299 RLU), or “Fail” (≥300 RLU).

Results: The objects that failed most frequently in cafeterias were eating table tops (n=5; 5 failed), PIN machines (n=4; 4 failed), and hand sanitizer pump handles (n=3; 3 failed); in bathrooms were sink faucet handles (n=22; 3 passed, 19 failed); and in classrooms were computer keyboards (n=29; 2 passed, 1 caution, 26 failed).  The objects that passed most frequently (or at all) in cafeterias were chair seats (n=5; 1 passed, 4 failed), tray rails (n=5; 1 passed, 4 failed), and milk refrigerator door handles (n=5; 1 passed, 4 failed); in bathrooms were drying devices (n=22; 5 passed, 2 caution, 15 failed); and in classrooms were backpack/coat storage areas (n=24; 11 passed, 2 caution, 11 failed). 

Significance: We determined that many surfaces in our sample of five elementary schools were unclean.  These findings can inform cleaning and disinfection protocols of high-risk surfaces as well as can demonstrate the importance of good hand hygiene practices among students and staff.