High-proof (e.g. 70%) ethanol can be an effective sanitizing agent against the coronavirus causing COVID-19. Spraying of small winery surfaces or equipment for sanitization with this solution is not problematic, especially in a well-ventilated area. However, pumping high proof ethanol (for the purpose of creating sanitizing solution or sanitizing large pieces of equipment) using a normal winery pump could be hugely dangerous (explosion hazard) and should be avoided.
While winery and distillery pumps are extremely similar, there are critical operational and safety distinctions between the two. High proof ethanol has a flash point of 12~16°C (53°F to 61°F), depending on the concentration, and as such is hazardous at below-room temperature. Distilleries are typically rated by the National Fire Protective Agency as Class 1 Division 1; and spirits blending/bottling plants are typically Class 1 Division 2. As such, all liquid handling equipment, especially pumps, sensors, and valves are typically "intrinsically safe" and explosion proof, where the electrical portions of the equipment are sealed away from access to any combustible gasses (i.e. ethanol). Winery pumps are almost never intrinsically safe/explosion proof, as normal wine is not a combustion hazard. As such, there is a substantial hazard present in using winery process piping and pumps for high proof ethanol movements. Any such movements of high-proof ethanol should only be made using appropriately rated pumps in facilities designed for this type of work.
Dr. David E. Block
Ernest Gallo Endowed Chair in Viticulture and Enology
Professor, Department of Viticulture and Enology
University of California, Davis
Dr. Konrad V. Miller, P.E.
Lecturer, Department of Viticulture and Enology
University of California, Davis