Abstract
The development and validation of the Biosafety Level 2 (BSL-2) enhanced containment system located at the produce pilot plant facility of the U.S. Department of Agriculture—Eastern Regional Research Center is presented here. This multi-purpose containment is used to enclose pilot and pilot scale washing and sanitizing equipment for fruits and vegetables, or other decontamination equipment where aerosol generation is likely, and complete protection is required for researchers. This containment is operated under a negative pressure with all exhausted air (approximately eight containment air exchanges per hour) being passed in parallel through two hydrophobic HEPA filters. During operation, personnel are excluded from the containment, materials are introduced into and removed from the containment via pass-throughs, and equipment is operated via computer control and glove ports.
At the completion of any series of processing trials, vegetative bacterial cells
remaining within the containment, and in the processing water, are inactivated by raising
the internal temperature of the containment, and all contents, including equipment,
processing water and waste water to sufficiently inactivate all bacterial cells, except
spore formers, using industrial steam at atmospheric pressure. We have demonstrated the
feasibility and safety of conducting multiple trials using pathogenic bacteria with pilot
scale processing equipment within the containment, and then inactivating surviving
vegetative bacterial cells with the steam-in-place process. Furthermore, we validated
pilot-scale surface pasteurization processing equipment capable of significantly reducing
cell densities (in excess of 5 logs) of