Purifier Vertical Clean Benches are available for tissue culture and media plate preparation under ISO Class 5 conditions to prevent airborne contamination. It does not provide user protection so should not be used in conjunction with biohazardous material, toxins or radionuclides. During operation, room air is drawn through a prefilter in the top of the cabinet to trap large particles. Air flows through a 99.99% efficient HEPA filter and is projected vertically over the work area. This HEPA-filtered air prevents contaminants from entering the work area and provides a particulate-free work environment that minimizes cross contamination. Indicator lights monitor differential pressure across the HEPA-filter. The front sash and side panels are made of scratch-resistant tempered safety glass. Glare-free, fluorescent lighting is located outside the contaminated work area, and light and blower switches are located on the front of the cabinet within easy reach of the operator.