Laboratory ventilated sink use for glassware cleaning: Design, installation, and evaluation

Numerous methods for cleaning laboratory glassware are currently available. Existing analytical method constraints at Roche Colorado Corporation (RCC), a Responsible Care company, limit the use of dishwashers and other automated glassware cleaning systems. Therefore, solvent-based laboratory glassware cleaning is performed to remove interfering residues, and represents an area of potential occupational exposure to chemicals. Typical cleaning steps include an initial solvent wash, soap and water cleansing, and a final solvent rinse to dry the glassware. Acetone, a common solvent used for this purpose, has an American Conference of Governmental Industrial Hygienist (ACGIH) TLV-TWA (8 hr) of 500 ppm and TLV-STEL (15 min) of 750 ppm. Exposure monitoring during glassware cleaning indicated that airborne concentrations of acetone may exceed these occupational exposure limits (OELs). To address the potential exposure to acetone vapors, engineering controls, consisting of a custom countertop slotted sink hood and an in-sink downdraft system, have been designed and implemented. Field validation indicated that both ventilated sinks were effective at controlling airborne acetone concentrations well below acetone's OELs.