Keeping a chemical fume hood sash closed mitigates the potential for accidental exposures and reduces institutional energy usage. Fume hoods are one of the most energy-intensive pieces of equipment on campus, with a single hood costing about $2,600 to operate per year. Opened fume hoods can cost upwards of $6,000 per year to operate—the equivalent of 3.5 houses.
While 18 inches is the maximum opening height for a chemical fume hood while performing work, you should always try to keep the sash as low as possible to mitigate exposure to fugitive vapors and splash hazards. Always close the sash when not performing work.
The stickers below are located on the right or left sides of the fume hood, with one piece applied to the sash and the other to the arm. Simply line up the smiley face, and you’ll know your fume hood is safely closed. (The sticker’s smiley face design is based on one shown to effectively decrease instances of fume hood sashes being left open while not in use.)
Note: These stickers are not placed on older fume hoods—including conventional and bypass models—as these units employ constant airflow.