Boston Children's Hospital Fume Hood Hibernation Demonstrates Safety and Savings

Fume hood hibernation is the practice of temporarily disabling a fume hood from active use, while still maintaining the equipment so it can be returned to service when needed. Labs hibernate hoods during research transitions, construction renovations, or times when the space is not in use. With variable air volume (VAV), hibernation presents a cost-saving alternative that reduces energy due to reducing airflow and demands on the HVAC system. Hibernating fume hoods can also reduce a lab’s carbon footprint. As part of their strategy during I2SL’s 2024 Shut the Sash pilot competition, participants at Boston Children’s Hospital were able to identify a number of fume hoods to hibernate through usage audits, an effort that contributed to the team's success in winning the competition.

Chuck Blanchette, green labs program lead for Boston  Children’s Hospital, recently spoke during I2SL’s Education Week about how the hospital launched its fume hood hibernation efforts during the Shut the Sash pilot. The hospital has over 200 fume hoods; to identify hoods that were underutilized, Chuck started lab walk-throughs during the pilot. Every department and research group has different needs, and the walk-throughs started conversations with principal investigators and researchers, while the pilot helped them understand their fume hood usage. In total, they identified 28 underutilized hoods; in some cases, fume hoods could be shared among several labs, while they determined that eight hoods could be hibernated. Two of those hoods were constant volume, which meant they didn’t necessarily save energy when shut off; Chuck estimated that hibernating six VAV fume hoods has saved the hospital $16,000 in energy costs.

To safely hibernate the hoods, Chuck enlisted the help of the hospital’s environmental health and safety (EHS) staff and facilities department to properly shut off the air supply, vacuums, venturi valves, gas, and electricity to the hoods. During hibernation, signs on the hoods alert researchers that they are no longer in service, sashes are kept shut at all times, and periodic checks are conducted to ensure safety and readiness. Chuck noted that they do not go through this shut-off process unless the fume hood can be hibernated for a month or more, and they only decommission a fume hood if it is going to be permanently shut off, as the process of capping vents, sealing ductwork, and removing equipment can be costly. Before restarting a hibernated hood, Chuck said, filters are replaced and contractors conduct testing to recertify the hoods before they can be used again.

Learn more about the award-winning Shut the Sash competition and fume hood hibernation effort at Boston Children’s Hospital, as well as how the hospital’s green labs program has enhanced researchers’ sustainability efforts, by accessing Chuck’s Education Week presentation recording here.