Thomas Alva Edison.
Thomas Alva Edison.

The phonograph.  The lightbulb.  The motion picture camera.  The alkaline battery.

The fume hood?

As you’ve probably already guessed, the first four items you see above were invented by the legendary Thomas Alva Edison.  But the fume hood? Well, not quite.

Edison was one of the first scientists on record to be concerned about lab safety and ventilation, however.  According to a recent article in Lab Manager Magazine:

“Edison used the fireplace chimney in his lab to exhaust noxious fumes and odors from his experiments into heated rubber compounds, using the natural draft of the chimney to expel the gases.”

Labconco, one of the major manufacturers of fume hoods, launched its first commercial model in 1936.  The modern fume hood has since undergone many changes, including the introduction of the HEPA filter in the 1940s, and the development of the variable air volume hood (VAV); they are now ubiquitous and play an extremely important role in laboratory safety around the world.

They are also energy hogs.

Uh oh, asbestos...
Uh oh, asbestos…

Take a moment to recall when you left home for work this morning.  Only this time, imagine you’ve left your AC or central heating running full blast.  You’ve also opened all your windows and set up fans around the house to blow all that hot or cold air outside.  Now imagine keeping this up 24/7.  That’s a lot of energy use.

According to a report prepared by Silas Hilliard for Caltech in 2008, fume hoods use up to four times the energy of a typical house and account for $4.2B dollars in energy use worldwide.  Over the course of his research, Hilliard found that VAV hoods were rarely used properly – the average fume hood at Caltech accrued energy costs of $4718 per year, and was only closed nine percent of the time.

He found that by increasing awareness, fume hoods could remain closed three-quarters of the time, resulting in a savings of $3,412 per hood a year.

The lesson is simple.  By keeping the sash—the name for the lid of the fume hood–closed as much of the time as possible, significant energy savings can be attained. 


Shut The Sash – Harvard Green Labs

In 2005, Harvard’s Chemistry and Chemical Biology department came up with a novel way to promote energy savings in its labs:  the Shut The Sash competition.

What began as a pilot program in five labs has now expanded to 19 laboratories and over 350 researchers.  The program taps into Harvard researchers’ competitive spirit and inspires behavior change, and to date saves more energy than any other behavioral program at the university.

sashHow it works:

Each month, goals are set for individual labs in terms of exhaust airflow averages – each lab is assigned a customized goal based on the number of hoods, usage patterns and airflow ranges, enabling comparisons between labs with different research habits and lab setups.

Readings are taken of exhaust airflow for each lab every 30 minutes through the building automation system, with performance tracked on a daily, weekly and monthly basis.  All labs that meet their goals are entered into a monthly pizza party raffle, with wine and cheese celebrations held twice a year to reward labs that consistently meet their goals.

Among the tools used in the contest are reminder magnets on each sash, as well as signs at laboratory exits.  Emails are sent out twice a month – the first in the middle of the month to let the labs know if they are on track to meet their goals, and the second just after the end of the month to announce the winners.

Posters with up-to-date results are also made available to all labs and displayed prominently on their bulletin boards.  Finally, a volunteer in each lab is recruited by the professors to stay on top of fume hood use and remind others of the importance of keeping the sash closed.

Take a moment to watch the video below for more information:

The program’s energy-saving impact has been significant.  As of 2010, fume hood exhaust levels have been reduced by 30% compared to pre-contest levels, resulting in over $180,000 in annual energy savings and preventing nearly 1.2 million pounds of greenhouse gas emissions – the equivalent of permanently removing roughly 120 cars from the road, according to the Green Harvard website.

As global warming becomes an increasing threat to our survival, green initiatives are imperative.  “Going green” is a step-by-step process.  If you work in a lab and are interested in learning more about sustainable lab practices, the Labs for the 21st Century program, co-sponsored by the U.S. Environmental Protection Agency and the U.S. Department of Energy, is an excellent source.  They have prepared a series of Best Practice Guides to provide information on the design, construction and operation of specific technologies that contribute to sustainability and energy efficiency in the lab.

Click here to view the guides. 

Click here to download the guide for fume hoods.

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