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Invention Awards: An Escape Harness for
Skyscrapers
By Elizabeth Svoboda,
May 14, 2009
Popular Science
Invention: Rescue Reel
Inventor: Kevin Stone
Cost: $335,000
Time: 6 years
Is It Ready Yet? 1 2 3 4 5
As the 9/11 inferno
unfolded on television, one question kept
dogging Kevin Stone: Why weren't the people
trapped in the World Trade Center able to
make their way to safety? "I said to myself,
This is crazy," recalls Stone, an orthopedic
surgeon and seasoned inventor in San
Francisco. "There should be a better way to
exit a skyscraper when something like this
happens."
Stone found all the
existing systems for rescuing people from
high places to be flawed or impractical, so
he designed a device based on a fishing
reel, a simple harness that would lower
people steadily from skyscraper heights on a
secure length of cord. The Rescue Reel
affords people an easy way to engineer their
own escape: All users have to do is open a
file-drawer-size container and hook a Kevlar
cord to a secure object or connection point
(such as between a door and its frame). Then
they step directly into the
one-size-fits-all harness and rappel through
an open window up to 100 stories from the
ground. No special training is needed, and
the entire sequence could take less than a
minute.
Stone's major innovation is a centrifugal
braking system that automatically controls
the rate of descent. The Rescue Reel's cord
unwinds from a spool and wraps around a
shaft connected to a brake. As the shaft
spins, a set of brake pads exerts force on
the inner edge of the brake housing,
smoothly slowing the user down. Should the
automatic brake fail, the device is also
equipped with a manual backup brake lever.
Descending from 100 stories up takes less
than four minutes—about two seconds per
story.
Stone tested a prototype in 2007, and Skala,
a company specializing in rope-access
systems, has since conducted extensive tests
of the device at California's Vallejo Fire
Department. It's a significant upgrade from
the slow, cumbersome rope systems
firefighters usually use for high-floor
rescues, says fire-safety consultant Scott
Douglass. "It's a lot more automated, and
it's easier and more intuitive for the
trapped person to use." He thinks it could
be used for cliff rescues as well.
Now that testing is complete, Stone is
preparing to market the Rescue Reel. A
commercial-ready version should be available
next year for about $1,500. He foresees
lowering the price considerably once he
starts mass production, making it practical
for building owners who want to give their
tenants an escape clause.
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