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[Music]
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Narrator: At 7:15 p.m. on February 7, 2008,
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a series of violent sugar dust explosions
devastated the Imperial Sugar Refinery
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in Port Wentworth, Georgia,
just outside Savannah.
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Explosions raced
through the buildings,
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fueled by accumulations of combustible sugar dust
and sugar that had spilled from equipment.
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Thick concrete floors heaved up and brick walls
were blown into stairwells and work areas,
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blocking many exit routes.
Fires spread rapidly.
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[Sound of sirens]
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Narrator: Eight workers died at the scene.
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Six more died later at
a regional burn center.
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Dozens of others were injured.
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The plant's massive sugar
packing buildings were a total loss.
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[Music]
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Bresland: The accident at Imperial Sugar
was the deadliest industrial dust explosion
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in the United States in decades.
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It highlights the extremely serious nature
of combustible dust hazards.
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Vorderbrueggen: There were
significant accumulations of sugar dust
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and spilled granulated sugar on surfaces
throughout this facility.
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Conditions were set for
a catastrophic accident.
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Narrator: Imperial Sugar's sprawling
Port Wentworth complex began operations in 1917
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and grew to become one of the largest sugar
refining and packaging facilities in the U.S.
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Granulated sugar from the refinery
was stored in three 100-foot tall silos
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and then conveyed into packing buildings,
where it was packaged for distribution.
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Granulated sugar was also converted into specialty
products, such as brown sugar and powdered sugar.
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Sugar was transported by a complex system of
bucket elevators, screw conveyors and conveyor belts.
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During this process, sugar spilled
onto floors throughout the work area.
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In places, the spilled sugar
was many inches deep.
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This sugar also contained fine particles,
which became airborne.
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In addition, hammer mills were used to crush the
granulated sugar into powdered sugar, creating even more dust.
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The machines were connected to a dust collection
system, but it was undersized and in disrepair.
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And it was not connected to the
bucket elevators and conveyors.
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Significant amounts of sugar dust
escaped into the work areas.
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Workers routinely used compressed
air to clean packaging machines,
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further dispersing sugar dust
throughout the buildings.
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Over time, large amounts of dust
accumulated on elevated, hard-to-clean surfaces,
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such as ducts, beams
and light fixtures.
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These surfaces were not cleaned often enough
to always keep the dust below hazardous levels.
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In the tunnel beneath the sugar silos, granulated sugar
flowed through chutes onto a long steel conveyor belt.
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From time to time, clumps of sugar
would become stuck in one of the chutes,
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blocking the flow of sugar on the belt, spilling sugar
onto the floor and releasing dust into the tunnel.
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But the tunnel was large and ventilated, so this
airborne dust did not build up to explosive concentrations.
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However, in 2007, the company enclosed the
conveyor belt with stainless steel panels
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to protect the sugar
from possible contamination.
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The enclosure was not equipped
with a dust collection system.
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As a consequence, sugar dust would
now be trapped inside this enclosure.
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On February 7, 2008, clumps of sugar were
found blocking one of the discharge chutes.
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Sugar from the adjacent silo
likely spilled off the moving belt.
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Dust likely accumulated to an
explosive concentration inside the enclosure.
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At about 7:15 p.m., the sugar dust contacted a nearby
ignition source, likely an overheated bearing and exploded.
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[Sound of explosion]
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This primary explosion blew apart the enclosure.
[Sound of explosions]
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And vented into the packing building.
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Accumulated sugar was lofted and ignited by
the advancing fireballs. [Sound of explosion]
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The dust clouds fueled a chain reaction
of secondary explosions ... [Sound of explosions]
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which swept through the buildings.
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Concrete floors buckled, releasing tons of
granulated and powdered sugar into the flames.
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Narrator: Emergency evacuation drills
had not been conducted
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and the explosions had cut the power
to much of the interior lighting.
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In the maze of darkened and
damaged stairwells and passageways,
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workers desperately tried
to flee the growing inferno.
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[Sound of explosion]
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[Music]
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[Sound of sirens and helicopter rotors]
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Narrator: The CSB found that
correspondence dating back to the late 1950s
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showed that plant managers in Port Wentworth
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were aware of the explosive nature of sugar dust
and the danger of dust accumulations.
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As far back as 1961, a memo described a sugar dust
explosion that heavily damaged the powdered sugar mill room.
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Vorderbrueggen: Despite the longstanding
awareness of the explosive nature of sugar dust,
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not enough was done
to manage the hazard.
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Narrator: In 2006, the CSB
issued a study of combustible dust,
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which called on OSHA to establish a
comprehensive combustible dust standard,
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based on the current standards of the
National Fire Protection Association or NFPA.
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In October, 2007, OSHA began
implementing a new National Emphasis Program
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to increase the enforcement of existing
regulations related to combustible dust.
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Vorderbrueggen: Imperial Sugar learned of the
OSHA Combustible Dust National Emphasis Program
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four months before the
devastating explosion at Port Wentworth.
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But management did not act effectively to control
the serious dust problem in the packing buildings.
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Narrator: Less than two
months before the disaster,
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an internal inspection showed that many tons of sugar
were still regularly spilling onto the floors.
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This provided much of the fuel for the
massive secondary explosions and fires.
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[Sound of explosion]
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Narrator: The CSB found that over the years, the Port
Wentworth facility periodically experienced small fires,
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fueled by spilled sugar and
accumulated dust on equipment.
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But none resulted in a sugar dust explosion
that propagated through the plant.
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Narrator: Investigators said that decades
of operating without a catastrophic explosion
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may have lulled managers into complacency.
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In its report, the CSB issued the following
recommendations to the Imperial Sugar Company.
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Apply NFPA standards to the design and operation
of the rebuilt Port Wentworth facility.
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Develop and implement comprehensive combustible
dust control, housekeeping and training programs.
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Improve emergency
evacuation policies and procedures.
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Bresland: Companies can go a long way to
control combustible dust within their own facilities
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by following the existing recommendations
of the National Fire Protection Association.
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But it is also time for a
comprehensive federal standard on combustible dust.
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Narrator: In April, 2009, OSHA announced plans
to begin rulemaking on a
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combustible dust standard
for general industry.
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In its final report on
the Imperial Sugar accident,
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the CSB recommended that OSHA move
forward expeditiously with the new standard.
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Bresland: Without regulation,
enforcement and education,
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workers will continue to be at risk
from catastrophic dust explosions.
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Narrator: For further information,
please visit CSB.gov.
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[Music]
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