[Music] Narrator: November 22, 2016. The ExxonMobil Refinery in Baton Rouge, Louisiana. A fire erupted during maintenance activities,
severely burning four workers. The fire occurred when operators
inadvertently removed bolts that secured a piece of pressure-containing equipment
to a type of valve known as a plug valve. When the operators then attempted to open the valve,
it came apart and released flammable isobutane, which formed a vapor cloud that quickly ignited. [Sound of explosion] Sutherland: During our investigation, the CSB learned
that the operators attempting to open the plug valve were following accepted practices within the refinery. Unfortunately, those practices lacked a safety hazard
analysis, which needlessly put the workers at greater risk. The management of safety is critical to the
protection of workers and the integrity of facility operations. [Music] Narrator: The fire at ExxonMobil's Baton Rouge refinery
occurred in the sulfuric acid alkylation unit. There, isobutane and olefins are
converted into a major component of gasoline, through a reaction involving sulfuric acid. On the day of the incident, two operators were
preparing to put a spare isobutane pump into service. To do so, the operators needed
to open the pumps' inlet valve. That plug valve was operated manually. A hand wheel and a piece of equipment called a gear box
were connected to the valve by a support bracket. The gear box uses gears to make it easier to turn
the valve stem into the open or closed position. The operators turned the hand wheel
on the spare pump's inlet plug valve. But the gear box was not working properly
and the valve would not open. When the gear box was malfunctioning, it was an accepted practice in the alkylation unit
for operators to remove the gear box, so that a pipe wrench could be used to
turned the valve stem and open the valve. The gear box was connected to the valve body
by the support bracket using bolts. The operators removed four vertical bolts from the valve. But unknown to the operators, these bolts also secured a critical pressure-containing
component of the valve known as the top cap. Approximately three percent of the numerous
plug valves in the refinery's alkylation unit were designed so that the gear box
support bracket attached to the top cap. With this 30-plus year-old design, removal of the gear
box support bracket can have catastrophic consequences. Approximately 97 percent of the valves
were newer models with updated design that did not connect the gear box support bracket
to pressure-containing equipment, making it less likely to remove the incorrect bolts. With bolts removed from the top cap, one of the operators attempted to open the valve
by rotating the valve stem with a pipe wrench, while the second operator stood by and observed. The valve immediately failed and came apart. Pressurized isobutane escaped from the valve,
forming a flammable white vapor cloud. The two operators warned others in the area
and directed them to evacuate. Approximately 2,000 pounds of isobutane
released to the atmosphere. The vapor cloud likely found an energized welding machine, roughly 70 feet away from the initial release and ignited. [Sound of explosion] Narrator: The resulting fire seriously injured one
ExxonMobil employee and three contractors working in the area. Wingard: Our investigation into the incident revealed
that management at the ExxonMobil Baton Rouge refinery were accepting of operators in the alkylation unit
removing malfunctioning plug valve gear boxes without adequate written procedures or training. Narrator: The CSB also found that although refinery
operators did receive training on hard-to-operate valves, that training did not specifically address how to remove
an inoperable gear box from the older plug valve model. Wingard: In our Safety Bulletin, we outlined
three key lessons learned from this incident. Narrator: The first key lesson is to
establish detailed and accurate written procedures for working performing potentially hazardous work. This is especially important
when different types of equipment or configurations exist that could cause confusion. A second key lesson is to provide training to ensure
that workers can perform all anticipated job tasks. Training should include a focus on
processes and equipment to improve hazard awareness and help prevent chemical incidents. Wingard: In our Safety Bulletin, we
emphasize the hierarchy of controls. This is a method of evaluating safeguards
to provide effective risk reduction. Within the hierarchy of controls, an
engineering control, such as improved valve design, is more effective than a lower-level administrative control, such as a sign warning workers that the gear box
support bracket connects to pressure-containing components. Narrator: The CSB found that the
30-plus year-old valves left in the refinery were not explicitly required to
be updated to the safer design. That is because the older design did
technically adhere to current industry standards, which call for items like gear boxes to be capable of
removal without affecting pressure-containing parts. That could be accomplished by removing two horizontal bolts that connect the support bracket directly to the gear box, rather than the four vertical bolts that
secure the support bracket to the top cap. But on the day of the incident, the operator did
not remove the two horizontal bolts. [Hissing sound] Wingard: The American Petroleum Institute,
an industry trade association, says in its safety guidance for improving human
performance to make it easy for people to do things right and hard for them to do things wrong. Updating all of the older valves to the safer valve design, as was done to approximately 97 percent
of the valves in the alkylation unit, could have ultimately prevented this incident. [Hissing sound] Narrator: A third key lesson from the CSB's Safety Bulletin is to apply the hierarchy of controls
to mitigate identified hazards. The CSB also found that in its most
recent alkylation unit process hazard analysis, the refinery did not evaluate the human factors
associated with valve operation and maintenance. Wingard: Had the refinery adequately addressed human
factors in its most recent process hazard analysis, workers could have discussed difficulties
with removal of the plug valve gear boxes, prompting the company to identify potential hazards. As a result, the older valves could
have been recommended for replacement and the incident would have been avoided. [Sound of explosion] Sutherland: The safety management practices
outlined in our Bulletin could have prevented the fire in Baton Rouge. We urge companies to share and implement
our key safety lessons at their facilities, in order to prevent future injuries and property damage. Thank you for watching this CSB Safety Video. Narrator: For more information, please visit CSB.gov. [Music]
