Frank Bird Accident Pyramid

Assignment Name
Assignment Code
Student Name
18 Feb 2020
Pipe assembly blows off, strikes operator
A. Frank Bird's Domino theory
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According to Frank Bird's Domino theory, the circumstance that leads to injury or
loss of life is dependent on five dominoes; lack of control (management), basic causes
(origins), immediate causes (symptoms, incident (contacts), and people property (loss)
(1). Considering the incident of pipe assembly blow off, the five Dominoes are
illustrated in detail:
Loss- The incident has led to severe physical harm as well as property damage in the
location of the incident that is well site north of Fort St. John, British Columbia (1).
The incident has led to death, serious and disabling injury to the employees working
near to the pipe assembly. Some people have minor and internal injuries. There has
been major property damage as well. The CO2 operator has experienced major fatal
injuries as the pipe assembly became uncontrollable under high pressure and banged
him.
Contact- contact is the incident or accident which is caused by unsafe conditions. In a
well-stimulated site, a mobile tanker is parked between two other mobile tankers,
which of these streets the direct release of excess carbon dioxide to the sideways.
Hence, the CO2 operator designs a pipe assembly for redirecting the venting gas in
the front of the mobile tanker, with the use of piping components. When the operator
released the excess carbon dioxide through the discharge valve, the pressure of
venting gas was so high that it unthreaded the pipe assembly and moved in an anti-
clockwise direction, and eventually created huge destruction.
Immediate causes- According to the report by WorkSafeBC engineering (2), the
immediate causes identified for the incident is the disconnection of the pipe during the
gas was venting. Further, it is expected that a torque of 2200 foot-pounds has helped
in unthreading the pipe. Another immediate cause concluded in the engineering report
is the compressed gas which escaped from the pipe elbow at 45 degree, thereby
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creating a trust which eventually made the pipe rotation and unthreading in the anti-
clockwise direction. It is also believed that the white substance present in the pipe
thread has acted as a lubricant and assisted in unthreading in lower torque.
Basic causes- The basic cause which led to the accident is inadequate safe working
practices. According to the work procedure mention in the WorkSafeBC, at a distance
of 300 ft from the direction of the discharge valve facing, there should be nothing2.
The mobile tankers were also placed side by side with minimal gap between them.
The site supervisor had not provided adequate supervision which forced the
employees to work by themselves with minimum knowledge.
Lack of control by management- There was a lack of supervision and proper work
practices. The employer had not followed the Occupational Health and Safety
Regulation and the Workers Compensation Act (2).
B. Petersen’s motivation and reward satisfaction model
Motivation - The job command designed by the employers of the company revealed
the lack of concern related to the effective monitoring of employees’ safety standards.
On the basis of the case study, a laissez-faire style of leadership is in upper
management. Due to the lack of effective supervision, the side workers have to work
and direct by themselves with limited knowledge related to work procedures. It is
further identified that the extra employees when involved in the transportation of pipe
in between the tanker unit. This reveals the lack of safety culture and evidence with
working standards there does not exist any peer pressure for the site supervisor which
restricted him from inquiring about safe working standards (3).
Ability- It is identified that the site workers are inexperienced and lack sufficient
capacity to complete the standard work procedure. the workers are not provided with
any additional training or on-site supervision which increases the risk of an accident.
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C. Peterson's second accident causation model
Human arrows
Decision for error:
 Minimum consideration for the event failure
 Employees assumed that an improved solution would provide a successful
result.
Traps:
 Improper storage of mobile tankers, without any proper layout for placement
between two or more mobile tankers.
Overload:
 Lack of documented safe work practices resulted in situational factors.
 Lack of direct instruction from managerial staff or supervisor.
 Presence of environmental factors like increased noise level
System failures
 There was no alternate procedure for safe working practices, particularly while
placing the mobile tankers.
 Lack of supervision and monitoring.
 Lack of worker's responsibility to ensure peer safety in the workplace.
 Workers are unable to recognize the hazard or risk related to venting of the
tank with a non-engineered tool.
D. James Reason Model
Energy
The pressure generated from the release of CO2 eventually generated thrust which led
to the unthreaded of the pipe. This incident resulted in the fatal injury of the worker.
Flawed Defences
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Firstly, there should be program elements to increase awareness related to safe
working procedures. Secondly, the organization management team should ensure
regular inspection and supervision of the worksite (4).
Inappropriate occupational health and safety management system
There was no safe procedure for placing the mobile tankers side by side along with
lack of supervision leading to a fatal situation.
E. 5 whys model
This model is a technique to gain a logical conclusion by asking "why?" in five
different questions (4).
Some of the potential five whys question for this particular case scenario is as follows
 Why did the vent pipe fail in that situation?
The vent pipe failed as it was not an engineered vent, rather it was designed by
the worker himself by using the immediately available parts on the worksite.
 Why was such a vent pipe necessary? (5)
It was necessary for the venting of four mobile tankers aligned by upside by
side.
 Why was the worker brinks truck due to the unthreading vent pipe?
The release of 300 lb of pressure from the mobile tanker generated enough
torque which eventually resulted in the unthreading of the vent
(WorkSafeBC).
 Why was the working site set up in such a manner?
It was set up in accordance with the operator's manual without any mention of
conflict resolution.
 Why was there negligence in supervision and monitoring on the worksite?
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The supervisor did not provide attention to the safe work practices and was
unaware of any requirement related to the venting queen (6).
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Garbage truck hits pedestrian overpass
A. Casual factors
In this incident, the driver of the garbage truck was heading on to collect the last
garbage of his shift. He was unaware that the garbage box has become slightly
elevated while traveling on the highway (7). The elevated garbage box hit one side of
the pedestrian overpass. The pedestrian overpass has one support pillar as a floating
end while the other support pillar is designed as fixed and. When the garbage box hit
the floating end support of the pedestrian overpass, it suddenly fell down on the truck,
leading the driver fatally crushed (8).
Causal factors
People: The elevation of the garbage box was due to an unintentional error on the part
of the diver. The diver unintentionally placed the TIP switch which eventually raised
the garbage box. However, he was supposed to press to open the top door. An
unintentional error has occurred due to a lack of standardization between the human
command and machine. The driver drives approximately 3 to 4 different types of
vehicles per week which have similar types of control panels. However, this truck was
different from the usual trucks which were being used by the driver. The truck
involved in the incident has a TIP switch. It is believed that the driver might be
looking for the "top door" switch that accidentally activated the TIP switch because of
the inconsistencies in the control panel. This factor is considered to be significant
rather than influencing. It is because it acts as a major cause for hitting incident of the
garbage truck on the pedestrian overpass (9).
Environment: There were no environmental-related factors that are responsible for
this incident. This factor is neither considered as significant nor influencing.
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Equipment: The absence of ANSI standards in the form of audible or visual alarm
forwarding the driver about the elevated garbage box is another cause for the
incident. This factor is considered as influencing, because it seduced the hitting
incident of the garbage truck on the pedestrian overpass (11).
Management: The management factor is the non-routine and overtime shift for the
drivers leading to tiredness and drowsiness. Under the influence of tiredness, he might
have pressed the TIP switch and have not recognized the elevation of the box8.. This
factor is considered as influencing, because it seduced the hitting incident of the
garbage truck on the pedestrian overpass (12).
B. 5 whys analysis of the incident:
 Why did the pedestrian overpass fall on the garbage truck?
The garbage box has elevated unnoticeably and hit the side of the pedestrian
overpass which created an impact force resulting in the fall of the floating end
pillar of the overpass.
 Why did the driver press the TIP switch?
The driver unintentionally pressed the TIP switch instead of the TOP DOOR
switch. It might be because of the dissimilarity of the incident truck with other
routine trucks or due to tiredness and fatigue.
 Why was the incident truck different from that of the usual truck used by the
driver?
The driver had to drive a different truck on Friday, unlike Saturdays, Sundays,
and Mondays.
 Why did the driver not notice the elevation of the garbage box?
Due to the change in truck and tiredness from overtime, the driver could not
notice the garbage box.
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 Why did the driver against the company policy on the public highway having
PTO on?
This exception is allowed by the employer in the situation of collecting
garbage.
Corrective actions:
 The employer should provide a single type of truck to the driver all the time to avoid
confusion (11-12)
 There should not be overtime work as it increases the risk of accidents.
 Company policies and proper driving practitioners should be followed.
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