Category Archives: Root Cause Analysis – Incident Investigation

Root Cause Analysis - Incident Investigation

Freight Trains Collide Head-On in Arkansas

By Kim Smiley

On August 17, 2014, two freight trains collided head-on in Arkansas, killing two and injuring two more.  The accident resulted in a fire after alcohol spilled from a damaged rail car ignited, prompting evacuation of about 500 people from nearby homes.  The trains were carrying toxic chemicals, but none of the cars carrying the toxic chemicals are believed to have been breached during the accident.

The National Transportation Safety Board (NTSB) is currently investigating this accident, but an initial Cause Map, or visual root cause analysis, can still be built to help document and illustrate the information that is known.  One of the benefits of a Cause Map is that it can easily be expanded to incorporate information as it becomes available.  The first step of the Cause Mapping process is to fill in an Outline with the basic information for an incident.  In addition, anything that was different at the time of accident is listed.  How the incident impacts the overall goals is also documented on the bottom of the Outline.

Like many incidents, there are a number of goals that were impacted by this train collision.  The safety goal is obviously impacted by two fatalities and injuries.  The property goal is impacted because of the significant damage to the trains and freight.  The labor/time goal is impacted because of the response effort and investigation that are required as a result of the accident. Potential impacts or near misses should also be documented so the potential release of toxic chemicals is considered an impact to the environmental goal.

The second step is to perform the analysis by building the Cause Map.  To build the Cause Map, start with one impacted goal and ask “why” questions.  Each answer is added to the Cause Map.  Each impacted goal should be considered and the cause boxes should all connect at some location on the Cause Map.  Starting with the safety goal in this example, the first question would be: why were two people killed?  This occurred because there was a train collision.  The trains collided because they were traveling toward each other on the same track.  No details have been released about how the trains ended up on the same track.  The trains’ daily recorders (which provide information about the trains’ speed, braking and throttle) have been found and will be analyzed by investigators. The NTSB has stated that they will be looking into a number of factors such as the train signals and fatigue since the accident occurred late at night.

The final step in the Cause Mapping process is to develop solutions that can be implemented to reduce the risk of a similar problem recurring in the future.  Since the investigation is ongoing, talk of solutions is premature at this point.  Once more is known about the causes that contributed to this issue, the lessons that are learned can be used to develop solutions.

Root Cause Analysis - Incident Investigation

Will Factory Explosion Lead to Increased Safety?

By ThinkReliability Staff

On August 2, 2014, 75 workers were killed and about 186 were injured by an explosion at an auto parts factory in Kunshan, China. This devastating event has raised questions about worker protection and oversight in China, as well as the responsibility for manufacturers using subcontractors in China to provide a safe workplace.

The explosion can be examined in a Cause Map, or visual root cause analysis, to look at the effects, causes, and potential solutions of the issue. A Cause Map visually diagrams the cause-and-effect relationships associated with an issue. The first step in the Cause Mapping process is to determine the impact on an organization’s goals. In this case, the goals will be looked at from the broader perspective of the country of China. The safety goal was impacted due to the large number of fatalities and injuries. The regulatory goal is impacted due to the five executives that were detained (though it’s unclear for what purpose they are being held). In the wake of the disaster, 268 factories in the surrounding area have been shut down (impacting the production goal) as part of a three-month round of inspections (an impact to the labor goal).   In addition, the property goal was impacted due to the damage to the factory, the full extent of which is still unknown.

The cause-and-effect relationships resulting in these impacts to the goals are developed by asking ‘Why’ questions. The fatalities, injuries and damage to the factory resulted from an explosion. Preliminary investigation shows that it was a metal dust explosion. Dust explosions require five components to occur (as described in the dust explosion pentagon). These components are: heat, fuel, oxygen, confinement and dispersion. Oxygen and confinement are present under normal conditions. The preliminary investigation has identified a spark as the heat source (a common potential heat source in industrial settings).

In the case of a dust explosion, the fuel source is a dust, which is distributed into the air, providing a high level of surface area allowing the fuel to become explosive (dispersion). The process being performed at the plant, which manufactures wheels for a car manufacturer, was electroplating/ polishing hubcaps. At the time, the workers were polishing hubcaps, a process that is known to create metal dust that can lead to dust explosions if safety regulations aren’t carefully followed. Specifically, safety regulations protecting against dust explosion involve cleaning and ventilation. The preliminary investigation found a shortage of equipment that is used to remove dust.

Unfortunately, that’s not too surprising. Industrial accidents kill tens of thousands of people a year in China, which has generally demonstrated a lack of regard for safety. Regulations involving dust are insufficient (and insufficiently enforced) by both the government and the manufacturing companies that subcontract work to Chinese firms (and generally outsource oversight to their contractors). Subcontractors who make small, low-value parts find themselves under heavy pressure to cut costs in a competitive market. According to Geoffrey Crothall of the China Labor Bulletin, “The explosion at the factory in Kunshan illustrates once again that although there are many laws and regulations outlining health and safety standards in the workplace those standards are not properly enforced by local authorities.”

In response to the explosion, China has detained executives from the company, and has closed 268 factories that have the potential for similar issues until they are given government permission to reopen. The government is conducting what is expected to be a three-month round of investigations of these factories and is expected to develop regulations that will better protect workers from explosive dust conditions.

The incident is drawing comparisons to the Triangle Shirtwaist Company fire in New York City which killed 146 workers in 1911. After the deadly fire, many protections were put into place that have increased workplace safety in the United States. It is hoped this tragedy will lead to a similar outcry that will force the government to act on increasing worker safety and produce lasting change.

To view the Outline and Cause Map based on the preliminary investigation, click on “Download PDF” above. Or, click here to learn more about dust explosions.

 

Root Cause Analysis - Incident Investigation

Software Glitch Delays U.S. Travel Documents

By Kim Smiley

The Consular Consolidated Database (CCD) is the global database used by the U.S. State Department to process visas and other travel documents.  On July 20, 2014, the CCD experienced software issues and had to be taken offline.  The outage lasted several days with the CCD being returned to service with limited capacity on July 23.  The CCD is huge, one of the largest Oracle-based warehouses in the world, and is used to process a hefty number of visas each year and the effects of the software glitch have been felt worldwide.  The State Department processed over 9 million immigrant and non-immigrant visas overseas in 2013 so a delay of even a few days means a significant backlog.

This issue can be analyzed by building a Cause Map, a visual root cause analysis.  A Cause Map visually lays out the different causes that contribute to an issue so that the problem is better understood and a wider range of solutions can be considered.  The first step in the Cause Mapping process is to define the problem, which includes documenting the overall impacts to the goal.  Most problems impact more than one goal and this example is no exception.

The customer service goal is clearly impacted because thousands – and potentially even millions – have had their travel document processing delayed.  The negative publicity can also be considered an impact to the customer service goal because this software glitch isn’t doing the international image of the U.S. any favors.  The delay in travel document services is an impact to the production/schedule goal and the recovery effort and investigation into the problems impact the labor/time goal.  Additionally, there are potential economic impacts to both individuals who may have had to change travel plans and to the U.S. economy because these issues may discourage international tourism.

The next step in the Cause Mapping method is to build the Cause Map.  This is done by asking “why” questions and using the answer to visually lay out the cause-and-effect relationships.  The delay in processing travel documents occurred because the CCD is needed to process them and the CCD had to be taken offline as a result of software issues.  Why were there issues with the database? Maintenance was done on the CCD on July 20 and the performance issues began shortly thereafter.  The maintenance was done to improve system performance and to fix previous intermittent performance issues. The State Department has stated that this was not a terrorist act or anything more malicious than a software glitch.  An investigation is currently underway to determine exactly what caused the software glitch, but the details have not been released at this time.  It can be assumed that the test program for the software was inadequate since the glitch wasn’t identified prior to implementation.

The final step in the Cause Mapping process is to identify solutions that can be implemented to reduce the risk of a problem recurring.  Details of exactly what was done to deal with the issue in the short term and bring the CCD back online aren’t available, but the State Department has stated that additional servers were added to increase capacity and improve response time.  There is also a plan to improve the CCD in the longer term by upgrading to a newer version of the Oracle database software by the end of the year which will hopefully prove more stable.

To view an Outline and high level Cause Map of this issue, click on “Download PDF” above.

Root Cause Analysis - Incident Investigation

Loss of Flight 17 over Ukraine

By ThinkReliability Staff

On July 17, 2014, Malaysian Airlines flight 17 was shot down 33,000′ above Ukraine by a surface-to-air missile.   The issue can be looked at in a Cause Map, or visual root cause analysis. Clearly the primary impact to the goals in this case was the death of all 298 passengers and crew members on the plane. Next the Cause Map is built by developing the cause-and-effect relationships by asking “Why” questions.

While there are multiple issues that can be discussed related to why the missile was fired at the plane, the solutions that would result in missiles not being fired are outside the sphere of influence of most (if not all) of us. Focusing on the solutions that are within the sphere of influence of airlines, regulatory bodies, and even individual passengers allows the most effective use of time.

For this reason, we will focus on why the plane was in the area. The route that planes take is generally determined by wind, weather and congestion. There are also areas where airspace is restricted. At the time Flight 17 flew over Ukraine, the restricted airspace over the area ended at 32,000′. Just a week prior a military transport plane was shot down at 21,000′. However, the primary concern at the time was shoulder-fired missiles which generally have a range much less than 32,000′.

Beyond the political questions of what to do about an unprovoked attack on a commercial airline, airlines, their regulatory bodies, and even passengers are trying to determine how they can stay safe while flying near or through one of the 41 currently designated “kinetic conflicts” (essentially areas where people are shooting at each other, causing a potential risk to planes, though generally not those flying at typical levels of commercial airliners).

Regulatory bodies, including the International Civil Aviation Organization (ICAO, the air-safety arm of the United Nations), are now looking at “the respective roles of states, airlines and international organizations for assessing the risk of airspace affected by armed conflict.” Currently each government determines the risk and whether airspace should be restricted. Air-safety experts say Ukraine’s restrictions weren’t unusual. Says air-safety consultant John Cox, “There has never been an airliner shot down from a surface-to-air missile at this kind of altitude. The threat has always been a shoulder-fired missile from insurgents.”

Individual airlines are also considering what they can do to reduce their risk. Some airlines are even considering antimissile devices, which use laser beams to draw heat-seeking missiles away from the plane itself. However, these are only effective against shoulder-fired heat-seeking missiles, not the type of missile that brought down flight 17. While many countries use these types of protection for their military planes, only Israel has required their use on commercial airliners.

For individual passengers who are concerned about the route their plane may be taking, flight-tracking services will allow them to see the flight paths of the most recent flights. However, because of gaps in coverage, flight paths over certain areas (such as over North Korea) may not be accurate. Airlines are being pressured to release their typical flight paths.

Even with the attack on flight 17 and the loss of two other planes (TransAsia Airways 222 and Air Algerie flight 5017 crashed on July 23 and July 24th, respectively, both in remote areas in poor weather), industry experts assure passengers that flying is still safe and that crashes are declining worldwide. The aviation accident rate is 2.8 per one million departures, the lowest since ICAO started tracking numbers. So far in 2014 there have been 70 commercial-plane crashes compared to 81 for the comparable period last year. (There were a total of 90 commercial flight crashes in 2013, compared to 99 in 2012 and 118 in 2011.) According to director of safety at aviation consultancy Ascend, “Having three accidents together doesn’t tell you anything about safety. It’s about the long-term trend. Airline safety is improving, and it is generally improving faster than the industry is expanding.”

To view the outline, Cause Map, and solutions, please click on “Download PDF” above. Read about more aviation safety incidents:

Malaysian Airlines Flight 370

Air Traffic Control system confusion affects hundreds of flights

Smoke at FAA facility results in flight disruptions

Asiana flight 214

Root Cause Analysis - Incident Investigation

Deadly Moscow Metro Derailment

By Kim Smiley

On July 15, 2014, a routine morning commute on the Moscow subway quickly became a nightmare when a metro train dramatically derailed, resulting in 23 deaths and about 150 injuries.  A massive rescue operation took hours and the investigation into the incident promises to be lengthy as well.

The investigation into this horrific accident is still ongoing, but an initial Cause Map can be built to capture the information that is already available and the Cause Map can be expanded as more details are known.  A Cause Map is a format for performing a visual root cause analysis.  The first step is to define the problem by filling in an Outline with the background information for the incident.  Additionally, any different or unique elements are documented because differences should almost always be investigated.  The impacts to the overall goals are documented on the bottom half of the Outline.  Once the problem is defined, the analysis is performed by asking “why” questions and using the answer to build the Cause Map. (To view the Outline and an initial Cause Map for this accident, click on “Download PDF” above.)

This safety goal was clearly impacted in this example because of the fatalities and injuries.  Why were so many hurt?  This occurred because a metro train derailed.  According to initial reports in the media, the train derailed because of an issue with a track switch mechanism that had recently been repaired.  It appears there was a problem with the repair work that was done and it can be assumed that the supervision or inspection of the work wasn’t adequate since the problem wasn’t discovered prior to the accident.

A second impact to the safety goal is that it was particularly difficult to quickly access and treat the injured passengers after the accident.  The derailment occurred at the deepest metro station on the Moscow subway, about 275 feet underground.  Rescue workers had to climb down steps to reach injured passengers and had to carry many up to the surface.

After a Cause Map is completed, the final step is to use it to develop solutions that can be implemented to reduce the risk of a similar accident occurring.  In this example, there may be changes needed to how track work is managed.  At a minimum, a careful look into how repair work is inspected prior to a track being put back into service seems warranted after this accident.

Root Cause Analysis - Incident Investigation

DELAY OF RECALL REPAIRS FIRES UP NHTSA

By ThinkReliability Staff

On June 18, 2013, the manufacturer of Jeep Grand Cherokee and Liberty sport-utility vehicles (SUVs) recalled 1.56 million vehicles due to a risk of fuel tank fires during rear-end collisions. At the time of the recall, the National Highway Traffic Safety Administration (NHTSA) linked 51 deaths to the fuel tank fires. Although a fix was accepted in January, parts won’t be available to owners until August.

The NHTSA is concerned about this delay. Says O. Kevin Vincent, NHTSA Chief Counsel, “For many owners, a recall remedy deferred by parts availability easily becomes a defect remedy denied. Moreover, additional delays in implementing this recall with inure to Chrysler’s benefit at the expense of vehicle owner safety.”

Even without full information, a Cause Map can begin to develop the cause-and-effect relationships that led to an issue. As more information is provided, more detail can be added to the Cause Map.

The analysis begins by determining the impacts to the organization’s goals. In this case, the safety goal is impacted by the 51 deaths that were determined to have resulted from gasoline fires as a result of the recall issue as well as 4 additional deaths that have occurred since the recall, according to the executive director of watchdog group Center for Auto Safety. The delay in the repairs for the recall issue can also be considered an impact to the customer service and production goals.

Beginning with one of the impacts to the goals, asking “why” questions builds the Cause Map, a visual root cause analysis. Beginning with the deaths that have occurred as a result of the recall issue since the recall took place, asking “why” questions helps determine that the deaths resulted from the issue at the heart of the recall (the increased risk for gasoline fires) and the delay in repairs from the recall. (Had the repairs been implemented more quickly, the number of deaths as a result of the issue may have been reduced.)

The increased risk of gasoline fires occurs from an increased risk of fuel tank rupture in the event of a rear-end collision because the fuel tank, in an unusual design, is located behind the rear-most axle, which provides inadequate protection. The fix for the recall issue is to add a trailer hitch, which provides an additional distance between another vehicle and the fuel tank in a rear-end collision (but it should be noted will protect only against “lower to medium-speed rear-end crashes”).

Although the addition of trailer hitches was recommended by the manufacturer at the time of the recall, a supplier was not selected until December. The manufacturer has stated that it was finding new suppliers to deal with the higher-than-normal demand for these parts. It’s also possible that the manufacturer was waiting for the NHTSA to approve the fix, which occurred in January. The NHTSA was doing additional testing to ensure that the fix would be effective. After the supplier was selected, it took nearly two months for a purchase order to be issued and five months for production to begin. The reasons for this part of the delay are unknown, and are expected to be provided to the NHTSA near-term.

The delay starting production is one thing; another concern is the amount of time it will take before enough parts are available. The supplier originally selected could manufacture 1,323 Liberty trailer hitches and 882 Grand Cherokee trailer hitches a day, meaning that if all 1.56 million vehicle owners participated in the recall, it would take 4.7 years to produce enough trailer hitches. Currently, legal requirements are only that manufacturers are required to make repairs in a “reasonable time”, although most manufacturers begin repairs within about 60 days of notifying the NHTSA. This case may force the NHTSA to define what a “reasonable time” actually is.

The latest update from Chrysler is that the trailer hitch supplier has increased production capacity and will be able to meet the demand by March of 2015. Chrysler also said that the NHTSA over-estimated the number of hitches required for the recall because the calculations didn’t account for vehicles that are no longer in use or those already equipped with hitches.

To view a timeline, Outline and Cause Map of this issue, please click “Download PDF” above. Or, click here to learn more.

 

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Root Cause Analysis - Incident Investigation

The Controversy Over the 2010 World Cup Ball

By Kim Smiley

Unlike other sports where the balls remain relatively constant, a new soccer ball is typically unveiled for the World Cup every 4 years.  The changes made to the balls aren’t just cosmetic; the behavior of the soccer ball can vary between designs.  One of the most controversial designs in recent memory was the Janulani, the official ball of the 2010 World Cup that was widely criticized and dubbed “the beach ball”.

The issues surrounding the Janulani soccer ball can be analyzed by building a Cause Map, a visual root cause analysis.  To build a Cause Map, “why” questions are asked to determine what factors contributed to an issue and answers are visually laid out to show the cause-and-effect relationships. To view a Cause Map of this issue, click on “Download PDF”.

So why was the 2010 World Cup ball the focus of so many complaints? Players felt that the ball was unpredictable and behaved differently than previous ball designs.  Scientists studied the Janulani ball and determined that it was less aerodynamically stable, particularly at the speeds typical for a professional free kick, which made the goalie’s job significantly harder and tempers flare.  The Janulani ball was a fundamentally different design: it had fewer panels (8 instead of the traditional 32), a smoother surface and internal stitches.  The ball was basically so smooth it changed how air flowed around it, including the speed where the transition between smooth and turbulent flow occurred.  The placement of the seams was also significantly different and not as balanced so that the ball moved erratically at times.  One can assume that the testing program for the new soccer ball design was inadequate since the changes in flight path patterns were not intentional, so that is another cause that needs to be considered.

It’s also worth noting that the fact that a new soccer ball design was used for the 2010 World Cup is a cause of the problem.  Few other sports have equipment that is changed so frequently and/or debut new equipment at major international events. So why is there a new ball for every World Cup?  Money certainly plays a role since there is a huge demand for World Cup merchandise and a new ball means a new product to sell.  The restrictions governing soccer ball design are also vague – for example, the number of panels are not specified – which allows plenty of wiggle room for innovation.

The problems with the 2010 World Cup ball seem to have been fixed and the 2014 World Cup ball, the Brazuca, doesn’t seem to be generating close to the amount of negative press.  In order to smooth out the flight pattern, this design is about a half-ounce heavier, has a slightly rougher surface and deeper seams.  There has been some speculation that the fast flying Brazuca is responsible for the high number of goals scored this World Cup, but the ball appears to fly predictably – if fast. If you want a stylish new Brazuca official match ball of your own, they are selling for $160 each.

If you are still feeling blue that the US is out the World Cup, try searching #ThingsTimHowardCouldSave.  It should cheer you up a bit.

Root Cause Analysis - Incident Investigation

Extensive Fire on USS George Washington Placed Crew at Risk

By ThinkReliability Staff

When fire broke out in 2008 on aircraft carrier USS George Washington in an unmanned space that was being used to improperly store flammable materials, it took more than 8 hours to find the source of, and extinguish, the fire. In the Navy’s investigation report, Admiral Robert F. Willard, commander of the US Pacific Fleet, stated “It is apparent from this extensive study that there were numerous processes and procedures related to fire prevention and readiness and training that were not properly functioning. The extent of damage could have been reduced had numerous longstanding firefighting and firefighting management deficiencies been corrected.”

The processes and procedures that were implicated in the investigation of the fire can be examined in a Cause Map, or a visual root cause analysis. This process begins by identifying the goals impacted. In this case, the primary goal impacted was the safety goal. Thirty-seven sailors were injured; one was seriously burned. There were no fatalities. In addition, the damage to the ship was estimated at $70 million and left the ship unusable for 3 months.

Beginning with the impacted safety goal, asking ‘Why’ questions allows us to develop the cause-and-effect relationships that led to those impacted goals. In this case, the injuries to sailors resulted from the extensive fire aboard ship. In addition, some of the affected sailors (including the sailor who was seriously burned) did not have adequate protective clothing. Specifically, liners worn underneath firefighting gear were not available in one repair locker because they were being laundered. Both the fire and the inadequate protective gear were causally related to the injuries so they are both included on the Cause Map and joined with ‘and’.

Asking additional ‘why’ questions adds more detail to the Cause Map. When investigating a fire, it’s important to include the factors that resulted in the initiation of the fire (heat, fuel and oxygen) as well as those that allowed the fire to spread. In this case, the ignition (or heat) source was believed to be a cigarette butt. On-scene evidence showed that smoking was occurring in the area, against regulation. The ship was found to have inadequate training regarding the smoking policy and inadequate control over the locations where smoking was occurring, because regular zone inspections were not being held.

The initial fuel source was determined to be refrigerant oil and other flammable materials improperly stored in an unmanned space where the fire began. The oil was not turned in as required by procedure over a concern about the difficulty of retrieving it. Because the oil was never entered into the inventory control system, the storage discrepancy was not noted. The unmanned space in which it was stored was not inspected. Unmanned spaces were not included in zone inspections and the area had not been designed as a tank or void to be identified in the void and tank inspection.

Once a fire breaks out, the speed in which the source is found and extinguished has the most impact on the safety of personnel. In this case, the source of the fire was not found for eight hours.   Not only did the fire begin in an unmanned area, the drawings showing the layout of the ship were inaccurate, because the ship was in the midst of alterations.

Developing the causes the resulted in the impacted goals allows for identification of all the processes and procedures that need to be re-examined to reduce risk of recurrence. In this case, the report identified multiple processes and procedures that were re-evaluated in the wake of the disaster, including those for hazardous material storage, training, inspection and firefighting.

To learn more, click here to read the Navy investigation report. To view a one-page overview of the Outline and Cause Map, please click on “Download PDF” above.

Root Cause Analysis - Incident Investigation

Can a “Super Banana” Reduce Vitamin A Deficiency?

By Kim Smiley

Vitamin A deficiency is rare in developed countries, but it remains a major public health issue in more than half of all countries, particularly in especially in Africa and South-East Asia. Researchers at the Queensland University have created a “super banana” genetically engineered to contain alpha- and beta-carotene that they hope will reduce vitamin A deficiency in parts of the world where bananas are a staple crop.

The problem of vitamin A deficiency can be analyzed using a Cause Map, a visual format for performing a root cause analysis. A Cause Map is built by determining how an issue impacts the overall goals and then asking “why” questions and laying out the answers visually to show the cause-and-effect relationships. In this example, the overall goal of public safety is impacted because vitamin A deficiency causes 650,000 – 700,000 deaths and results in blindness in 250,000-500,000 children annually. This occurs because the body, especially growing bodies, needs vitamin A to function properly and the diet does not contain adequate vitamin A.

Bodies use vitamin A in a number of ways. For example, vitamin A is important for healthy vision and a lack of it will result in blindness.  It has been shown to play an important role in the immune system. Diets in some regions of the world lack enough vitamin A because they are poor subsistence-farming communities that predominantly consume locally grown crops and the local crops don’t contain sufficient vitamin A.

There have been a number of different ways to help reduce the occurrence of vitamin deficiency such as distribution of vitamins and introduction of new crops, but the problem of vitamin deficiency is still a widespread issue which led to the idea of genetically modifying local crops to be more nutritious. The idea behind the “super banana” is that they would look the same as other East African Highland bananas and grow in the same conditions, but that they would be enriched with additional nutrients. The inside of the “super bananas” is more orange than regular East African Highland bananas, but the outside looks the same.

Lab tests with gerbils have been successful and the first human trials of the modified bananas are scheduled starting this summer. If the human trials are successful, the next necessary step is for Uganda’s legislature to approve a bill allowing the crops to be grown. Researchers are hoping to have the modified bananas growing in Uganda by 2020 if the government approves the project.

To view a high level Cause Map, click on “Download PDF” above.

Root Cause Analysis - Incident Investigation

Fingertips Amputated After Slip on Ice

By ThinkReliability Staff

Information on a slip that caused severe damage to an electrical contractor in Newcastle in August 2013 was recently released by Great Britain’s Health and Safety Executive (HSE). Though this incident didn’t make the front pages of the newspaper, it is representative of many of the injury investigations which we facilitate using the Cause Mapping method.

The first step in the Cause Mapping method of root cause analysis is to capture the what, when and where of the incident and the impacts to the organizational goals. In this case, the what (contractor slip and hand injury), when (August 30, 2013) and where (a moving conveyor at a baguette manufacturer in Leeds) are captured, as well as any differences and the task being performed at the time of the incident. There were two notable differences during the incident as compared to an “average” day that should also be noted: the safety guard had been removed from the conveyor and ice had accumulated on the floor. These differences may or may not be causally related to the incident. Additionally, the task being performed (cleaning up after contract electrical work) is captured as it, too, may be causally related to the incident.

The impacts to the goals are analogous to what stood in the way of a perfect day. A serious injury involving the partial amputation of two fingers and the injury of a third is an impact to the safety goal in this example. The £8,500 fine levied by the HSE is an impact to the regulatory goal. The worker had four weeks off work due to the injury, which is an impact to the labor goal. It is unclear if any other goals were impacted by this incident.

Once at least one impact to the goals has been determined, asking “why” questions helps us complete the second step, or analysis. In the analysis, we capture cause-and-effect relationships that map out the issues that led to the incident. In this case, the injury was caused by the contractor’s hand striking an unprotected drive chain on a moving conveyor. This occurred because the hand struck the area, the drive chain was unprotected, and the conveyor was moving. All three of these causes had to occur for the resulting injury.

The contractor’s hand struck the area because of a slip on an icy floor. Ice from an open freezer door (which appeared to be malfunctioning) had built up and had not been removed.   The drive chain was unprotected because the safety guard had been removed from the conveyor, which was moving likely due to normal operations.

According to Shuna Rank, the HSE inspector, “This worker’s injuries should not and need not have happened. This incident was easily preventable had Country Style Foods Ltd ensured safety guards were in place on the machinery. The company should also have taken steps to prevent the accumulation of ice on the freezer floor. Guards and safety systems are there for a reason, and companies have a legal duty of care to ensure they are properly fitted and working effectively at all times. Slips and trips are the biggest cause of major injuries in the food and drink industry with 37% of all major accidents in the industry being as a result of slips.”

The inspector’s quote clearly identifies the areas for improvement that could reduce the risk of similar incidents occurring. Namely, the manufacturer must ensure that damage resulting in ice buildup is fixed as soon as possible and that in the meantime, ice is regularly cleared away and the area is marked as a slip hazard. If a safety guard is removed for any reason, the conveyor should not be operating until it has been replaced properly. Ensuring that equipment is in proper working order is essential to reduce the risk to workers such as the injuries demonstrated in this case.

To view the Outline and Cause Map, please click “Download PDF” above. Or click here to read more.