All posts by ThinkReliability Staff

ThinkReliability are specialists in applying root cause analysis to solve all types of problems. We investigate errors, defects, failures, losses, outages and incidents in a wide variety of industries. Our Cause Mapping analysis method of root causes, captures the complete investigation with the best solutions all in an easy to understand format. ThinkReliability provides investigation services and root cause analysis training to clients around the world and is considered the trusted authority on the subject
Root Cause Analysis - Incident Investigation

50 Presumed Dead in Canadian Train Disaster

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By ThinkReliability Staff

A tragic accident devastated the Canadian town of Lac-Mégantic, Quebec on July 6, 2013.  Much about the issue is still unknown.  When investigating an incident such as this, it can be helpful to identify what is known and information that still needs to be determined.

What is known: a 73-car train was parked in Nantes, Quebec, uphill from Lac-Mégantic.  Of the cars, 72 contained crude oil.  The train was left unattended and late the evening of July 5, 2013, a fire broke out in the locomotive.  While the fire department of Nantes was putting out the fire, they turned off the train’s main engine.  Less than two hours later, the train rolled down the track and derailed in Lac-Mégantic.  After subsequent explosions and long-burning fires, 24 people have been confirmed dead.  26 more are missing.   Much of the town and the train – and the evidence in it – is destroyed.

What is not known: The cause of the initial fire on the train is not known.  Whether or not the fire department should have explicitly notified the train engineer that the main engine had been shut off is not known.  What happened that allowed the train to roll downhill is unknown.

With this number of unknowns, it is helpful to visually lay out the cause-and-effect relationships that occurred, and what impact they had on those affected.  This can allow us to see the holes in our analysis and identify where more evidence is needed.  Once as much evidence as possible has been obtained, additional detail can be added to the cause-and-effect relationships.  Ensuring that all causes related to the incident are included will provide the largest number of solutions, allowing us to choose the most effective.  We can do all this in a Cause Map, or visual root cause analysis.

The first step in using any problem solving methodology is to determine the impact caused by the incident.  In this case, the deaths (and assumed deaths) are our most significant impact.  Also addressed should be the crude oil leakage (though much of it was likely burned off), the high potential for lawsuits, the possible impact on rail shipments, the destruction of the town and the train, and the response and cleanup efforts.  These form the initial “effects” for our cause-and-effect analysis.

Asking “Why” questions allows us to further develop the cause-and-effect relationships.  We know that for the train to roll backwards down the hill, both sets of brakes had to be ineffective.  The railway company has stated that the air brakes released because the main engine had been shutdown.  However, according to the New York Times, “since the 19th century, railways in North America have used an air-braking system that applies, rather than releases, freight car brakes as a safety measure when it loses pressure.”  This certainly makes more sense than having brakes be dependent on engine power.

The hand brakes functioned as backup brakes.  The number of cars (which, when on a hill, affects the force pulling on the train) determines the number of handbrakes required.  In this case, the engineer claims to have set 11 handbrakes, but the rail company has now stated that they no longer believe this.  No other information – or evidence that could help demonstrate what happened to either sets of brakes – has been released.

Also of concern are the style of train cars – believed to be the same that the NTSB identified in a report on a previous train accident as “subject to damage and catastrophic loss of hazardous materials”.

In a tragedy such as this one, the first priority is to save and preserve human lives in every way possible.  However, once that mission is complete, evidence-gathering to determine what happened is the next priority.  As evidence becomes available it is added directly to the Cause Map, below the cause it supports or refutes.  Additional causes are added as necessary with the goal of determining all the cause-and-effect relationships to provide the largest supply of possible solutions to choose from.

The company involved has already stated it will no longer leave trains unattended.  That should be a big help but, given the consequences of this event, other solutions should be considered as well.

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

Root Cause Analysis - Incident Investigation

Train Derails After Collapse of Bridge in Calgary

By ThinkReliability Staff

Emergency crews in Calgary, already overworked from the heavy flooding in the area, have another potential emergency to mitigate.  In the very early morning of June 27, a rail bridge over the Bow River collapsed, just as the end of a long train went across.  The last six cars – five of which contained petroleum products, the last empty – derailed and are now precariously balanced on the collapsed bridge (but remain out of the river).

Emergency plans have been implemented to reduce the risk of the public in the area.  Capturing the cause-and-effect relationships that are resulting in the risk to the area can show how the emergency actions are acting on causes and potential causes to keep the public and the environment safe.  A visual representation of this type of root cause analysis is called a Cause Map.  The Cause Map has three steps.

First, we capture the what, when and where of the incident in a problem outline.  We also capture any differences such as the heavy recent flooding in the area.  Differences that we capture may or may not turn out to be causally related to the problem, but investigating the possibility is important.

The remainder of the outline is the impact to the goals.  Any “problem” is in fact an impact to one or more of an organization’s goals.  Framing the problem with respect to an organization’s goals ensures that solutions act to reduce these impacts and decrease disagreement about what the problem really is.  In this case, the safety goal is impacted due to the potential for injuries (though there have not been any associated with the derailment or response yet).  The potential leak of petroleum products is an impact to the environmental goal.  The area surrounding the train was evacuated, which can be considered an impact to the customer service goal.  (Frequently organizations will consider the surrounding communities as part of their customer base.)  The production/schedule goal is impacted because the bridge is unusable.  The damage to the bridge and potential damage to the cars (as yet unknown, because of their unstable position) are impacts to the property/materials goal. Lastly, the manpower being spent on emergency response and securing the train cars is an impact to the labor/time goal.

Once the impacts to the goals have been determined, the analysis begins with these impacted goals and is continued by asking “Why” questions.  For example, the risk of injury is caused by the potential leak of petroleum products.  The potential leak is due to the potential damage to the rail cars and the product contained within 5 of the cars.  Removing either of these causes reduces the risk of the effect.  In this case, plans are being made to remove the product from the trains to reduce the risk of both the safety and environmental impact.  The rail cars are being secured so that further bridge collapse will have less impact on the structural stability of the cars.

The evacuation – removing the people from the area – also serves to reduce the risk of injury.  To reduce the potential environmental impact, booms have been installed down-river in case of product leak.  Of course, these are emergency, short-term solutions designed to reduce the impact of collapse and derailment.  Solutions to the issue of the bridge collapse and its causes will be looked at in more detail once the cars have been safely removed.

While the investigation of the issue is still ongoing, the information that is currently known can be added to the Cause Map.  The structural failure that led to the bridge collapse appears to be caused by scouring of a support pier caused by the sudden influx of water related to the flooding in the area.  Concerns about how quickly the damage was discovered are a concern.  While investigations had been stepped up as a result of the flood, concerns from the city – which does not have jurisdiction for its own inspections – that the rail company’s inspections were insufficient will certainly be investigated.  It’s also been determined that the bridge – unlike others in the area – was not built into the bedrock, decreasing its strength, though how much of a role that played in the collapse  is yet to be determined.  When more information is known, it can be added to the Cause Map.

To view the Outline and Cause Map, please click “Download PDF” above.

Root Cause Analysis - Incident Investigation

Failure of the Teton Dam in 1976

by ThinkReliability Staff

On June 5, 1976, workers were called to the Teton Dam on the Teton River in Idaho to attempt to repair a leak.  Workers in bulldozers narrowly avoided being sucked into the dam with their equipment, and watched helplessly as the dam was breached.  It would kill 14 people and cause nearly hundreds of millions of dollars in property and environmental damage.  To examine what went wrong, we can perform a visual root cause analysis, or Cause Map.

The Cause Mapping process begins by determining the impacts to an organization’s goals.  From the perspective of the government, specifically the Bureau of Reclamation, the safety goal is impacted because of the 14 deaths.  The environmental goal is impacted due to the severe impact the dam failure and subsequent flooding had on the ecosystem of the area.  The customer service goal was impacted due to the evacuation of three towns.  The production goal is impacted due to the abandonment of the dam – at a cost of approximately $50 million.  Additionally, property damage of at least $400 million (some estimates are much higher) is an impact to the property goal.  (There were also substantial claims related to the loss of property and livelihood from impacts to industries, particularly fishing.)

Once we have determined the impacts to the goals, we begin with an impacted goal, such as the safety goal, and ask “Why” questions to determine the cause-and-effect relationships that led to the impacted goals (also known as “problems”.)  In the case of the Teton Dam failure, people were killed due to a massive wave of water released from the dam (which was filled to capacity) when it failed.  The dam failure was also the cause of severe damage to the dam, which was never rebuilt, leading to the impacted production goal.

The failure of the dam was found to be caused by erosion and inadequate strength.  Due to the less than ideal geological conditions of the site (which was picked because there were no “good” sites available), unequal stress distribution and inadequate fill material (which was used from the site) led to reduced strength.  Susceptible materials and seepage from leaks in the embankment, caused by joints that were not resistant to water pressure due to inadequate testing, and inadequate protection from water due to an over-reliance on an ineffective curtain intended to stop flow, led to the erosion.

Many geologists had predicted problems with the dam before it was built.  Specifically, in his book “Normal Accidents”, Charles Perrow states “The Bureau ignored its own data that rocks in the area were full of fissures, and in addition they filled the dam too fast . . . All it takes to bring a dam down is one crack, if that crack wets the soil within the interior portions of the dam, turning it into a quagmire.”

Although tragic, and expensive, the failure of the Teton Dam did lead to many reforms in the Bureau of Reclamation, who is responsible for dam safety.  Detailed geological studies performed in order to determine the causes of the dam failure also provided additional insight to the strength provided by various types of earth, erosion and seepage.

Root Cause Analysis - Incident Investigation

Update: Cause of Death of Schoolchildren from Tornado in Moore, Oklahoma Not Drowning

by ThinkReliability Staff

Although they are sometimes treated as a static object, Cause Maps (and any root cause analysis) can – and should – change based on updated or corrected information.  A frequent question we get asked is “What if I make a mistake on my Cause Map?”  Well, you fix it.  Let me show you how.

First, a little background on my error.  Last week, I thought it would be important and useful to demonstrate what had happened in the aftermath of Moore, Oklahoma, after a category 5 tornado hit much of the town, including an elementary school.  (See the previous blog.)  Because there are certain expectations for public safety at an elementary school, I decided to focus the analysis on the children who died at the elementary school and the causes that led to their deaths, as well as information on the potential and implemented solutions to reduce that risk.

I researched how specifically the children had died – an unfortunate necessity to ensure that the solutions are working towards the correct causes – and discovered a statement from the Lt. Gov. of Oklahoma the morning after the tornado saying that the children who died had drowned in the basement due to a burst water main.

As you can imagine, sometimes information that is relayed in the immediate scene of a disaster is not entirely accurate.  In this case, the information that the children had drowned was incorrect.  Rather, the children who died were in a classroom and died from blunt force trauma and asphyxiation (suffocation) due to being struck or covered by debris from the tornado.

Once we have verified that our initial cause-and-effect relationship is incorrect, we can correct the Cause Map.  Rather than just erasing the “wrong” causes and adding in the new causes, we suggest crossing off the causes that have been disproved with evidence.  (Click on “Download PDF” above to see an example of a corrected Cause Map.)  This way anyone who may have seen an earlier version of the Cause Map, or heard the same initial erroneous information that was used to make it, will have a clear version of what did happen, including the evidence that verifies the correct information.

Obviously the fact that the children died is tragic, so some may wonder what difference it makes exactly how they died.  Generally people who are killed in tornadoes are killed by objects striking them.   This is why tornado survival drills focus on getting to spots where there is the least possible dangerous debris, or the least risk of the debris becoming dangerous flying objects. Windowless rooms are recommended, because glass can be broken and easily turn into shrapnel.  Basements are recommended because the strong winds associated with tornados have less access to underground areas.  Bathrooms are another option because most everything in a bathroom is secured to the walls and/or floors.  In a pinch, people seek protection under heavy pieces of furniture.  (Survivors from the affected school have said that they hid under their desks and held on for dear life.)

Because the basement is a recommended sheltering location, the possibility of drowning from  equipment that may be damaged by a tornado meant that the basement needed to be reconsidered as a sheltering location.  Because the school did not have a designated safe room, during the 16-minute warning teachers got their students to anywhere they could, including, in many cases, under their own bodies for protection.  (Again, based on the extreme damage to the school the death toll, while tragic, demonstrates the remarkably quick and effective action  taken the teachers.  I can’t emphasize this enough.)  Because this protection was very likely causally related to the death toll (in that without the amazing response from the teachers the death toll may have been much higher), I added additional evidence to the cause of injury.

Be aware that changing the causes may impact the recommended solutions.  The solutions discussed in the previous blog are still valid, especially the recommendations for inclusion of storm shelters for schools in the area.  An additional clarification added in the update is that this has been required since 1999 (after this school was built).  All the schools being rebuilt as a result of the tornado damage will have storm shelters, as will schools built in the future.  Individual communities will still be faced with the choice of which buildings will and will not be required to have storm shelters, and any incentives that will be put into place to encourage their construction.

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

Root Cause Analysis - Incident Investigation

Children Killed When School Hit by Category 5 Tornado

by ThinkReliability Staff

A category 5 (the most destructive) tornado hit Moore, Oklahoma on May 20th, destroying the town and killing 24.  Of those killed, 7 were elementary school children, who drowned when water mains burst in the basement where they were sheltered.

Examining this tragedy can help provide lessons to reduce the risk of this issue happening again.  We can analyze the tornado impact at the most severely impacted elementary school in a Cause Map, in order to visually diagram the cause-and-effect relationships that led to the tragic deaths.

First, we determine the impacted goals.  In this case, all other goals are overshadowed by the deaths of seven  elementary students, and injuries to dozens.  In addition, the school was completely devastated (demonstrating the unbelievable destructive power of the tornado), resulting in early school closure and intense rescue, recovery and cleanup.

To perform our root cause analysis, we begin with the safety goal and ask “Why” questions.  The deaths in this case are reportedly due to drowning, which occurred when children in the basement (a recommended sheltering location in the case of tornadoes) drowned due to water from bursting water mains.  The specific failure mechanism of the failure is not known (and may never be due to the extreme levels of damage) but is likely related to the direct strike of the tornado, which is common in the area (close to the center of tornado alley).

Students who were injured by crushing and asphyxia were in the hallways and bathrooms of the school.  (These are recommended sheltering locations for buildings that don’t have basements.)   It is remarkable that, despite the complete annihilation of the school, students who were sheltered in hallways and bathrooms all survived, thanks in many cases to teachers protecting them with their own bodies.  A 16-minute warning from the National Weather Service combined with carefully rehearsed crisis plans that were put into action, allowed the best possible protection for students in a school without a safe room or storm shelter.

This storm has reignited the discussion about expectations for safety shelters in public places that are prone to natural disasters.  The devastating loss at the school has also raised the safety issue of ensuring that the locations used for shelter are cleared of other potential hazards, such as water mains and fire risks.  Because of the relatively short warning time (16 minutes in this case, which is above average) before a tornado strikes, emphasis on tornado drills and safety plans should continue.

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

Root Cause Analysis - Incident Investigation

The Comet That Couldn’t Fly

By ThinkReliability Staff

“… the most exhaustively tested airplane in history.”

-Expert opinion on the DeHavilland Comet

Today, commercial jet air travel is standard fare. Estimates for the amount of air traffic over the United States in a given day have been in the range of 87,000 flights. With clever planning, clear skies and smooth service, a citizen almost anywhere in the world can get anywhere else by plane in less than 24 hours. But looking back at the history of aviation show us how far safety has come. Consider the DeHavilland Comet, the first commercial jet to reach production. British aviation specialists finalized the Comet’s design with much excitement in 1945 in hopes it would position their industry to establish a revolutionary service in commercial jet flight. Unfortunately, the Comet crashed on January 10th and April 8th in 1954.

What happened? We can identify some of the causes in a Cause Map, or visual root cause analysis.

CAUSE #1: POOR TESTING When you test an extremely heavy object carrying hundreds of people at high speeds thousands of feet above the ground, you would think planning for the worst case scenario would make the most sense. Unfortunately, the Comet tests were performed in tainted conditions on the strongest part of the plane.

Add in the fact that there was no prototype for the plane and you’ve got a test not worth having… and a plane not worth flying.

CAUSE #2: UNEXPECTED PRESSURE Altitude leads to pressure, and pressure puts stress on planes. But this stress wasn’t evenly distributed, and certain parts of the planes’ bodies were unevenly affected. So rather than the expected amount of pressure on the planes, the Comets faced an unforeseen squeeze.  

CAUSE #3: FLYING ABOVE AND BEYOND The Comet flew at twice the speed, height and cabin pressure of any previous aircraft, displaying a rather dangerous amount of ambition.

Combine all of this, Cause Map it, and you’ve got a plane flying under incredible conditions it couldn’t withstand, facing high pressure where it was most vulnerable.

In other words, an airborne recipe for disaster.

FALLOUT #1) SAFETY As expected, the pressure cycle in the planes’ cabins cracked the bodies of the planes. When the planes broke up, the lives of 56 passengers and crew members were lost.

#2) CUSTOMER SERVICE Some British industry institutions have a highly prestigious reputation (the Royal Navy’s impact on British sea travel comes to mind). The loss of the aircraft, though, was a black eye on British Aviation. Aviation historian George Bibel called the Comet an “adventurous step forward and a supreme tragedy.”

#3) MATERIALS/LABOR Effective airplanes have never been cheap, and this was no different. Not only would it cost money to investigate the cause of the accidents, but to replace the airplanes.   

FUTURE SOLUTION The Comet’s tragic crash had one silver lining: the post-crash analysis performed by its designers (including Sir Geoffrey de Havilland) set the precedent for future air accident investigations. In fact, the Comet was redesigned to solve the issues that caused the crashes and would later fly successfully. But by then, Boeing had already taken over most of the commercial jet market.

In the end, the Comet was first in flight but last in the market.

See more aviation cause maps:

Want us to cause map a specific plane crash for you? Tell us in the comments and we’ll pilot our way through it.

Root Cause Analysis - Incident Investigation

Unticketed Man Bypasses Security, Boards Plane

by ThinkReliability Staff

On May 29, 2012 a man boarded a flight from the tarmac at San Diego International Airport.  The man did not have a ticket, and had not been through security.  The extra passenger was not noticed until a flight attendant’s head count was noted to be off.

We can examine this issue in a Cause Map, which is a root cause analysis that visually represents the cause-and-effect relationships that result in impacts to the organization’s goals.  We begin by defining what those impacts to the goals were.  In this instance, although no one was hurt, there was the potential for a safety issue.  The customer service goal was impacted due to the deplaning required for the passengers already onboard.  The schedule goal was impacted because the plane was delayed due to the rechecks required of passengers.  The personnel time required for these rechecks is an impact to the labor goal.

Once we’ve determined the impacts to the goals, we ask “why” questions to determine the causes resulting in the impacted goals.  In this case, the rechecks were required because the flight attendant’s head count was off.  The flight attendant’s count was off because a man without a ticket had boarded the plane.   Because the man was able to board the plane from the tarmac without showing a ticket, tickets were presumably not checked at the aircraft door.  Likely they were instead checked at the door leading to the tarmac.  Because the unticketed man was able to access the tarmac through an emergency exit, he was able to get on the plane without a ticket.  How was he able to access the tarmac?  He went through an emergency exit door in a public area.  Security did not realize that he had exited this way, either because there was no alarm associated with using the door, or the notification from the alarm was inadequate to ensure that security was notified.

According to San Diego Harbor Police Chief John Bolduc, “He completely bypassed TSA screening.  He was in a public area and went out an emergency fire door, which gave him access to the tarmac.”

The airport is carefully scrutinizing its security to ensure that this never happens again.  One solution would be to install emergency exit alarms so that security personnel are notified that security bypass procedures should be initiated.  A solution for the plane operators is to check tickets at the door of the plane, in addition to or instead of at the exit to the tarmac.

To view the Outline, Cause Map and potential solutions, please click “Download PDF” above.

Root Cause Analysis - Incident Investigation

The Collapse of Agricultural Buildings

By ThinkReliability Staff

Every winter there are pockets of agricultural building collapses in areas that have seen heavy snow and ice accumulation.    The causes for these collapses can be examined in a Cause Map, or visual root cause analysis.  First, we begin by capturing the basic information about the issue.  In this case, there  were three areas that suffered building collapses due to winter weather accumulation.  This included New  York State in 1999,  Wisconsin in 2010, and England in 2010 and 2011.  Important to note is that each of these areas experienced heavy snowfall during the periods of collapse and in each region, agricultural buildings were more likely than other types of buildings to have collapsed.  It is also important to note that in each of these areas, agricultural buildings were not regulated to the same level as other buildings.

To begin our root cause analysis, we begin with the impacts to the goals. The collapse of an agricultural building carries with it the risk of human injury or loss of life, as well as potential loss of livestock.  A building collapse results in property damage as well as time spent on cleanup, repairs, and anything else that needs to be done to get the facility up and running again.

To continue the analysis, we begin with the impacted goals and ask “why” questions.  These impacts to the goals are all related to the collapse of an agricultural building.  The collapse of a building results when the stress (in this case, the structural load) exceeds the strength.  The structural loads in the case of the collapsed buildings generally result from accumulation of ice and snow, which  may be unevenly distributed, increasing local load, due to drifting, and an improperly engineered building.  Agricultural buildings are more likely to collapse due to structural loads because they are exempt from codes in most of the US and unregulated in England.  If engineering is desired, a properly engineered building may be scaled up or altered, resulting in changing loads and strengths, meaning the engineering review may no longer be valid to protect the building.  Although engineering is frequently skipped due to cost measures, experts say that proper engineering can save money by ensuring that supports are put in only where they’re needed (and, of course, reducing the risk of a collapse.)

Generally the collapsed buildings are found to have inadequate bracing, which reduces the strength of the building to the point of collapse.  If the buildings are not properly engineered, bracing may be inadequate for the design of the building.  Another issue  frequently seen is that the trusses are engineered, but are not reviewed with respect to the overall building design, leading to an insufficient analysis that does not take into account all of the factors that impact building loads and strength.

Although states and countries could elect to consider agricultural buildings in their codes, farmers don’t need to wait.  If you are building an agricultural building (or any building that may be exempt from code), ensure it’s adequately structurally engineered.  It may save a life.

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

1999 collapses in NY State

2010 collapses in Wisconsin

2010 & 2011 collapses in England

Root Cause Analysis - Incident Investigation

$3 Bolt Causes $2.2 million in Damages to US Submarine

By ThinkReliability Staff

A $3 bolt was left in the main reduction gear of the USS Georgia after a routine inspection.  The extensive damage caused by the bolt resulted in 3 months in the shipyard for the submarine, causing it to miss deployment.  The propulsion shaft was left to operate for two days after sounds indicated that there was something wrong.  This may have increased the damage to the main reduction gear – damage which cost $2.2 million.

How did the bolt end up in the main reduction gear? Why was the propulsion shaft operated for 2 days after damage was suspected?

We can look at the causes that led to this incident in a Cause Map, a visual root cause analysis that clearly outlines cause-and-effect relationships that result in impacts to an organization’s goal.  The first step to building a Cause Map is to determine how the issue impacts the organization’s overall goals.  Here we can consider the US Navy as the organization.  The customer service goal (with the rest of the country as the “customers”) was impacted because the submarine was unavailable for deployment.  The production/schedule goal was impacted because the submarine was in the shipyard for  three months.  The damage to the main reduction gear is an impact to the property goal, and the repairs are an impact to the labor/time goal.  The total cost resulting from this issue was estimated to be $2.2 million.  Once the impacts to the goals have been determined, we can ask why questions to put together the cause-and-effect relationships that led to these impacts.

The bolt was left behind after a routine, annual inspection.  Because of the great potential for damage when foreign objects remain within equipment, detailed procedures are used for these inspections and include a log of all equipment brought into the area and a protective tent to keep objects from falling in.  Details of what went wrong that resulted in the bolt falling into the main reduction gear were not released, but the inspection was reported to have “inadequate prep and oversight” which likely contributed to the issue.

After the propulsion shaft was turned back on, noise indicated that there was a problem.  However, the shaft was operated for two days in a failed attempt at troubleshooting.  It’s likely that this increased the damage to the main reduction gear.  It is unknown what procedures were – or should have been – in place for troubleshooting, but the actions taken as a result of this incident suggest that proper procedures were not followed once the damage was suspected.

In this case, members of the crew who were found to not have performed their job – possibly by not following proper procedure – were punished in varying ways.  It is likely that the investigation went into great detail about whether procedures were adequate, what steps were not followed, and why, and the results also used to improve procedures for the next inspection.

To view the Outline and Cause Map, please click “Download PDF” above.

Root Cause Analysis - Incident Investigation

Fire kills 146, Leads to Improved Working Conditions

By ThinkReliability Staff

146 workers were killed when a fire raced through the Triangle Company, which occupied the top three floors of a skyscraper in New York City.  The workers were unable to escape the fire.  We can examine this incident using a Cause Map, a visual form of root cause analysis, which allows us to diagram the cause-and-effect relationships that led to organizational issues – in this case, the death of 146 workers.

On March 25, 1911 at approximately 4:40 p.m., a fire began on the 8th floor of a New York City skyscraper (one of three floors housing the Triangle Waist Company).  Although it’s not clear what sparked the fire (cigarettes and sewing machine engines are likely heat sources), a large amount of accumulated scraps (last picked up in January) provided plenty of fuel.  There were no sprinklers and the interior fire hose was not connected to a water source.  The fire spread quickly and burned for approximately a half an hour before firefighters extinguished it.

During that half-hour, 146 workers, mostly young women, were killed.  Nearly all of these workers were from the 9th floor of the building.  Workers from the 8th and 10th floor were able to escape to the ground or roof using the stairs, but one of the access doors on the 9th floor was locked.  This left only one set of stairs and elevators, which did rescue many but were overcrowded and the elevator machinery eventually failed due to heat.  Many attempted to escape using the fire escape, which was not built for quick escape (in fact, experts determined it would take 3 hours to reach ground from the Triangle Company floors) and eventually collapsed due to the collective weight, killing those on it in the fall.

Many workers jumped from the 9th floor, but the force of the fall was too great for the fire nets, which mainly broke and the jumpers died.

People were horrified at the conditions in the factories that resulted in these deaths.  In the following years, public outcry resulted in many workers’ rights improvements, including many advances in regulations regarding fire protection and working conditions.  However, these types of issues continue in other countries that have not defined such requirements.

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