Tag Archives: Cause Mapping

Root Cause Analysis - Incident Investigation

Commuter Ferry Crash in NYC Injures 85

By ThinkReliability Staff

A commuter ferry struck a pier in Lower Manhattan, NY during the morning commute on January 9, 2013, injuring at least 85 people – some critically .  According  to US Coast Guard Captain Gordon Loebl, “We know that they hit the pier at a relatively high rate of speed.”

We can examine this issue in a Cause Map, a form of root cause analysis which provides a visual “map” of cause-and-effect relationships.  We begin by determining the impacts to the goals resulting from this incident.  The safety goal was impacted due to the large number of people who were injured.  (No fatalities have been reported as a result of the crash.)   The customer service goal was impacted because the ferry slammed into a pier (nobody expects that on their morning commute!).  The ferry was damaged, impacting the property goal.  Presumably the ferry will be out of service for some time, impacting the production goal, and will require repairs, impacting the labor goal.  Any time required for the response can also be considered an impact to the labor goal.

A Cause Map can begin as simply as beginning with an impacted goal and asking a couple of why questions.  In this case, the safety goal is impacted by the injuries, which were caused by the ferry striking the pier.  More detail can be added to the Cause Map by asking more “Why” questions.

In this case, it’s not clear what caused the crash, though drug or alcohol use by the captain has been ruled out.  There have been some recent complaints about maneuverability due to a recent overhaul replacing the engine and propulsion system but it’s not clear if this played a role in the crash.  It’s also unclear why the ship was traveling at 14 knots when it was about to dock.  Because the ship was about to dock, people had gotten up from their seats and were standing in hallways and on or near stairways, increasing the rate of injury.  It does not appear that there are any regulations requiring commuters to remain seated until the ferry has stopped moving.

The ferry company, as well as the appropriate transportation authorities, will continue their investigations to determine the causes of the ferry incident.  Once they do, they will provide recommendations or requirements to ensure a safer morning commute.

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

Root Cause Analysis - Incident Investigation

Shattering Glass Cookware

By Kim Smiley

Did you know that glass cookware comes with directions?  Many consumers aren’t aware of that fact or know that there is a risk of their trusty cookware shattering if the directions aren’t followed.

This issue can be analyzed by building a Cause Map, a visual root cause analysis.  To begin the Cause Mapping process, an Outline is filled in with the basic background information.  The impact to the goals is also listed in the Outline.  In this example, the safety goal is impacted because there is a possibility of injury if glass cookware shatters.  The schedule goal is also impacted because of the possibility of messes and ruined meals.  This issue has also generated some negative publicity so it is also an impact to the consumer service goal.  The next step is to ask “why” questions to determine what things contributed to the issue.  These causes are then added to the Cause Map to visually show the cause-and-effect relationships between them.

In this example, the glass cookware explodes because it is subjected to temperature swings and it isn’t able to withstand the change in temperature.   Modern glass cookware isn’t as resilient to temperature changes because it is made of a different material.  Starting in the 1980s, glass cookware started to be manufactured using soda lime silicate glass.  Originally, glass cookware was made with borosilicate glass, which is significantly more resilient to temperature changes.  The change occurred because soda lime silicate is cheaper, more resilient to impacts and better for the environment.

Many consumers aren’t aware that modern glass cookware is different from what they may have grown up using.  As a result, consumers may not be following the new directions and this may cause the cookware to explode.  Many consumers may not even be aware that glass cookware comes with directions.  The directions can be found on the manufactures’ websites if the original packaging was tossed.

A recent article in the American Ceramic Society Bulletin that looked into the issue found that modern glassware is far less resilient to temperature changes and concluded that the margin of safety is borderline.  Consumer Reports also looked into the issue in 2009 with a dramatic video showing shattering cookware.  Consumer Reports warned people to carefully read safety warnings.  Manufacturers of the products stand by their products and are fighting to have the American Ceramic article retracted.  Visit the Pyrex and Anchor Hocking’s website for more information.

If you would like to report an incident of shattering cookware, please contact the Consumer Product Safety Commission at 800-638-2772 or info@cpsc.gov.

Root Cause Analysis - Incident Investigation

The Dangers of Distracted Walking

By Kim Smiley

By now, most of us have heard about the dangers of distracted driving and many states have laws restricting the use of cellphones while driving.  But did you know that walking while distracted is also a potentially dangerous habit?  Researchers observed people crossing the street at busy intersections and determined that people using cellphones or listening to music were significantly more likely to do something risky.  More study needs to be done to understand exactly how distracted walking might be contributing to actual accidents, but it is known that the number of pedestrians killed and injured last year increased from 2010.

This issue can be analyzed by building a Cause Map, a visual, intuitive method for performing a root cause analysis.  The first step in building a Cause Map is to complete an Outline that lists all the basic information about an issue.  The bottom portion of the Outline should also be filled in with how the issue impacts the overall goals.  In this example, there was an increase in pedestrians’ deaths which is obviously an impact to the safety goal and there would be more traffic disruptions because there are more pedestrian accidents occurring.  The next step is to ask “why” questions to determine the causes that contributed to an issue.  The causes are then visually laid out on the Cause Map to show cause-and-effect relationships between them.  Click on “Download PDF” above to view an Outline and high level Cause Map of this issue.

Starting with the safety goal, the Cause Map shows that the number of pedestrians killed has occurred because of the increase in pedestrian accidents.   More research is needed to determine exactly why the number of pedestrian accidents is increasing, but there are a couple of likely causes that should be evaluated.  Based on the evidence that distracted pedestrians act in a risky way, such as not looking  both ways and crossing slower, it’s likely that is a contributing cause.  Use of cellphones, both to talk and text, and the use of headphones is becoming increasinglycommon in our culture so it would be worth researching if this has in fact contributed to increase in pedestrian accidents.  Since it still requires research to validate this cause, it is listed on the Cause Map, but a “?” is included to show that it haven’t been confirmed.  As more information is available, the Cause Map can be updated to reflect any new information.

Some solutions to this problem have already been proposed such as laws restricting cellphone use while walking similar to the distracted driving laws and public awareness campaigns since this issue hasn’t been highly publicized.  The report by the researchers who observed pedestrian habits can be viewed here.

Root Cause Analysis - Incident Investigation

112 Killed in Garment Factory Fire in Bangladesh

By Kim Smiley

At least 112 were killed in a fire at a garment factory in Bangladesh on November 25, 2012. Officials are still investigating what caused the fire, but many disturbing facts about the disaster have already come to light.

This fire can be analyzed by building a Cause Map, a visual root cause analysis.  When constructing a Cause Map, the first step is to fill in an Outline that lays out the basic facts of the incident.  The impacts to the goal are also listed in the Outline and are used as the first box in the Cause Map.  The Cause Map visually lays out the different things that contributed to an issue and shows the cause-and-effect relationship between the different causes.  In this example, the safety goal was the focus because of the number of lives lost.

So many lives were lost because people were working in the garment factory, there was a fire in the factory, workers were unable to quickly leave the factory and the fire burned for a long time.  People were working in a garment factory because this type of factory work is very common in Bangladesh.  Bangladesh is the world’s second largest producer of garments and work in the industry is one of the main sources of stable income available.  About a third of the population of Bangladesh lives in extreme poverty.  Many of the garment workers are also women, who have limited options for employment.   Investigators have not determined what started the fire, but some government officials have speculated that it may have been arson or sabotage.  Workers were unable to get out of the factory quickly because there was only one exit and the stairways were partially blocked by piles of garments.  There were no emergency exits or fire escapes.  The fire burned all night because it was difficult for fire fighters to reach the factory because it wasn’t easily accessible by vehicles.

As sad as this story is, it was nearly a much worst tale.  It was after normal working hours and many workers had already left the factory.  About 1,500 workers were employed at the factory, but only 600 workers remained working overtime.

The factory produced garments for Western companies such as Disney, Sears and Wal-Mart.  It is not clear if companies were aware that their products were being produced in dangerous conditions and there is some confusion with the use of subcontractors, but this fire raises difficult questions. What responsibility do companies have to the workers producing their clothing?  Thousands of garment workers have protested demanding justice for those killed.  This issue is farther complicated by the fact that some workers are grateful for the work and willing to work in substandard conditions because it’s better than the alternatives.

This issue is also reminiscent of a fire that killed 146 garment workers in 1911 in New York City.   The public outrage following the 146 deaths helped lead to many improvements in worker safety in the United States.  Click here to view a previous blog on this incident.

Root Cause Analysis - Incident Investigation

Does Turkey Really Make you Sleepy?

By Kim Smiley

Every year around this time, Americans start thinking about turkey and that sleepy feeling that hits after a Thanksgiving feast.  It has been common to blame the bird for the post feast drowsiness, but is the idea that turkey causes sleepiness true?

This issue, just like any big engineering problem, can be analyzed by building a Cause Map.  A Cause Map is an intuitive, visual format for performing a root cause analysis.  To build a Cause Map, “why” questions are asked to understand the cause-and-effect relationships between the different causes that contribute to an issue.  One cause in this example is the  fact that turkey is typically eaten at a tradition American Thanksgiving feast.  The rumor that it causes sleepiness likely came from the fact that turkey contains tryptophan, an essential amino acid that is found in protein.  Tryptophan is a natural sedative because it used to help the body produce the B-vitamin niacin, which in turn is used to make serotonin.  The body then uses serotonin to make melatonin which helps regulate sleep cycles.  Higher melatonin levels can make a person feel sleepier.

If you stopped the investigation at this point, it might look like turkey is in fact responsible for that post-Thanksgiving nap, but there is more to the story.  The first important thing to note is that turkey doesn’t really contain that much tryptophan compared to other foods.  Turkey actually has less than chicken, which Americans regularly consume without the need for a nap.  Tryptophan is also much more potent when eaten on an empty stomach, which is probably not the case on Thanksgiving Day.

The conclusion is that you can’t blame the bird.  It’s a myth that turkey causes more sleepiness than other foods.  If you feel sleepy after feasting for Thanksgiving it probably has more to do with the work to prepare the meal and amount of food consumed than the properties of the turkey.  But please don’t let this conclusion ruin your fun; feel free to nap the afternoon away anyway.

Happy Thanksgiving from ThinkReliability.  We hope you have many things to be thankful for this year.

Root Cause Analysis - Incident Investigation

Voting Issues in the 2012 Election

By Kim Smiley

Prior to the election on November 6, 2012, some reporters were predicting that the results of the presidential election, which was expected to be nail biter, may not be known for weeks . While this was obviously not the case, there were a few real  hiccups in the voting process.

The voting issues of the 2012 election can be analyzed by building a Cause Map, an intuitive, visual format for performing a root cause analysis.  The first step of the Cause Mapping process is to create an Outline that lays out the basic information of an issue and also lists the impact to the overall organizational goals.  In this example, the general public is considered the “customer” and the voting issues were an impact to the customer service goal since anything that makes it difficult for eligible voters to cast a ballot means the government is not providing adequate customer service to the public.

The next step is to ask “why” questions to understand the different causes that contributed to the problem.  Why were there issues voting?  Part of what made this specific election difficult was the aftermath of Hurricane Sandy.  Areas in the northeast were still without power.  Temporary polling locations had to be established and the change in the normal process was confusing to voters.  Just providing information to voters was complicated because many homes were still without power or damaged and some residents were displaced.

There was also confusion over changes to voter laws prior to the election.  The most publicized example of this is the voter identification laws passed in Pennsylvania.  A law was passed in Pennsylvania that required all voters to show an official form of photo identification, but the law was challenged in court.  Advocates of the law say that it will prevent voter fraud.  Opponents of the law say that it will prevent eligible voters from being able to cast ballots because not all voters have photo identification, a particular issue for the elderly, poor and minorities.  A judge ruled that the law would not apply to the election because voters didn’t have enough time to acquire their photo identification.  This new law and subsequent ruling confused some poll workers and there have been cases reported where voters were turned away for not having identification when it was not yet required.

There were also very long lines reported at some polling locations.  Some voters in Virginia and Texas waited four hours to vote.  This was caused in part because this was a presidential election and predicted to be very close so there was higher than normal voter turnout.  Long lines tend to happen near the end of the day after the traditional workday ends.  Some polling locations also had problems that slowed the process like broken voting machines or staff that didn’t show up.

Luckily, the voting issues didn’t delay the election results and any voters that were mistakenly turned away because of new laws or unable to vote because of the impacts of Sandy would not have changed the overall result of the election.  But officials could certainly use the lessons learned from the 2012 election to help ensure a smoother process for the next presidential election.

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

Rogue Ocean Fertilization Experiment Done

By Kim Smiley

An entrepreneur created a massive bloom of plankton after he dumped a hundred tons of iron dust into the Pacific Ocean off western Canada last June.  This action has sparked outrage because an individual manipulated the environment without government approval or scientific oversight.

A Cause Map, a visual format for performing a root cause analysis, can be built to analyze this issue.  The first step in building a Cause Map is to determine how the issue impacts the overall goals.  The next step is to ask “why” questions and the answers are then organized into cause-and-effect relationships so that all factors that contributed to a problem are laid out in an intuitive format.  In this example, impacts to several goals are worth considering.

The first issue is that nobody knows exactly how the environment will respond to this much iron being put into the ocean.  The environmental impacts may well turn out to be minimal, but this is by far the largest experiment of this type done to date so nobody really knows how big the impact will be.  The experiment is also particularly worrisome because there wasn’t adequate scientific oversight or approvals for it.  The man conducting the experiment was an entrepreneur hoping to make money.  A local tribe hired the entrepreneur to fertilize the ocean with iron in a bid to increase the local salmon population by increasing their food supply.  Adding iron to the ocean can create a rapid increase in the phytoplankton population, which are the base of the aquatic food chain, because iron is often the limiting nutrient for phytoplankton growth.  Iron is necessary for photosynthesis and thus phytoplankton growth.  But iron is also highly insoluble in sea water so large areas of the ocean have limited iron supplies.

The entrepreneur also hoped to find a way to cash in on carbon offset credits because phytoplankton blooms may be a way to sequester carbon and improve greenhouse gas numbers in the environment.  This may work because phytoplankton absorb carbon dioxide during their life and when they die they sink into the ocean, taking the carbon dioxide with them and removing it from the atmosphere.

The second issue is that there are known risks associated with large blooms of phytoplankton.  They can negatively affect the other aquatic life in the region because large blooms can deplete the ocean of oxygen.  This occurs because the populations of other microorganisms will increase since the increase in phytoplankton provides a larger food supply.  Some of these other microorganisms absorb oxygen so more of them means less oxygen for other aquatic life. Phytoplankton live near the surface, but they sink as they die so a bloom will impact the food supply and oxygen levels throughout the entire depth of the ocean.

A final goal worth considering is the impact this has on public opinion.  Iron fertilization is a contentious issue to begin with because many people are opposed to purposefully manipulating the environment.  When somebody dumps tons of iron into the ocean without solid scientific involvement it understandablely outrages the public. The negative press will make it harder for any legitimate scientific research being done in this field.

This issue has been covered by The New York Times , The New Yorker  and NBC news. Click on any of these links to learn more about this issue.  Click on “Download PDF” above to view a high level Cause Map.

 

Root Cause Analysis - Incident Investigation

The Dangerous Combination of Hot Cars and Children

By Kim Smiley

Every summer, the news covers heartbreaking stories of children who die after being inadvertently left inside a vehicle.  Since 1998, 527 children have died from heat stroke from being exposed to high temperatures inside a vehicle.  One of the most tragic elements of these stories is that these deaths are preventable.

This issue can be analyzed by building a Cause Map, a visual root cause analysis that intuitively lays out all the causes that contributed to the problem. The first step in building a Cause Map is to determine how the issue affects the overall goals.  In this example, the safety goal is the obvious focus since there have been hundreds of deaths.  The next step is to ask “why” questions and add the answers to the Cause Map.  Why have 527 children died?  They died of heat stroke because they were left inside a car and the interior of the car was hot.  Children also overheat quicker than adults because their thermoregulatory system isn’t as efficient.

The children were left inside the car because they were inadvertently forgotten, a caregiver intentionally left them inside or the children managed to get inside the cars themselves.  There are a number of reasons that a caregiver could forget a small child. The most frightening thing about these incidents is that it can happen to well intentioned, loving parents who simply make a terrible mistake.  These incidents tend to occur most often when there is a change of routine, such as a different parent than normal doing the daycare drop off.  It certainly doesn’t help that many parents and caregivers of young children are tired and potentially sleep deprived. The driver may also not be able to see a small child because many states require backward facing car seats in the back seat.   In the cases where a caregiver intentionally leaves a child and no harm was intended, it’s safe to assume that they didn’t understand the danger.  There are also cases where a child enters a car and becomes trapped inside.  In those examples, the vehicle was most likely unlocked and the caregiver didn’t realize the child was playing in the vehicle.

Vehicles are  especially dangerous because they heat up very quickly to dangerous levels.  A car is an enclosed space with a lot of windows to let in sunlight, making it an ideal situation for temperatures to increase.  Even relatively mild days can result in hot temperatures inside a car.  The temperature inside a car can raise about 40 degrees even when the ambient temperatures are in the 70s, meaning the inside of a car can be over 110 degrees on a fairly cool day.

There are a number of gadgets people have invented to help prevent children from being inadvertently forgotten in a car, but their effectiveness is debated.  The simplest way to prevent this from happening is very low tech; put your purse, shoe or anything that you must have in the backseat.  Another suggestion is to keep a large stuffed animal in the car seat and then move it up to the front passenger seat while the car seat is occupied so that you have a visual reminder of your precious cargo.  The most important thing is to be aware of this deadly problem and have a plan to prevent it if you ever drive around children, especially those strapped into car seats.

Root Cause Analysis - Incident Investigation

Why Giant Pandas are Endangered

By Kim Smiley

Panda breeding programs continue to struggle, a fact unfortunately highlighted by the recent death of a week old panda cub at the National Zoo on September 23, 2012.  Breeding programs are an important part of the panda conservation effort since the adored animals are endangered with only an estimated 1,600 remaining in the wild and about 300 in captivity.

The factors that contributed to pandas becoming endangered can be analyzed by building a Cause Map, a visual root cause analysis.  A Cause Map is an intuitive way to show the cause-and-effect relationships between the different causes that contribute to an issue. In this example, a good starting point is to ask why pandas are endangered.  This happened because there aren’t enough viable habitats, pandas have a low birth rate and panda cubs have a high mortality rate.

The panda habitat has significantly decreased because the bamboo forests are being cleared as the region becomes more industrialized.  Pandas also need a large habitat.   They are large animals who consume mostly bamboo so a lot of it is needed to sustain them.  The average panda can consume 20 to 30 pounds of bamboo shoots each day. They are also solitary, territorial creatures and do not like to live close to each other.

Pandas also have a notoriously low birth rate, in the wild and especially in captivity.  Female pandas are only fertile once a year for a very short window, about 36 hours.  In the wild, pandas have to find a mate (that they don’t typically live near) while fertile to produce a cub for the year.  Pandas in captivity struggle with conception even when they share an enclosure with a potential mate because they seem to lose interest in “natural breeding”.  The recent cub born at the National Zoo was the product of artificial insemination.  If a panda does manage to conceive, she will still only raise a single cub per year.  Most of the time only a single baby is born, but even if twins occur only one usually survives.

Panda cubs that are born also face a high mortality rate.  Twenty-five percent of panda cubs born in the US don’t survive their first year and the numbers are lower in the Chinese breeding centers.  This occurs because panda cubs are born very small, about the size of a stick of butter, and immature.  The newborns are helpless, pink and blind and require a lot of care taking to survive.  There is also the heart breaking chance that a mother panda can inadvertently injure her cub because she is much larger than her newborn and needs to handle it frequently to nurse it and care for it.

At this point, no captive panda has successfully been reintroduced into the wild and it’s unlikely that they will be in the foreseeable future.  Only time will tell if conservation efforts are successful for the giant pandas.

To view a high level Cause Map of this issue, click “Download PDF” above.