Root Cause Analysis - Incident Investigation

The Dreamliner’s Battery Nightmare

By Kim Smiley

On January 16, 2013, the Federal Aviation Administration issued an emergency directive grounding all Boeing 787 Dreamliners operated by United States carriers during the investigation into two recent battery fires.  This emergency grounding is an unusually extreme step, especially given that the Dreamliner is a new plane with only six operated by US carriers at this time.

This issue can be analyzed by building a Cause Map, an intuitive, visual format for performing a root cause analysis.  A Cause Map is built by determining how the issue affects the goals of an organization and then asking “why” questions to find the causes that contributed to the problem.  In this example, the schedule goal is impacted because the Dreamliners have been grounded.  Why?  The Dreamliners were grounded because there is a known fire risk because there were two battery fires onboard these airplanes nine days apart.  The fact that the Dreamliner is the first major airliner to extensively use lithium-ion batteries and that fires in these batteries are particularly dangerous also contribute to the problem.   Lithium-ion batteries were used because they are lighter than other batteries and lighter planes use less fuel.  Fires in lithium-ion batteries are dangerous because they are difficult to extinguish because oxygen is released as they burn, which feeds the fire.

Several other goals are also worth considering like the customer service goal which is impacted by the negative publicity generated by this issue and the safety goal because there is a potential for injuries.   The economic impact of this issue could also be very significant since each Dreamliner costs $200 million and there are 800 planes on order in addition to about 50 that were already in service that may need to be repaired.

The battery fires are still being investigated but the cause isn’t known yet.  It may be an issue with manufacturing or the design itself.  What is known is that the Dreamliner is a brand new design that incorporates many new elements such as mostly electrical flight systems, an airframe that uses composite materials and the use of the lithium-ion batteries themselves.  The design process was also different from previous Boeing designs with much of the work outsourced to a network of global suppliers and very tight deadlines.

As more information becomes available, the Cause Map can easily be expanded to incorporate it.  To view a high level Cause Map of this issue, click on “Download PDF” above.

Root Cause Analysis - Incident Investigation

Beijing’s “Airpocalypse”

By Kim Smiley

Beijing’s air pollution was at levels considered hazardous to human health for nearly a week during mid-January 2013.  During this event, colorfully dubbed the “airpocalypse”, pollution levels peaked at 755 as measured by the Air Quality Index (AQI).  This value is considered “Beyond Index” because it is well above the 500 which is considered the maximum AQI value.  Any AQI value over 300 is considered hazardous.

This issue can be analyzed by building a Cause Map, an intuitive format for performing a visual root cause analysis.  The first step in building a Cause Map is to fill in an outline with the basic background information.  The impacts to the organizational goals are also listed in the Outline.  In this example, the safety goal is impacted because people are reporting respiratory issues and there is a possibility of long term health problems because millions were exposed to hazardous air pollution.  The customer service goal has also been impacted because of the negatively publicity that the air pollution issues have generated.  The impacts to the goals are used to build the Cause Map by asking “why” questions.

Why were millions exposed to hazardous air pollution?  This happened because there was air pollution produced in and around Beijing and the pollution was trapped in the city.  A number of sources contributed to the air pollution.  There are many coal burning factories in the area and the amount of coal burnt as a heat source has increased recently because of unusually cold weather.  The number of cars in the city is also increasing at an amazing rate, with thousands more added to the city traffic daily.   There is also a lot of construction in the city needed to meet the demands of such a large population. The pollution was trapped in the city because of the city’s geography and the weather.  Beijing sits on a plain and is flanked by hills.  If the wind doesn’t blow in the right direction to push the  pollution out to sea, it will be trapped by the hills and blanket the city, which is what happened in this case.

The final step in the Cause Mapping process is to develop and implement  solutions to prevent the same thing from recurring.  The Chinese government did take several steps to try to mitigate the  immediate problem with the air pollution by limiting the use of cars and temporarily shutting down some factories.  The pollution finally cleared up as the wind began to blow, but continued efforts will be needed to prevent similar issues in the future.

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

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

Over 60,000 Vehicles Recalled Due to Steering Column Defects

By Kim Smiley

General Motors Co has announced a recall of over 69,000 full-size trucks and vans because of steering column defects that may allow a parked car to roll away.  Only about 1 in 1,000 of the recalled vehicles is expected to have the defect.

This issue can be analyzed by building a Cause Map, or visual root cause analysis.    A Cause Map is an intuitive way to visually show the cause-and-effect relationships between the many causes that contribute to an issue.  In this example, the recall was announced because there are a large number of vehicles that need to be inspected.  The inspections are necessary because some vehicle need to have the steering columns replaced.  The replacements are necessary because a small percentage of vehicles have defective steering columns that may allow a parked car to roll.

Investigation into the steering column defects found that there were two separate issues causing similar problems.  There is a possibility that the column lock module assembly might malfunction because of a manufacturing issue with a component.  Investigators also found that some shift cables had been fractured because of mishandling.  Both issues resulted in the same potential safety issues.  If the steering column defects are present a parked car could roll away because it may be possible to shift from park when the key is removed or in “off” position, shift from park with application of brake pedal with key in “off” position, or to turn the key to the “off” position and remove while not in park.  To view a high level Cause Map of this issue which includes all these causes, click on “Download PDF” above.

Once the Cause Map is built, the final step in the process is to determine a solution to prevent recurrence.  Once the problems were identified the solution was fairly straightforward.  The recall was initiated to inspect all vehicles potentially affected by these issues and replace the steering column if a defect is found.

A recall is never a good thing for a company, but one silver lining in this incident is that the company identified the problem during an audit before receiving any reports of issues.  There have been no reports of accidents or injuries caused by these steering column defects.  The majority of the vehicles are also believed to be either in transit to dealers or sitting on dealer lots so a limited number of customers should be impacted by the recall.

 

 

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

40 Percent of Food in America is Wasted

By Kim Smiley

A report by the Natural Resources Defense Council found that a shocking 40 percent of food in America is wasted.  This means that a huge amount of resources are being used to produce food that is never eaten.  Even worse, this food is left to rot in landfills, which produces the greenhouse gas methane.   Landfills are responsible for 34 percent of all methane emissions in thee United States.

This issue can be analyzed by building a Cause Map, a visual format for performing a root cause analysis.  The first step in Cause Mapping is to fill in an Outline with all the basic information and determine the goals that are impacted.  In this example, the environmental goal is impacted because of the increase of greenhouse gases in the atmosphere and the production goal is impacted because $165 billion of food wasted in United States this year.  Once the impacts are determined, the Cause Map is built by asking “why” questions and adding the answers until the cause-and-effect relationships between all the factors that contributed to an issue are clear.

Starting with the environmental goal, the next step is to ask “why” greenhouse gases are being produced.  Methane, a greenhouse gas, is being produced by the tons of food rotting in landfills.  Tons of food is in landfills because 40 percent of the food in the United States is wasted and that is generally where it ends up.  There is such a large amount of  food waste because there is waste at every step of the food chain and there is little motivation to stop wasting food.  There isn’t sufficient motivation to curb the waste because food is relatively cheap and plentiful in this country.  People are also unaware of the scope of the problem and don’t realize that rotting food is a significant environmental issue.

There are a number of reasons that food is wasted at the different steps in the food chain.  About seven percent of food in the United States never even leaves the field.  A number of things cause this, such as more crops being planted than needed to hedge against bad weather or disease, fluctuating food prices making the harvest prohibitively expensive, and produce that doesn’t meet the size and color standards.   There is a lot of waste post-harvest because edible food is culled that doesn’t always meet the high aesthetic standards of this country.  Grocery stores’ practices also result in a lot of wasted food because they overstock products so they don’t look empty and toss a lot of food that is near or at its sell by dates.  Food services and restaurants also contribute to food waste.  It’s estimated that seventeen percent of the food is left on plates by diners, partly because of the ever increasing portion sizes.  Finally, it’s worth note how much food is wasted in the average American household.  It’s estimated that families throw out between 14 and 25 percent of all food and beverages they purchase.

There will always be some waste associated with food production, but there are simple ways to improve.  Better meal planning, eating more leftovers, lower aesthetic standards for produce, and better understanding of sell by dates by consumers would all help.

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

Gas Explosion Rocks Springfield, Massachusetts

By Kim Smiley

On Friday, November 23, 2012, a massive gas explosion rocked downtown Springfield, Massachusetts.  No one was killed because the area had been evacuated while a suspected gas leak was investigated, but 20 people were injured and many buildings were damaged.

This incident can be analyzed by building a Cause Map, an intuitive, visual way to perform a root cause analysis.  The first step when creating a Cause Map is to document the basic information in an Outline and determine how the goals were impacted.  In this example, the safety goal was impacted because there were injuries as well as the possibility for fatalities.  The material goal was impacted because 42 buildings were damaged, including three that were immediately condemned.  The schedule goal is also impacted because many businesses in the area closed during the necessary inspections and repairs.

Once the impacts to the goals are determined, the Cause Map is built by asking “why” questions.   In this incident, buildings were damaged because there was a major gas explosion.  This occurred because there was oxygen, a spark and a natural gas leak.  Investigators have not been able to determine the source of the spark and may not be able to answer that question due to the extent of the damage.  The gas company has released information on what caused the gas leak.

Someone had called in to report a gas smell in the area and the gas company had sent workers out to investigate and evacuated the area at some point during the process.   The explosion occurred because a high pressure gas pipeline was inadvertently punctured by a worker who was investigating the reported gas smell.  He was using a long metal tool to probe the ground looking for gas underground when the tool accidently hit the pipeline, creating a gas leak.  This occurred because the worker wasn’t aware of the location of the pipeline.  He was using markings on the sidewalk that indicated the location of the pipeline, but the markings didn’t show the correct location.   He moved to what he thought was a safe distant from the location of the pipeline, inserted the tool into the ground and struck the incorrectly marked pipeline.  The gas company has stated that the worker was following standard procedure.

It’s also worth noting that none of the injuries were life threatening.  If the area hadn’t been evacuated at the time of the explosion there would likely have been many fatalities.  At least one local business that would have been opened at the time of the explosion was completely leveled.

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

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.