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A Lesson in Miscommunication: Valentine’s Day Blues

By Renata Martinez with contributions from the staff of ThinkReliability

I better preface this blog with a few comments….

It’s  not your average blog.  As a facilitator, I deal with a lot of serious problems on a daily basis.  Believe it or not I get these incidents stuck in my head and spend a lot of time thinking how I can better explain some lessons I’ve learned as a facilitator.  The goal of this blog is to offer a little perspective into an incident where “miscommunication” is identified and I wanted to use something you could probably relate to. Have you ever been in an argument with a significant other?  Maybe you didn’t see eye-to-eye on something (a Netflix option perhaps), or someone did something unexpected, or someone said something they didn’t mean (“Feel free to go golfing today; you don’t need to start on that to-do list”).

I also want to preface this blog by stating I am not a relationship counselor and I do not have a perfect relationship because of Cause Mapping.  However, I will say that Cause Mapping has helped me gain an understanding of a whole new perspective – his.

Without further ado, let me set the stage.  I have to take you back a bit.  Let me take you back to my Sophomore year in college. *enters dream state*

Valentine’s Day:  I hate it.  I’ve always thought it was a commercialized endorsement to express love.   The seemingly endless aisles in store after store of red and white hearts, chocolates, cards, teddy bears – gross.  …and then I met my future husband.  I was so head over heels for this guy, you would have thought I was 12 (but I was 20).  So when Valentine’s Day came around our new love I was actually excited.  The thought crept into my mind that I could be wow-ed this time; this could be it, I could learn to love Valentine’s Day.  I had the opportunity to relive every Nicolas Sparks novel ever written.  Expectations were set.

Leading up to the 14th, there was a conversation that took place that would ensure I will always despise the day…. I was asked what I wanted.  My mind quickly played one romantic scene after another but that’s not what came out of my mouth.  Instead I replied, “nothing.”  Well, being the literal person he is, he took this and ran with it – he got me nothing.  I was so disappointed because when I said “nothing”, OF COURSE I DIDN’T MEAN IT.   “Nothing” was a clear translation for: you figure it out, you surprise me with some immaculate plan. I didn’t want to spell out what I wanted; I wanted to be the cool, low maintenance, laid back girlfriend. I don’t think he was too impressed with my “cool, laid back attitude” when I came to the realization that I didn’t get anything for Valentine’s day – the first time I actually wanted something.

So that’s one branch of the Cause Map: why did I not ask for anything on Valentine’s Day?

At this same point of the Cause Map, it splits with an AND statement.  He also had to assume that I meant “nothing” when he asked.  In my mind it’s so obvious…it’s like when I haven’t talked or looked at you all day and when you ask “What’s wrong?” and I say “Nothing.”  I don’t mean it; it’s just an impulse reaction (and admittedly makes understanding me very difficult).  But since this was his first experience with me and this kind of situation, he didn’t think more about it.  He didn’t realize that I may actually want something.

I know this is a basic example of understanding both perspectives but it comes up a lot on investigations.  Understanding how people both give and interpret instructions/ directions is very important with regards to understanding solutions.  For instance, I will never say that I want “nothing” for a holiday ever again.  My new minimum “requirement” is a card. I really like cards.  And since I’ve got your attention, I’ll give you a little hint about present-giving: the presents should always be wrapped…in gift wrap (the bag from the store does not count).

Looking at solutions for him: he no longer takes the answer “nothing” literally.  Based on this experience, he now understands that I may not mean it.  So, the solutions identified will help him, but if we were looking at a different employee (or boyfriend in this example) – how do we ensure it doesn’t happen to them? This is where we need to consider others who may learn from this (not just those directly affected in this incident).  And this is why sharing lessons learned is so important.

By identifying both perspectives on the Cause Map, we can learn a lot about why an incident occurred (and what had to happen).  This yields more effective solutions that will prevent reoccurrence.  …after all: happy wife, happy life . . . right?!

To view both perspectives on a Cause Map, click on “Download PDF” above.

 

Root Cause Analysis - Incident Investigation

Failure of the Nipigon River Bridge

By Kim Smiley

On the afternoon of January 10, 2016, the deck of the Nipigon River Bridge in Ontario unexpectedly shifted up about 2 feet, closing the bridge to all vehicle traffic for about a day.  After an inspection by government officials and the addition of 100 large cement blocks to lower the bridge deck, one lane was reopened to traffic, with the exception of oversized trucks. Heavier trucks are required to detour around the bridge with the main alternative route requiring crossing into the United States.  This failure is still being investigated and it isn’t known yet when it will be safe to open all lanes on the bridge.

More information is needed to understand all the details that led to this failure, but an initial Cause Map, a visual root cause analysis, can be built to illustrate what is currently known. The first step in the Cause Mapping process is to fill in the Outline to document the basic background information (the what, when and where) and the impacts to the organization’s goals resulting from the issue.  For this example, the bridge was damaged and significant resources will be needed to investigate the failure and repair the bridge.  The closure of the bridge, and subsequently having only a single open lane, is also having a sizable impact on transportation of both people and goods in the area.  It is estimated that about $100 million worth of goods are moved over the bridge daily and there are limited alternative routes.

Once the Outline is completed, the Cause Map is built by asking “why” questions and visually laying out the cause-and-effect relationships.  Why did the deck of the bridge shift up?  Investigators still don’t have the whole answer. The Nipigon River Bridge is a cable stayed bridge and bolts holding the bridge cables failed, resulting in the deck of the bridge being pulled up at an expansion joint.  Two independent testing facilities, National Research Council of Canada in Ottawa and Surface Science Western at Western University, are conducting tests to determine the cause of the bolt failures, but no information has been released at this time.

The Nipigon River Bridge is a new bridge that has only been open since November 29, 2015. Some hard questions about the adequacy of the bridge design have been asked because the failure occurred so soon after construction.  Officials have stated that the bridge design meets all applicable standards, but investigators will review the design and structure during the investigation to ensure it is safe.  Ontario winters can be harsh and investigators are going to look into whether cold temperatures and/or wind played a role in the failure.  Eyewitnesses have reported a large gust of wind just prior to the bolt failure.  Investigators will determine what role the wind played.

The Cause Map can easily be expanded to incorporate new information as it becomes available. Once the Cause Map is completed, the final step in the Cause Mapping process is to develop solutions to prevent a similar problem from recurring.  In this example, adding the concrete blocks as counter weights allowed one lane of the bridge to be opened in the short term, but clearly a longer-term solution will be needed to repair the bridge and ensure a similar failure does not occur again.

Root Cause Analysis - Incident Investigation

Is Having a Lockout/ Tagout (LOTO) Procedure Enough?

By Staff

The number of possible types of injuries occurring when performing work on energized equipment is impossible to count.  They can range from burns, to electrical shock, to crush injuries, to cuts/lacerations, and beyond.  In an effort to help eliminate some of these injuries, the OSHA standard for Control of Hazardous Energy (29 CFR 1910.147), more commonly known as lockout/tagout (LOTO), went into effect in 1989.  The purpose of the standard is to help companies establish the practices and procedures needed to prevent injury to workers when they are performing maintenance activities to equipment requiring an energy source.  Any company in violation of the standard is subject to a fine.  It is estimated that in 2013, there were approximately $14 million in federal and state fines, and lockout/tagout was the 5th most frequently violated standard in 2015.

However, the REAL goal of the standard is to keep people safe.  So how is the standard violated?  It can happen in many ways, but this blog takes a look at one specific incident to better understand  how it can happen.  This analysis is based on a case study presented in the article “Lockout/Tagout Accident Investigation” from the August 2014 issue of Occupational Health & Safety.

In this incident, several contractors were working on a project involving a particular switchgear.  Many of these contractors had performed lockout/tagout for the switchgear box related to the projects that they were working on.  After the work began, a worker from a different contractor was asked to clean out part of the switchgear.  Unfortunately, an arc flash occurred when he reached in the switchgear, resulting in burns to his hand and a blow-out injury to his knee.  Fortunately, the employee survived, recovered, and was able to return to his normal life.

A Cause Map can be built to analyze this issue.  The first step in Cause Mapping is to determine how the incident impacted the overall goals.  For this incident, the safety goal was the most obviously impacted goal due to the injuries that the worker sustained.  The goal is always for employees to leave the workplace in the same health in which they arrived.  Additionally, the regulatory goal was impacted since the injuries were severe enough that they were classified as recordable.

The Cause Map is a visual representation of the cause-and-effect relationships that contributed to the incident.  Starting with the impacted safety goal, ‘why’ questions can be asked to identify the key factors that caused the problem.  In this case, the injuries were caused by the fact that an arc flash occurred when the worker reached into the switchgear and he was not wearing personal protective equipment.  The worker was probably not wearing PPE because he thought that the switchgear was de-energized, and this was an effect of the fact that there were locks and tags already on the switchgear.  The arc flash was a result of the fact that the circuit breaker was energized when the worker reached in to clean it.  The circuit breaker was energized because of three factors: a different contractor had put it back in service the night before, the circuit was not tested by the worker, and the worker didn’t do his own lockout procedure.  Each of these problems can be further analyzed to reveal problems with communication, adding the task at the last minute and not including every task in a job safety analysis.

For this situation, and many like it, eliminating a cause anywhere on the map could have minimized the risk of the incident occurring.  For example, had the worker taken the time to put on protective equipment or test the circuit breaker, he might not have been injured.  Similarly, had the other contractors taken the time to update their locks/tags and ensure that they had communicated that the circuit had been reenergized to all interested parties, the worker might not have been injured.  This example demonstrates that having a lockout/tagout procedure is the first step in avoiding injuries.  Ensuring that the procedure is followed in combination with other safety standards is also important to minimize the risk of injury.

Root Cause Analysis - Incident Investigation

Landslide of construction debris buries town, kills dozens

By ThinkReliability Staff

Shenzhen, China has been growing fast. After a dump site closed in 2013, construction debris from the rapid expansion was being dumped everywhere. In an effort to contain the waste, a former rock quarry was converted to a dump site. Waste at the site reached 100 meters high, despite environmental assessments warning about the potential for erosion. On December 20, 2015, the worries of residents, construction workers and truckers came true when the debris slipped from the quarry, covering 380,000 square meters (or about 60 football fields) with thick soil as much as 4 stories high.

A Cause Map can be built to analyze this issue. One of the steps in the Cause Mapping process is to determine how the issue impacted the overall goals. In this case, the landslide severely impacted multiple goals. Primarily, the safety goal was impacted due to a significant number of deaths. 58 have been confirmed dead, and at least 25 are missing. The environmental goal and customer service goal were impacted due to the significant area covered by construction waste. The regulatory goal is impacted because 11 have been detained as part of an ongoing criminal investigation. The property goal is impacted by the 33 buildings that were destroyed. The labor goal is also impacted, as are more than 10,600 people participating in the rescue effort.

The Cause Map is built by visually laying out the cause-and-effect relationships that contributed to the landslide. Beginning with the impacted goals and asking “Why” questions develops the cause-and-effect relationships. The deaths and missing persons resulted from being buried in construction waste. Additionally, the confusion over the number of missing results from the many unregistered migrants in the rapidly growing area. The area was buried in construction waste when waste spread over a significant area, due to the landslide.

The landslide resulted from soil and debris that was piled 100 meters high, and unstable ground in a quarry. The quarry was repurposed as a waste dump in order to corral waste, which had previously been dumped anywhere after the closure of another dump. Waste and debris was piled so high because of the significant construction debris in the area. There was heavy construction in the area because of the rapid growth, resulting in a lot of debris. Incentives (dumpsite operators make money on each load dumped) encourage a high amount of waste dumping. Illegal dumping also adds to the total.

While an environmental impact report warned of potential erosion, and the workers and truck drivers at the dump registered concerns about the volume of waste, these warnings weren’t heeded. Experts point to multiple recent industrial accidents in China (such as the warehouse fire/ explosion in Tianjin in August, the subject of a previous blog) as evidence of the generally lax enforcement of regulations. Heavy rains contributed to ground instability, as did the height of the debris, and the use of the site as a quarry prior to being a waste dump.

Actions taken in other cities in similar circumstances include charging more for dumping debris in an effort to encourage the reuse of materials and monitoring dump trucks with GPS to minimize illegal dumping. These actions weren’t implemented in Shenzhen prior to the landslide, but this accident may prompt their implementation in the future. Before any of that can happen, Shenzhen has a long way to go cleaning up the construction debris covering the city.

Root Cause Analysis - Incident Investigation

Celebrating with a bit of bubbly? Read this first . . .

By ThinkReliability Staff

What better day than New Year’s Eve to pop open a bottle of champagne (or its non-French sibling, sparkling wine)? Great thought, but turns out there’s a right way to open a bottle of bubbly, and “pop” has nothing to do with it.

Your initial thought may be who cares? What possible difference could it make how I open a bottle? Well, assuming your goal is to celebrate an enjoyable evening with friends, family, or maybe a date, using an improper opening procedure could impact the safety goal, by injuring yourself or others. It can also affect your reputation by failing to impress those with whom you’ve chosen to celebrate (as well as anyone else in the vicinity). The lost champagne is an impact to the property goal, and the potential for clean-up impacts the labor goal (and is clearly not what you want to be spending your New Year’s Eve doing).

A study claims that 900,000 injuries per year result from champagne. Injuries typically result from corks hitting faces, especially eyes. The pressure inside a bottle of champagne can be as high as 90 pounds per square inch, resulting in a cork traveling at speeds of up to 50 miles an hour. Injuries resulting from slips on spilled champagne also fall into this category.

Both spills and flying corks can be prevented by using a proper procedure to open a bottle of champagne. The preparation starts far before the party does. The first step is to ensure that the champagne is cooled properly. This is not only for taste, but also for safety. Another study found that cooling the bottle to 39 degrees F (4 degrees C) reduces the speed at which the cork leaves the bottle. (The cork travels only 3/4 of the speed of that from a room temperature, or 64 degrees F, bottle.)

Once you’re ready to serve the champagne, grab the bottle, glasses, and a kitchen towel. Check to see if there’s a tab on the foil covering the neck. If not, you’ll also need a knife. (One thing you won’t need? A corkscrew.) Remove the foil from the neck, by pulling the tab if one is present or by cutting with a knife, and then peeling it off. From this point until you start pouring, keep the bottle pointed at a 45 degree angle, and away from people, breakable objects, walls and ceilings. Untwist the wire tab, or key, and remove the wire cage, and hold your thumb over the cork. Cover the cork and neck of the bottle with the kitchen towel, and grab both the towel and cork with one hand. With the other hand, gently and slowly twist the bottle until the cork slides out. (This will be not with a pop, but more of a whimper.) Do not shake the bottle!

Hold champagne flutes at an angle and pour champagne in on the side to preserve the bubbles. Repeat as necessary. If you’ll need to leave the location at which you are drinking, please do it as a passenger, or wait until you’ve sobered up. For an average person, that means waiting about an hour for every 5 ounces of wine/ champagne consumed. (The drink size of other kinds of alcohol is defined differently, and your weight will impact the time it takes for alcohol to leave your system.)

If you or someone else forgets these rules and ends up getting hit in or near the eye with a champagne cork, take a trip to the ophthalmologist right away. (Because it’s New Year’s Eve, you may have to hit the emergency room first.) Says ophthalmologist Andrew Iwach, MD, “The good news is that as long as we can see these patients in a timely fashion, then there’s so many things we can do to help these patients preserve their vision.”

To view a visual diagram of the proper champagne-opening procedure, click on “Download PDF” above.

Root Cause Analysis - Incident Investigation

Newly Commissioned USS Milwaukee Breaks Down at Sea

By ThinkReliability Staff

On December 11, 2015, just 20 days after commissioning, the USS Milwaukee completely lost propulsion and had to be towed back to port. This obviously brought up major concerns about the reliability of the ship. Said Senator John McCain (R-Arizona), head of Senate’s Armed Services Committee, “Reporting of a complete loss of propulsion on USS Milwaukee (LCS 5) is deeply alarming, particularly given this ship was commissioned just 20 days ago. U.S. Navy ships are built with redundant systems to enable continued operation in the event of an engineering casualty, which makes this incident very concerning. I expect the Navy to conduct a thorough investigation into the root causes of this failure, hold individuals accountable as appropriate, and keep the Senate Armed Services Committee informed.”

While very little data has been released, we can begin an investigation with the information that is known. The first step of a problem investigation is to define the problem. The “what, when and where” are captured in a problem outline, along with the impacts to the organization’s goals. In this case, the mission goal is impacted due to the complete loss of propulsion of the ship. The schedule/production goal is impacted by the time the ship will spend in the shipyard receiving repairs. (The magnitude and cost of the repairs has not yet been determined.) The property/equipment goal is impacted because metal filings were found throughout both the port and starboard engine systems. Lastly, the labor and time goal is impacted by the need for an investigation and repairs.

The next step of a problem investigation is the analysis. We will perform a visual root cause analysis, or Cause Map. The Cause Map begins with an impacted goal and asking “why” questions to diagram the cause-and-effect relationships that led to the incident. In this case the complete loss of propulsion was caused by the loss of use of the port shaft AND the loss of use of the starboard shaft. The ship has two separate propulsion systems, so in order for the ship to completely lose propulsion, the use of both shafts had to be lost. Because both causes were required, they are joined with an “AND”.

We continue the analysis by continuing to ask “why” questions of each branch. The loss of use of the port shaft occurred when it was locked as a precaution because of an alarm (the exact nature of the alarm was not released). Metal filings were found in the lube oil filter by engineers, though the cause is not known. We will end this line of questioning with a “?” for now, but determining how the metal filings got into the propulsion system will be a primary focus of the investigation. The loss of use of the starboard shaft occurred due to lost lube oil pressure in the combining gear. Metal filings were also found in the starboard lube oil filter. Again, it’s not clear how they got there, but it will be important to determine how the lube oil system of a basically brand new ship was able to obtain a level of contamination that necessitated full system shutdown.

While metal filings in the lube oil system is not a class-wide issue, it’s not the first time this class of ship has had problems. The USS Independence and USS Freedom, the first two ships of the class, suffered galvanic corrosion which caused a crack in the Freedom’s hull. The Freedom also suffered issues with its ship service diesel engines, a corroded cable, and a faulty air compressor.

Once all the causes of the breakdown are determined, engineers will have to determine solutions that will allow the ship to return to full capacity. Additionally, because of the number of problems with the class, the investigation will need to take a good look at the class design and manufacturing practices to see if there are issues that could impact the rest of the class going forward.

To view a one-page downloadable PDF with the beginning investigation, including the problem outline, analysis, and timeline, click “Download PDF” above.

Root Cause Analysis - Incident Investigation

Why New Homes Burn Faster

By Kim Smiley

Screen Shot 2015-12-04 at 11.50.42 AMResearch has shown that new homes burn up to eight times faster than older homes.  What this means is that people have less time to get out of a house when a fire starts – a lot less time.  People living in older homes with traditional furnishings were estimated to have about 17 minutes to safely evacuate a home, but the time decreases to about three minutes in a home built with modern materials and furnished with newer, synthetic furniture.

Modern manufactured wood building materials have a lot of advantages. They are lighter, stronger and cheaper than using traditional wood materials, but these characteristics also mean they burn a lot faster.  Additionally, modern homes typically contain more potential fuel for fires. Many modern furnishings are manufactured using synthetics that contain hydrocarbons, which are a flammable petroleum product.  Furnishings manufactured with synthetic products will burn faster and hotter than traditional furnishings built using wood, cotton and down.  Most modern homes also just simply have more stuff in them that is potential fuel.

Other factors can also make modern homes more dangerous when a fire occurs. Many modern homes are open concept designs as opposed to more compartmentalized traditional designs.  Open spaces in a home can provide more oxygen for a fire to quickly grow.  Additionally, modern energy-efficient windows can help trap heat in a home when a fire starts and can lead to a fire spreading more rapidly. Changes in the way we live and build homes and furnishings have all contributed to modern homes building significantly faster, a potential danger that people need to be aware of so that they can work to keep themselves and their children safe.

The best way to protect yourself and your family is to prevent a fire from occurring in the first place.  Never leave candles burning unattended. Keep all potentially flammable items away from fireplaces and heaters. Don’t leave things on the stove unattended. During the holidays, make sure to keep Christmas trees well watered and away from heat sources and ensure candles are a safe distance from any potentially flammable objects.   These and other basic common sense steps really do prevent fires from occurring.

Of course there is no way to guarantee that a fire will never occur so every house needs working smoke detectors.  It is recommended that they are checked monthly to verify they are functional and that the batteries are changed regularly.  Most fatalities associated with home fires are in homes without working smoke detectors so it really is worth the time and effort to ensure they are kept in good working order.

To view a Cause Map, a visual root cause analysis of this issue, click on “Download PDF” above.

 

Root Cause Analysis - Incident Investigation

High School Open Flame Chemistry Demonstration Ends in Injuries

By Kim Smiley

Six were injured, two seriously, in an accident involving an open flame chemistry demonstration at a high school in Fairfax County, Virginia on October 31, 2015.  At the time of the incident, the teacher was performing a well-known experiment to show the students how different chemical elements can change the color of a flame. According to students present in the classroom, the teacher was in the process of adding more flammable liquid to the experiment when a splash of fire hit students and the teacher.

A Cause Map, or visual root cause analysis, can be used to analyze this incident.  The first step in the Cause Mapping process is to fill in an outline to document all the basic background information for an incident such as time, date, and location.  Additionally, how the incident impacts the organization’s goals is listed on the bottom of the outline.  For this example, the safety goal is clearly impacted by the injuries, but there are several other impacts that need to be considered as well such as the damage to the classroom, evacuation of the school and required emergency response.  Fairfax County has also banned all open flame experiments pending a thorough investigation of this issue which can be considered an impact to the regulatory goal.

Once the Outline is complete, the Cause Map itself is built by asking “why” questions beginning with one of the impacted goals. Starting at the safety goal in this example, the first step would be to ask “why” were 6 people injured?  These injuries occurred because people were burned because there was an uncontrolled fire in a classroom, people were near the fire and no protective gear was worn.  (When there is more than one cause that contributes to an effect, the cause boxes are listed vertically and separated by “and” to show that all causes were required.)  No information has been released to the public about why the students were sitting so near the open flame experiment without any type of safety barrier or why protective gear wasn’t worn, but these are both branches of the Cause Map that should be expanded during a complete investigation.  If the same fire had occurred, injuries may have been prevented or at least been less severe if the students were farther away from the flames or if they had protective gear on to protect them from burns.  It’s important to understand why the experiment was performed as it was in order to develop solutions that could prevent injuries in the future.

There has been a little information released about why the fire was uncontrolled during the experiment.  Eyewitnesses have stated that the teacher was adding more fuel to the fire because it was starting to burn out.  As liquid fuel was added, the fire spread unexpectedly and burning fuel splashed out of the experiment location onto students and the teacher performing the experiment.  The specific details of what occurred during this specific fire have not been released and should be looked at during the detailed investigation.  Once more information is known, the Cause Map could be easily expanded to incorporate it.

The Chemical Safety Board (CSB) is not investigating this incident, but has stated that it is gathering information on it.  The recent accident appears to be similar to three accidents involving open flame experiments that injured children during an 8 week period in 2014.  These three accidents all involved experiments using flammable liquid, a flashback to the bulk containers of fuel and fire engulfing members of the audience.  Following the 2014 accidents, the CSB issued a safety bulletin titled “Key Lessons for Preventing Incidents from Flammable Chemicals in Educational Demonstrations”.   Key lessons listed from the CSB safety bulletin that should be considered when planning open flame experiments are as follows:

– Do not use bulk containers of flammable chemicals in educational demonstrations when small quantities are sufficient.

– Implement strict safety controls when demonstrations necessitate handling hazardous chemicals – including written procedures, effective training, and the required use of appropriate personal protective equipment for all participants.

– Conduct a comprehensive hazard review prior to performing any educational demonstration.

– Provide a safety barrier between the demonstration and audience.

Root Cause Analysis - Incident Investigation

Are Your Vehicle’s Tires Safe?

By ThinkReliability Staff

Four vehicle accidents between February and May of 2014 took 12 lives and injured 42 more. While the specifics of the accidents varied, all four were due to tread separations on tires. Later that year the National Transportation Safety Board (NTSB) hosted a Passenger Vehicle Tire Safety Symposium to address areas of concern regarding passenger vehicle safety due to tire issues. A special investigation report, which was adopted October 27, 2015, provides a summary of the issues and industry-wide recommendations to improve passenger vehicle safety.

There are multiple issues causing safety concerns with tires, and multiple recommendations to mitigate these safety risks. When dealing with a complex issue such as this, it can help to visually diagram the cause-and-effect relationships. We can do this in a Cause Map, or visual root cause analysis. This analysis begins with an impact to the organization’s goals. According to the NTSB report, tire-related accidents cause more than 500 deaths and 19,000 injuries every year in the US. Customer service (customers being members of the public who purchase and/or use tires) is impacted due to a lack of understanding of tire safety. The regulatory goal is impacted due to a lack of tire registration, and the production goal is impacted due to a low recall completion rate. Lastly, the property goal is impacted due to tires that are improperly maintained.

Cause-and-effect relationships are developed by beginning with an impacted goal (in this case, the deaths and injuries) and asking “why” questions. In this case, the deaths and injuries are due to tire-related accidents, of which there are about 33,000 every year in the US. Tire-related accidents includes accidents that are due to tire issues (such as tread separation) caused by improper maintenance or an unrepaired manufacturing issue with a tire (specifically those resulting in a tire recall). While the NTSB is recommending the promotion of technology that may reduce the risk of tire-related accidents, they also made recommendations that can reduce the risk of these accidents in the near term.

From 2009-2013, there were 3.2 million tires recalled in 55 safety campaigns. However, 56% of recalled tires remain in use, because of very low recall work completion rates. In a typical tire recall, only about 20% of recalled tires are returned to the manufacturer. (In comparison, about 78% of recalled cars are repaired.)   Many tires aren’t registered, and if they aren’t, it’s difficult to reach owners when there are recalls. Independent dealers and distributors, which sell 92% of tires in the US, aren’t required to register tires. While it is possible for consumers to look up their own tires to determine if they’ve been recalled, it’s difficult. The full tire identification number may not be printed in an accessible location, and the National Highway Traffic Safety Administration (NHTSA) website for tire recalls was found to be confusing.

The NTSB has recommended that tire manufacturers include the full tire identification number on both the inboard and outboard side walls of each tire so it can be more easily found by consumers. The NTSB has also recommended that the NHTSA, with the cooperation of the tire industry and Congress, if necessary, improve its recall site to allow search by identification number or brand and model, and improve registration requirements and the recall process.

Regarding improper maintenance, the report found that 23% of tire-related crashes involved tire aging and that 50% of drivers use the wrong tire inflation pressure, 69% have an underinflated tire, 63% don’t rotate their tires, and 12% have at least one bald tire. The report found that consumers have an Inadequate understanding of tire aging and service life and recommends developing test and best practices related to tire aging, and developing better guidance for consumers related to tire aging, maintenance and service life.

The NTSB has issued its own Safety Alert for Drivers, which includes the following guidance:

– Register new tires with the manufacturer

– Check your tire pressure at least once a month

– Inflate your tires to the pressures indicated in your vehicle owner’s manual (not on the tire sidewall)

– When checking tire pressure, look for signs of damage

– Keep your spare tire properly inflated and check it monthly for problems

– Rotate, balance and align your tires in accordance with your vehicle owner’s manual

– If you hear an unusual sound coming from a tire, slow down and have your tires checked immediately

To view the Cause Map, including impacted goals and recommendations, click on “Download PDF” above. Or, click here to read the NTSB’s executive summary.

 

Root Cause Analysis - Incident Investigation

Interim Recommendations After Fatal Chemical Release

By ThinkReliability Staff

After a fatal chemical release on November 15, 2014 (see our previous blog for an initial analysis), the Chemical Safety Board (CSB) immediately sent an investigative team. The team spent seven months on-site. Prior to the release of the final report, the CSB has approved and released interim recommendations that will be addressed by the site as part of its restart.

Additional detail related to the causes of the incident was also released. As more information is obtained, the root cause analysis can be updated. The Cause Map, or visual root cause analysis, begins with the impacts to the organization’s goals. While multiple goals were impacted, in this update we’ll focus on the safety goal, which was impacted due to four fatalities.

Four workers died due to chemical asphyxiation. This occurred when methyl mercaptan was released and concentrated within a building. Two workers were in the building and were unable to get out. One of these workers made a distress call, to which four other workers responded. Two of the responding workers were also killed. (Details on the attempted rescue process, including personal protective equipment used, have not yet been released.) Although multiple gas detectors alarmed in the days prior to the incident, the building was not evacuated. The investigation found that the alarms were set above permissible exposure limits and did not provide effective warning to workers.

Methyl mercaptan was used at the facility to manufacture pesticide. Prior to the incident, water accessed the piping system. In the cold weather, the water and methyl mercaptan formed a solid, blocking the pipes. Just prior to the release, the blockage had been cleared. However, different workers, who were unaware the blockage had been cleared, opened valves in the system as previously instructed to deal with a pressure problem. Investigators found that the pressure relief system did not vent to a “safe” location but rather into the enclosed building. The CSB has recommended performing a site-wide pressure relief study to ensure compliance with codes and standards.

The building, which contained the methyl mercaptan piping, was enclosed and inadequately ventilated. The building had two ventilation fans, which were not operating.   Even though these fans were designed PSM critical equipment (meaning their failure could result in high consequence event), an urgent work order written the month prior had not been fulfilled. Even with both fans operating, preliminary calculations performed as part of the investigation determined the ventilation would still not have been adequate. The CSB has recommended an evaluation of the building design and ventilation system.

Although the designs for processes involving methyl isocyanate were updated after the Bhopal incident, the processes involving methyl mercaptan were not. The investigation has found that there was a general issue with control of hazards, specifically because non-routine operations were not considered as part of hazard analyses. The CSB has recommended conducting and implementing a “comprehensive, inherently safer design review” as well as developing an expedited schedule for other “robust, more detailed” process hazard analyses (PHAs).

Other recommendations may follow in the CSB’s final report, but these interim recommendations are expected to be implemented prior to the site’s restart, in order to ensure that workers are protected from future similar events.

To view an updated Cause Map of the event, including the CSB’s interim recommendations, click “Download PDF” above. Click here to view information on the CSB’s ongoing investigation.