Monthly Archives: February 2014

Root Cause Analysis - Incident Investigation

1 Dead and 27 Hospitalized from Carbon Monoxide at Restaurant

By Holly Maher

On Saturday evening, February 22, 2014, 1 person died and 27 others were hospitalized due to carbon monoxide poisoning.  The individuals were exposed to high levels of carbon monoxide that had built up in the basement of a restaurant.  The restaurant was evacuated and subsequently closed until the location could be deemed safe and the water heater, located in the basement, was inspected and cleared for safe operation.

So what caused the fatality and 27 hospitalizations?  We start by asking “why” questions and documenting the answers to visually lay out all the causes that contributed to the incident.  The cause and effect relationships lay out from left to right.

In this example, the 1 fatality and 27 hospitalizations occurred because of an exposure to high levels of carbon monoxide gas, which is poisonous.  The exposure to high levels of carbon monoxide gas was caused not only by the high levels of carbon monoxide gas being present, but also because the restaurant employees and emergency responders were unaware of the high levels of carbon monoxide gas.

Let’s first ask why there were high levels of carbon monoxide present.  This was due to carbon monoxide gas being released into the basement of the restaurant. The carbon monoxide gas was released into the basement because there was carbon monoxide in the water heater flue gas and because the flue gas pipe, intended to direct the flue gas to the outside atmosphere, was damaged.  The carbon monoxide was present in the flue gas because of incomplete combustion in the water heater.  At this point in the investigation, we don’t have any further information.  This can be indicated as a follow-up point on the cause map using a question mark.  We have also identified the reason for the flue gas pipe damage as a question mark, as we do not currently have the exact failure mechanism (physical damage, corrosion, etc.) for the flue gas pipe.  What we can identify as one of the causes of the flue gas pipe failure is an ineffective inspection process.  How do we know the inspection process was ineffective?  Because we didn’t catch the failure before it happened, which is the whole point of requiring periodic inspections.  This water heater had passed its annual inspection in March of 2013 and was due again in March 2014.

If we now ask the question, why were the employees unaware of the high levels of carbon monoxide present, we can identify that not only is carbon monoxide colorless and odorless, but also there was no carbon monoxide detector present in the restaurant.  There was no carbon monoxide detector installed because it is not legally required by state or local codes.  The regulations only require carbon monoxide detectors to be installed in residences or businesses where people sleep, i.e. hotels.

Once all the causes of the fatality and hospitalizations have been identified, possible solutions to prevent the incident from happening again can be brainstormed.  Although we still have open questions in this investigation, we can already see some possible ways to mitigate this risk going forward.  One possible solution would be to legally require carbon monoxide detectors in restaurants.  This would have alerted both employees and responders of the hazard present.  Another possible solution would be to require more frequent inspections of this type of combustion equipment.

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

 

Root Cause Analysis - Incident Investigation

Olympic Track Worker Hit By Bobsled

By Kim Smiley

A worker at the bobsled track for the Sochi Winter Olympics was hit by a bobsled on February 13, 2014.  The worker suffered two broken legs and a possible concussion, but is reported to be stable after undergoing surgery.  There was also minor damage done to the track.  Part of a lighting system suspended from the ceiling was replaced and time was needed to clean small plastic shards off the ice.

Investigation into this accident is still underway, but the information that is available in the media can be used to build an initial Cause Map. One of the advantages of using Excel to build Cause Maps is that they can be easily modified to incorporate additional information once the investigation is complete.

When beginning the Cause Mapping process, the first step is to fill in an Outline with the basic background information for an issue.  How an incident impacted the overall organizational goals is also documented on the bottom half of the Outline.  Once the Outline is completed, the Cause Map is built by asking “why” questions. (Click on “Download PDF” above to view a high level Cause Map and Outline for this accident.)

So why was the worker hit by a bobsled?  This occurred because a forerunner sled was sent down the track while the worker was on the track.  The forerunner sled was on the track because they are used to test the track prior to training runs and competitions, and training was scheduled later that day.  Forerunner sleds ensure that ice conditions are good and that all systems, like the timing system, are functional.  People at the top of the track can’t see the entire track so there wasn’t an easy way for them to identify the position of the worker prior to running the sled.  Initial reports are that the normal announcements were made to the workers prior to running the forerunner sled so it doesn’t appear that the people on the top of the track had any reason to suspect a problem.

The worker was on the track doing work to prepare it for the training runs and competition scheduled that day.  We can safely assume that he was unaware that the forerunner sled was running the track at the same time.  Investigators have determined that the worker was using a loud motorized air blower and believe he was unable to hear both the announcement and the approaching bobsled.  Two other workers were also working on the track, but they were able to scramble out of danger as the bobsled approached.  Until the investigation is complete, it won’t be clear if other factors were involved, but it seems the use of loud equipment played a role in the accident.

The final step in the Cause Mapping process is to find solutions to reduce the risk of a problem reccurring.  It appears that the current method of letting workers know to clear the track isn’t adequate in all situations.  Officials will need to modify the process, especially when loud equipment is in use, to ensure the safety of all workers.  Workers need to be on the track at times in order to do their jobs and there needs to be a way to ensure they have moved to a safe location prior to any sled running the track.

It’s worth noting this is not the first time someone has been hit by a bobsled. In 2005, recent silver medalist skeleton racer Noelle Pikus-Pace was hit by a bobsled.  She shattered a leg and ended up missing the 2006 Turin Olympics as a result.  This accident occurred on a different track, but it highlights the dangers of bobsled tracks and the important of ensuring safety.

Root Cause Analysis - Incident Investigation

Concerns Raised About Safety of Olympic Slopestyle Course

By Kim Smiley 

One of the stories making headlines leading up to the start of the 2014 Winter Olympics was concern about the safety of the slopestyle course.  There were early rumblings about the slopestyle course, especially after a few falls during training runs, but the media interest intensified after well-known snowboarder Shaun White withdrew from the event.   There is also a heighten sensitivity to safety concerns after the death of a luger during the last Winter Olympics , which was the first  death in Olympic training or competition since 1964.

Safety of the athletes involved in the Olympics is obviously paramount, but media coverage of slopestyle course safety concerns is also an issue because it created negative press for both the Olympics and the host country.  A Cause Map can be built to help analyze this issue and illustrate all the factors involved with the controversy surrounding the Olympic slopestyle course. (To see a high level Cause Map of this issue, click on “Download PDF”.)

Several athletes fell during training runs on the slopestyle course, which led to questions about course safety.   There were some injuries on the course, the most notable being Torstein Horgmo of Norway who broke his collarbone during a practice run.  Horgmo was a favorite to medal in the event and was unable to compete after his injury, which has to be heartbreaking.

The course is different from the typical slopestyle course, partly because this is the Olympics and the designer wanted an exciting course.   Athletes are getting more air time from the jumps on the course because they are large step-down jumps where the landing zones are below the ramps.  Designing the first Olympic slopestyle course was a unique challenge and there was no precedent.

The weather has been an added challenge for the course designer.  The jumps were created intentionally oversized with plans to modify them as needed to help accommodate melting concerns in the above freezing weather.  It’s much easier to make a jump smaller, as opposed to larger, so designers would rather err on the size of too big.  Rain and warm weather also played havoc with plans to test the course.  A test event scheduled for last February was canceled because of weather.  Tests were scheduled to allow for more time to groom the course prior to the Olympics, but six days of massive rains pushed course completion past schedule.

It’s also worth noting that there is inherent danger in slopestyle.  Slopestyle is an extreme sport with snowboarders performing high intensity tricks in the air.  Factor in the pressure to bring the goods in an Olympic event and snowboarders are going to be pushing their limits.  The falls don’t all happen on the jumps, despite media focus on the large jumps on this course.  Torstein Horgmo’s Olympic-ending crash occurred on the stair set on top of the course.   While a course can be made too dangerous, there will never be a completely safe slopestyle course because of the nature of the sport.

Snowboarder Shaun White made headlines when he pulled out of slopestyle because of injury concerns, but it’s also important to remember that slopestyle isn’t White’s main event.  Although White failed to reach the podium this Olympics, he was the defending gold medalist on the halfpipe and wasn’t willing to risk his chance to compete in that event.  White suffered minor injuries from a crash on the slopestyle course and he didn’t want to impact his halfpipe chances by getting hurt worse.  Halfpipe came after slopestyle so the consequences of a potential injury were high for White.  I’m willing to bet he would have been much more likely to compete in slopestyle if it occurred after the halfpipe event.

The slopestyle course was modified after training runs, which is typical for an untested slopestyle course.  Forty to fifty centimeters were removed from the top deck of the jumps and snow was added to the knuckles of each landing.  The course crew has been credited for listening to athletes’ concerns and being responsive to issues. Lessons learned from the experience with the first Olympics slopestyle course will hopefully help things go smoother next time.  I hope the focus during the next Olympics is on the amazing athletes and not so much on the course.

Root Cause Analysis - Incident Investigation

Volunteer Killed in Helicopter Fall

By ThinkReliability Staff

On September 12, 2013, the California National Guard invited Shane Krogen, the executive director of the High Sierra Volunteer Trail Crew and the U.S. Forest Service’s Regional Forester’s Volunteer of the Year for 2012, to assist in the reclamation effort of a portion of the Sequoia National Forest where a marijuana crop had been removed three weeks earlier.  Because the terrain in the area was steep, the team was to be lowered from a helicopter into the area.

After Mr. Krogen left the helicopter to be lowered, an equipment failure caused the volunteer to fall 40 feet.  He later died from blunt force trauma injuries. The Air Force’s report on the incident, which was released in January, determined that Mr. Krogen had been improperly harnessed.  The report also found that he should have never been invited on the flight.

To show the combination of factors that resulted in the death of the volunteer, we can capture the information from the Air Force report in a Cause Map, or visual root cause analysis.  First it’s important to determine the impacts to the goals.  In this case, Mr. Krogen’s death is an impact to the safety goal, and of primary consideration.  Additionally, the improper harnessing can be considered an impact to the customer service goal, as Mr. Krogen was dependent on the expertise of National Guard personnel to ensure he was properly outfitted.  Because it was contrary to Air Force regulations, which say civilian volunteers cannot be passengers on counter-drug operations, the fact that Mr. Krogen was allowed on the flight can be considered an impact to the regulatory goal.  Lastly, the time spend performing the investigation impacts the labor goal because of the resources used during the investigation.

Beginning with the impacted goal of primary concern – the safety goal – asking “Why” questions allows for the determination of causes that resulted in the impacted goal (the end effect).   In this case, Mr. Kroger died of blunt force trauma injuries from falling 40 feet.  He fell 40 feet because he was being lowered from a helicopter and his rigging failed.  He was being lowered from a helicopter to aid in reclamation efforts and because the terrain was too steep for the helicopter to land.

The rigging failure resulted from the failure of a D-ring which was used to connect the harness to the hoist.  Specifically, the D-ring was not strong enough to handle the weight of a person being lowered on it.  This is because the hoist was connected to Mr. Krogen’s personal, plastic D-ring instead of a government-issued, load-bearing metal D-ring.  After Mr. Krogen mistakenly connected the wrong D-ring, his rigging was checked by National Guard personnel.  The airman doing the checking didn’t notice the mistake, likely because of the proximity of the two D-rings and the fact that Mr. Krogen was wearing his own tactical vest, loaded with equipment, over the harness to which the metal D-ring was connected.

I think Mark Thompson sums up the incident best in his article for Time:   “The death of Shane Krogen, executive director of the High Sierra Volunteer Trail Crew, last summer in the Sequoia National Forest, just south of Yosemite National Park, was a tragedy. But it was an entirely preventable one.  It stands as a reminder of how dangerous military missions can be, and on the importance of a second set of eyes to make sure that potentially deadly errors, whenever possible, are reviewed and reversed before it is too late.”

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