Monthly Archives: October 2015

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.

Uncategorized

Not all McDonald’s franchise owners “lovin” the new menu

By Kim Smiley

Are you “lovin’ it” now that McDonald’s offers breakfast all day? If so, you are not alone because McDonald’s has stated that extended breakfast hours had been the number one request by customers. After recent declines in sales, McDonald’s is hoping that all-day breakfast will boost profits, but some franchise owners are concerned that extending breakfast hours will actually end up hurting their businesses.

Offering breakfast during the day is not as simple as it may sound because McDonald’s are now required to offer breakfast in addition to their regular fare.   Cooking only hash browns in the fryers is inherently simpler than figuring out how to cook both hash browns and fries at the same time. Basically, attempting to prepare breakfast simultaneously with traditional lunch and dinner items creates a more complicated workflow in the kitchen. Complication generally slows things down, which can be a major problem for a fast food restaurant.

If customers get annoyed at increased wait times, they may choose to visit one of the many other fast food restaurants, rather than McDonald’s, for their next meal out. Many franchisees are investing in more kitchen equipment and increasing staffing to support extended breakfast hours, both of which can quickly eat into the button line.  Increased profits from offering all-day breakfast will need to balance out the cost required to support it or franchise owners will lose money.

Franchise owners have also expressed concern that customers may spend less money now that breakfast is an option after 11 am.  Breakfast items in general are less expensive than other fare and if customers choose to order an egg-based sandwich for lunch rather than a more expensive hamburger it could potentially cut into profits.  It all depends on the profit margin on each individual menu item, but restaurants need to make sure they aren’t offering items that will compete with their more profitable offerings.

The changing menu also has the potential to frustrate customers (and frustrated customers will generally find somewhere else to buy their next lunch).  The addition of all-day breakfast has resulted in menu changes at many McDonald’s and more menu variability between franchises.  The larger the menu offered the more difficult it is to create cheap food quickly so some less popular items like wraps have been cut at many McDonald’s locations to make room for breakfast.  If you are a person who loves wraps and doesn’t really want an egg muffin, this move is pretty annoying.  The other potential problem is that most McDonald’s are only offering either the English muffin-based sandwiches or the biscuit-based sandwiches (but not both) after the traditional breakfast window.  So depending on the McDonald’s, you may be all fired up for an all-day breakfast Egg McMuffin to be told that you still need to get there before 10:30 am to order one since about 20 percent of McDonald’s have chosen to go with biscuit-based breakfast sandwiches instead.

 

There are multiple issues that need to be considered to really understand the impacts of switching to all-day breakfast.  Even seemingly simple “problems” like this can quickly get complicated when you start digging into the details.  A Cause Map, a visual root cause analysis, can be used to intuitively lay out the potential issues from adding all-day breakfast to menus at McDonald’s.  A Cause Map develops cause-and-effect relationships so that the problem can be better understood.  To view a Cause Map for this example, click on “Download PDF” above.

Studies have found that at least one quarter of American adults eat fast food everyday (which could be its own Cause Map…) so there are a lot of dollars being spent at McDonald’s and its competitors. Only time will tell if all-day breakfast will help McDonald’s gobble up a bigger market share of the fast food pie, but fast food restaurants will certainly continue trying to outdo each other as long as demand remains high.

Uncategorized

Invasive Pythons Decimating Native Species in the Everglades

By Kim Smiley

Have you ever dreamed of hunting pythons?  If so, Florida is hosting the month-long 2016 Python Challenge and all you need to do to join in is to pay a $25 application fee and pass an online test to prove that you can distinguish between invasive pythons and native snake species.

The idea behind the python hunt is to reduce the population of Burmese pythons in the Florida Everglades.  As the number of pythons has increased, there has been a pronounced decline in native species’ populations, including several endangered species.  Researchers have found that 99% of raccoons and opossums have vanished along with 88% of bobcats, along with declines in nearly every other species.  Pythons are indiscriminate eaters and consume everything from small birds to full-grown deer.  The sheer number of these invasive snakes in the Florida Everglades is having a huge environmental impact.

The exact details of how pythons were released into the Everglades aren’t known, but genetic testing has confirmed that the population originated from pet snakes that were either released or escaped into the wild. Once the pythons were introduced into the Everglades, their number quickly grew as the python population thrived.  The first Burmese python was found in the Florida Everglades in 1979 and now there are estimated to be as many as 100,000 of the snakes in the area.

There are many factors that have led to the rapid growth in the python population.  They are able to live in the temperate Florida climate, have plentiful food available, and are successfully reproducing.  Pythons produce a relatively large number of eggs (an average of 40 eggs about every 2 years) and the large female python protects them.  Hatchling pythons are also larger than most hatchling snakes, which increases their chance of surviving into adulthood.  There are very few animals that prey on adult pythons.  Researchers have found that alligators occasionally eat pythons, but that the relationship between these two top predators can go both ways and pythons have occasionally eaten alligators up to 6 feet in length.  The only other real predators capable of taking down a python are humans and even that is a challenge.

Before a python can be hunted, it has to be found and that is often much easier said than done. Pythons have excellent camouflage and are ambush predators that naturally spend a large percentage of the day hiding.  They also are semi-aquatic and excellent climbers so they can be found in both the water and in trees.  Despite their massive size (they can grow as long as 20 feet and weigh up to 200 pounds), they blend in so well with the environment that researchers even have difficulty finding snakes with radio transmitters showing their locations.

The last python challenge was held about 3 years ago and 68 snakes were caught.  While that number may not sound large, it is more snakes than have been caught in any other month.  The contest also helped increase public awareness of the issue and hopefully discouraged any additional release of pets of any variety into the wild.  For the 2016 contest, officials are hoping to improve the outcome by offering prospective hunters on-site training with a guide who will educate them on swamps and show them areas where snakes are most likely to be found.

To view a Cause Map, a visual root cause analysis format, of this issue click on “Download PDF” above.  A Cause Map intuitively lays out the cause-and-effect relationships that contributed to the problem.

You can check out some of our previous blogs to view more Cause Maps for invasive species if you want to learn more:

Small goldfish can grow into a large problem in the wild

Plan to Control Invasive Snakes with Drop of Dead Mice

Root Cause Analysis - Incident Investigation

NTSB recommends increased oversight of DC Metro

By Kim Smiley

On September 30, 2015, the National Transportation Safety Board (NTSB) issued urgent safety recommendations calling for the Federal Railroad Administration to take over the task of overseeing the Washington, DC Metro system. The NTSB has determined that the body presently charged with overseeing it (the Tri-State Oversight Committee) doesn’t provide adequate independent safety oversight.  Specifically, the Tri-State Oversight Committee doesn’t have the regulatory power to issue orders or levy fines and lacks enforcement authority.

The recommendations resulted from findings from the ongoing investigation into a smoke and electrical arcing accident in a Metro tunnel that killed one passenger and sent 86 others to the hospital.  (To learn more, read our previous blog “Passengers trapped in smoke-filled metro train”.) The severity of damage done to the components involved in the arcing incident have made it difficult to identify exactly what caused the arcing to occur, but the investigation uncovered problems with other electrical connections in the system that could potentially lead to similar issues if not fixed.

Investigators found that some electrical connections are at risk of short circuiting because moisture and contaminants may get into them because they were improperly constructed and/or installed.  The issues with the electrical components were not identified prior to this investigation which raises more questions about the Metro’s inspection and maintenance programs.  Although the final report on the incident has not been completed, the NTSB issued recommendations in June to address these electrical short circuit hazards because they required “immediate action” to ensure safety.

Investigators have found other issues with the aging DC Metro system such as leaks allowing significant water into the tunnels, issues with inadequate ventilation and questions about the adequacy of staff training.   The final report into the deadly arcing incident will include recommendations that go far beyond fixing one electrical issue on one run of track.

This example is a great illustration of how digging into the details of one specific problem will often reveal information about how to improve reliability across an organization. It may seem overwhelming to tackle organization-wide improvements, but often the best way to start is with an investigation into one issue and digging down into the details.

Root Cause Analysis - Incident Investigation

5 killed and dozens injured when duck tour boat collides with bus

By Kim Smiley

Five people were killed and dozens more injured when an amphibious Ride the Ducks tour boat collided with a charter bus in Seattle on September 24, 2015.  The circumstances of the accident were particularly unfortunate because two large vehicles carrying tour groups across a busy bridge were involved.  Traffic was mangled for hours as emergency responders worked to treat the high number of victims, investigate the accident and clear the roadway.

The National Transportation Safety Board (NTSB) is investigating the accident to determine exactly what led to the collision and if there are lessons learned that could help reduce the risk of a similar crash in the future.  Potential issues with the duck boat are some of the early focuses of the investigation.  In case you are unfamiliar, duck boats are amphibious landing craft that were used by the U.S. Army during World War II that have been refurbished for use as tour vehicles that can travel on both water and land to give visitors a unique way to experience a city.  Their military designation DUKW was changed to the more user-friendly duck boat moniker that is used by many tour companies throughout the world.

Eyewitnesses of the accident have reported that the duck boat unexpectedly swerved while crossing the bridge, slamming into the driver’s side of the tour bus.  Reports are that the left front wheel of the duck boat locked up and the driver lost control of the vehicle.  NTSB investigators have stated that the duck boat didn’t have a recommended axle repair done that was recommended in 2013 and that they are working to determine whether or not this played a role in the accident.

Investigators are also looking into whether or not Seattle Ride the Ducks was notified of the repair.  Photos of the wrecked duck boat show that the front axle sheared and the left wheel popped off the vehicle, but it hasn’t been conclusively determined whether the damage was the cause of the accident or occurred during the accident.  The issues with the axle certainly seem like a smoking gun, but a thorough investigation still needs to be performed and the process will take up to a year.  If there was a mechanical failure on the duck boat unrelated to the already identified axle issue, that will need to be identified and reviewed to see if it applies to other duck tour vehicles.

This severity of this accident is raising concerns about the overall safety of duck tours.  The duck boat involved in this accident underwent regular annual inspections and was found to meet federal standards.  If a mechanical failure was in fact involved, hard questions about the adequacy of standards and inspections will need to be asked.  The issue of the recommended repair that was not done also raises questions about how the recommendations are passed along to companies running duck boat tours as well as incorporated into inspection standards.

Click on “Download PDF” above to see an outline and Cause Map of this issue.