Monthly Archives: June 2010

Root Cause Analysis - Incident Investigation

Containment Cap Removed from Gulf Oil Leak

By ThinkReliability Staff

Last Wednesday, another set back occurred in the attempt to stem the flow of oil in the Gulf of Mexico from the a well head that was damaged when the Deepwater Horizon Oil Rig exploded on April 20 and sank 36 hours later .

The containment cap used to siphon oil from the damaged well head for the last three weeks had to be temporarily removed for more than 11 hours.  Before being removed, the containment system was sucking up about 29,000 gallons an hour.

So what happened?  Why remove a containment cap that had been working successful?

A root cause analysis of this problem can be built as a Cause Map.  A Cause Map is started by considering the impact to the goals and asking “why” questions to add Causes.  In this example, the first goal we will consider is the Environmental Goal.  Obviously, the environmental goal is impacted because there was additional oil released to the environment because the cap was removed.

Continuing to ask “why” questions we can add additional causes.  The cap was removed because the ship connected to the containment cap system needed to be moved away from the well because there a safety concern because of the potential for an explosion.

There was an explosion concern because there was evidence that flammable gas was flowing up from the well head because liquid was being pushed out of a valve in the containment system.  This gas was getting into the containment cap system because an underwater vent was bumped by one of the remote-controlled submersible robots being used to monitor the damaged well.

More detail could be added to the Cause Map by continuing to ask why questions.  The detailed Cause Map could then be used to develop solutions that could be implemented to help prevent the problem from reoccurring.

Click on the “Download PDF” button above to view an initial Cause Map.

The containment cap was put back into place around 9 pm on June 23.  The efforts to contain and clean up the oil spill will continue for months and possibly years to come, but at least this small issue has been fixed.

Root Cause Analysis - Incident Investigation

Mine Explosion in Colombia

By Kim Smiley

A coal mine explosion in Amaga, Colombia on June 16, 2010 has left at least 18 dead, 1 injured and at least 53 people unaccounted for, and presumed dead.  The deaths and injuries resulted from a fireball caused by an explosion.

Every explosion is caused by four factors: heat, fuel, oxygen and confinement.  In this case, the fuel was methane gas that had built up in the mine.  Methane is naturally produced as a byproduct of coal mining.  The methane was not removed from the mine because the mine lacked a methane ventilation pipe.  Additionally, the workers at the mine did not realize that methane levels were high because there was no gas detection system at the mine.

The number of dead and missing is so high because more people than usual were at the mine – the explosion happened during shift change.  Rescue efforts have been delayed by the high levels of gas in the mine, further increasing the number of deaths.

By clicking “Download PDF” above, you can view the thorough root cause analysis built as a Cause Map in a simple, intuitive format that fits on one page.

Even more detail can be added to this Cause Map as the analysis continues. As with any investigation the level of detail in the analysis is based on the impact of the incident on the organization’s overall goals.

Root Cause Analysis - Incident Investigation

UPDATE: Convictions Result from Bhopal Tragedy

By ThinkReliability Staff

In a previous blog, we outlined the two theories of a 1984 tragedy in Bhopal that resulted in approximately 15,000 deaths. On Monday, June 7, 2010 (nearly 16 years after the incident) 7 former Union Carbide senior employees were convicted of “death by negligence” by an Indian court.  The sentence was two years in jail and a fine of 100,000 rupees (just over $2,000 U.S.).  One former employee who was also charged has since died.  The Union Carbide subsidiary which owned the plant at the time of the leak was also ordered to pay 500,000 rupees as well.

Memorial for those killed and disabled by the toxic gas release.

The charges against the company and the senior officials had been reduced from culpable homicide by India’s supreme court in 1996.  The head of Union Carbide has also been charged but extradition requests remain outstanding.

The recent court case has highlighted not only the problems that led to the chemical leak, but problems that result in massive delays in the Indian court system.  The Law Minister has admitted the delay and said “We need to address that.”

Although the court did not release additional information with their ruling, this appears to support the theory that the an equipment or safety system failure (and not employee sabotage) caused the leak.

Root Cause Analysis - Incident Investigation

Recreational Water Illnesses

By ThinkReliability Staff

Last year we wrote a blog about preventing pool injuries, specifically slipping and drowning. However, there’s a lesser known risk from a pool – getting sick from swimming. This is officially known as “recreational water illness” or RWI, and normally involves diarrhea. RWI is estimated to affect approximately 1,000 people a year (according to WebMD) and can cause death, especially in immune-compromised people.

We can perform a proactive root cause analysis to determine what causes these illnesses. Essentially, a person consumes germs by ingesting pool water that contains germs. Pool water becomes contaminated when germs enter the pool from fecal matter. (Easier said than done. Did you know that the average person is wearing 0.14 grams of fecal matter?) So please, keep fecal matter out of the pool. Take a shower before you get in and make sure your kids are using the bathroom regularly elsewhere. (Not surprisingly, kiddie pools are the ‘germiest’.)

Now, pools are treated to prevent these germs from proliferating. However, some combinations of pool chemicals and germs take much too long to work to be effective. (For example, cryptosporidium takes 7 days to be killed in chlorine.) Some pools aren’t getting enough chemicals due to inadequate maintenance. And, there’s some stuff you can put in the pool – namely urine, sunscreen, and sweat – that interacts with chlorine and reduces the effective volume in the pool. So, even though urine itself doesn’t contain germs, don’t pee in the pool. And again, take a shower.

Our solutions to RWI – take a shower, don’t perform any bodily functions in the pool, and don’t swallow the pool water. However, that works for you and your family, but what about the unwashed masses in the pool? The CDC recommends you buy your own water testing kit and test the pool water before you get in. Make sure there’s a pool treatment plan and that it’s being followed, and that all ‘accidents’ are reported immediately. (Yep, even if they’re your fault.) Then lay back, relax, and enjoy your swim.