By ThinkReliability Staff
On August 14, 2003, over 50 million people in the U.S. and Canada were without power, some for several days. Damages from the loss of power – including damaged refrigerated items and looting – totalled approximately $6 billion (U.S.). 508 generating units shut down, resulting in the loss of border and port control systems. After the blackout, a U.S.-Canada Power System Outage Task Force was appointed to investigate the cause. We will use the data they obtained to perform a root cause analysis of the event. A thorough root cause analysis built as a Cause Map can capture all of the causes in a simple, intuitive format that fits on one page.
The blackout was triggered by a shut-down cascade, unsustainable power surges in numerous transmission lines. This occurred due to a supply/demand mismatch – a large decrease in available power without load shedding (where operators drop some consumers off the grid to prevent outages). Operators did not shed loads because they weren’t warned of impending outages, due to a lack of communication from FirstEnergy, the company whose lines began shutting down first, and a lack of warning by the regional coordinator.
The decrease in available power was due to a key transmission line being shut down. This happened because the line contacted overgrown trees when it sagged due to a power surge because other, smaller lines shut down when they sagged and touched overgrown trees. The lines originally sagged due to power surges caused by an automatic shutdown of a power generating unit. The power surge could have been stopped by operators shedding loads, but they did not because they were not immediately aware of problems, thanks to a failure in their grid monitoring equipment, and due to a lack of training.
Due to the complexity of the event, it is possible to make a much more detailed Cause Map. As with any investigation the level of detail in the root cause analysis is based on the impact of the incident on the organization’s overall goals. For example, this map has 21 boxes. The detailed map that includes the findings of the Task Force has more than 70 boxes, and is at a more appropriate detail to find solutions to ensure that this sort of energy reliability problem does not happen again.
By ThinkReliability Staff
Currently, more than 43 million Americans smoke. Why does this happen, and what effect does it have? We will do a very simplistic root cause analysis. A thorough root cause analysis built as a Cause Map can capture all of the causes in a simple, intuitive format that fits on one page.
Smoking leads to an estimated 440,000 premature deaths each year. This includes deaths caused by smoking and by exposure to secondhand smoke. Additionally, 8.6 million people suffer from smoking-related illnesses. And, 900 infant deaths are caused annually from smoking during prengnancy. These are all impacts to the safety goal. The deaths and diseases are caused because smoking raises the risk of cancer, cardiovascular disease, and respiratory disease. The first two are caused by exposure to tobacco smoke (including secondhand smoke) and the third is caused by inhalation of smoke. Either way, the cause is that many people smoke cigarettes.
Why do people smoke? Well, it’s because they start smoking and because it is extremely difficult to quit. There are many reasons why it is difficult to quit. Some of these reasons are: cigarettes are extremely addictive, severe withdrawal symptoms cause relapses, smokers have a lack of assistance in quitting, they are afraid of weight gain, and there is a lack of increase in the cost of cigarettes. This last one sounds odd, but studies have shown that an increase in the cost of cigarettes decreases the number of smokers. However, the cost of cigarettes does not reflect the true cost of cigarettes (based on health costs and productivity losses), and the small increase in taxes (which has not kept up with inflation) is offset by cigarette company promotions.
People start smoking because of the positive imagery of smoking – the heavy advertising and promotion of cigarettes, smoking in popular culture (mainly movies), and the lack of counter-advertising by federal organizations and anti-smoking campaigns. Additionally, most smokers (90%) start as children (before the age of 18) because cigarettes entice children, there is a lack of counseling against their use, teens may suffer from peer pressure encouraging, and teens are more susceptible to addiction than adults.