Accidents incident, root causes

Each accident/incident should be methodically analyzed using an accident investigation/root cause analysis approach. Because many root cause analysis methods exist, it will be the investigator s responsibility to select the appropriate analysis approach (e.g., barrier analysis). Use of proper accident/incident investigation methods and tracking will lead to intervention, which will successfully prevent further occurrence of these occupational accidents and incidents. 

Sharing of past major incidents with other oil and gas industries provides useful input data for similar process industries in order to identify the most critical barriers and improve their safety processes. One poignant example highlights this matter. In 1998 there was an accident in the gas compression stage of a Middle East oil and gas plant which caused 7 dead as a result of fuel accumulation and vapor cloud explosion which was very similar to the Texas City Refinery disaster on March 23, 2005 in which a distillation tower was overfilled and an uncontrolled release of hydrocarbons led to a major explosion and fires. Fifteen people were killed and 180 were injured in the worst disaster in the United States in a decade. In both incidents, excess hydrocarbons were diverted into a pressure relief system that included a blowdown stack. In the Iranian case, it was equipped with a flare, but one which the operator didn t ignite in Texas City the blowdown stack was not equipped with a flare to burn off hydrocarbons as they were released. As a result, the flammable overflow from the tower entered the atmosphere. Ignition of the escaped hydrocarbons was enabled by startup of a nearby vehicle resulted in the explosion and subsequent fires (Hopkins, 2008). This example shows the repetitive patterns of accidents, and root causes of events all over the world in this sector. The lesson of this paper is that accidents in one country, where the scenarios are very similar, can and should serve as lessons to prevent the same scenario being actualized in other countries. 

Nuclear power has achieved an excellent safety record. Exceptions are the accidents at Three Mile Island in 1979 and at Chernobyl in 1986. In the United States, safety can be attributed in part to the strict regulation provided by the Nuclear Regulatory Commission, which reviews proposed reactor designs, processes appHcations forUcenses to constmct and operate plants, and provides surveillance of all safety-related activities of a utiUty. The utiUties seek continued improvement in capabiUty, use procedures extensively, and analy2e any plant incidents for their root causes. Similar programs intended to ensure reactor safety are in place in other countries. 

In the shorter case studies, only the immediate causes of the errors are described. However, the more extended examples in the latter part of the appendix illustrate two important points about accident causation. First, the precondihons for errors are often created by incorrect policies in areas such as training, procedures, systems of work, communications, or design. These "root causes" underlie many of the direct causes of errors which are described in this section. Second, the more comprehensive examples illustrate the fact that incidents almost always involve more than one cause. These issues will... 

In the following sections, a number of methodologies for accident analysis will be presented. These focus primarily on the sequence and structure of an accident and the external causal factors involved. These methods provide valuable information for the interpretation process and the development of remedial measures. Because most of these techniques include a procedure for delineating the structure of an incident, and are therefore likely to be time consuming, they will usually be applied in the root cause analysis of incidents with severe consequences. 

The first case study describes the application of the sequentially timed event plotting (STEP) technique to the incident investigation of a hydrocarbon leak accident. Following the analysis of the event sequence using STEP, the critical event causes are then analyzed using the root cause tree. 

Root Causes The combinations of conditions or factors that imderlie accidents or incidents. 

Scenario A description of the events that result in an accident or incident. The description should contain information relevant to defining the root causes. 

Thorough and effective analyses of workplace incidents are critical components of a comprehensive safety management system. Yet, many incident analysis processes (i.e., accident investigations) fall short. They frequently fail to identify and resolve the real root causes of injuries, process incidents and near misses. Because the true root causes of incidents are within the system, the system must change to prevent the incident from happening again. 

I often inform the person about the technique before I press them a bit to get to the root cause. Five is not a magic number the number of times you ask the question is situational. It is very effective at framing the conversation and engaging all involved In root cause analysis. Therefore, it is a very useful technique when conducting incident or accident investigations. Chapter 7 will be devoted to that important aspect of world-class safety. 

A future chapter will be devoted to effective incident/accident investigations. Every incident (near miss) or accident provides a continuous improvement opportunity that should result in root cause analysis and corrective actions. Here is a chance to utilize someone with a passion for lean, and his/her problem-solving skill sets, to fill this safety team position. Eilling this role provides another opportunity to develop a future business leader. 

Accident/incident investigation subteam This team is accountable for the continuous improvement of safety by using every incident and accident as a vehicle to get to root causes and corrective actions. The... 

Root cause The one cause that leads all of the others when conducting an investigation of an outcome. In accident or safety incident investigations, the pursuit of effective corrective actions is dependent on defining the root cause of the accident or incident. 

Warnings went unheeded - Findings indicated that most incidents were often preceded by a series of smaller accidents, near misses, or accident precursors. Operations and maintenance procedures must include analysis, root cause investigation, and corrective action. 

Traditionally the only reasons for accident investigations were to appropriate blame and find a guilty party. This will never solve the problem or determine the root causes of downgrading events, and will not fix the real cause of the problem. This is termed prescription without diagnosis. Finding one cause of an accident is totally insufficient, as there are always a number of reasons for an action or incident. 

Participating on workplace teams charged with identifying root causes of accidents, incidents, or breakdowns. 

Figure 10.1 highlights the luck factor that determines the outcome of an undesired event, the important role that near-miss incidents play in loss prevention, and the importance of the accident root causes and their antecedents. This model will help managers look at the bigger picture of accidental loss—the causes, effects, and luck factors—and explains the importance of risk identification and mitigation in the safety process. Similar models on loss causation can be referred to as long as they focus on the bigger picture and do not indicate unsafe employee actions as the main accident causes. 

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