Fires root causes

When organizations focus on the root causes of worker injuries, it is helpful to analyze the manner in which workplace fatalities occur (see Figure 1-4). Although the emphasis of this book is the prevention of chemical-related accidents, the data in Figure 1-4 show that safety programs need to include training to prevent injuries resulting from transportation, assaults, mechanical and chemical exposures, and fires and explosions. 

On October 30, 1998, a flammable gas release led to gas migration to a non-electrically classified Electrical and Instrumentation (E l) Room. The flammable gas was ingested into the exterior heating and ventilation inlet duct. When the 480 volt primary power switch, within the E l room was remotely shut off, an explosion resulted. The E l module explosion led to a subsequent fire in adjacent production buildings. There were no injuries to personnel. The root cause of the incident was determined to be the failure of management systems... 

Since these have a common cause, they should be considered as simultaneous events for that cause. If two events do not share a common cause, then the probability that they will occur simultaneously is remote and is not usually considered (API RP 521,3.2). Root cause events such as power loss, utility loss, and external fire will often cause multiple other events and hence large relief loads. 

AR175 Root cause analysis for fire events at nuclear power plants. No. 1112, 22 September 1999. 

Piper Alpha, North Sea 1988 167 deaths Fire/explosion of natural gas Multiple and root cause was management related. 

A program whose objective is to minimize incident-based losses. Total loss control is based on studies of near misses or non-injury or damage incidents, and on analysis of both direct and indirect incident causes (root causes). Both injuries and property damages are included in the analysis. Loss control activities include fire prevention, education, inspection, overhaul, and salvage. 

In her view there is a Root Cause Seduction search, which leads to an organization that fixes the symptoms but not the process that lead to those symptoms. The organization is in continual fire-fighting mode and the organization is having the same incident repeated over and over [13]. 

If you ask the National Aeronautics and Space Administration (NASA), such conversions are very important. In 1999 NASA lost the 125 million Mars Climate Orbiter just as it was approaching the red planet. The problem. Unit conversion. NASA s scientists and engineers in Pasadena worked in metric units, and assumed that the thrust data for the rockets on the orbiter they received from Lockhead Martin Aeronautics in Denver, which built the spacecraft, were in metric units. In reality, the units were imperial (pounds, miles, etc.), and the lack of conversion meant that the orbiter approached Mars from an altitude of 60 kilometers instead of 150 kilometers. As the result the friction from the atmosphere caused the craft to bum up. The root cause of the failure was that the flight system vwitten to take thrust instmctions used the metric unit newton (N), while the software on the ground, which generated those instmctions used the imperial measure pound-force (Ibf). As a result, the thmster firings were underestimated by a factor of 4.45 (1 Ibf = 4.45 N). 

It is important to reduce the chances of a recurrence to identify the immediate, underlying and root causes of a fire. The immediate causes of the fire will often involve the initiators of fire. Whereas the underlying causes will be factors that lead to the initiators starting a fire. The root causes, as with all adverse events, will be failures in management systems. Unless the root causes are identified , adequate measures to reduce the risk cannot be taken. 

It can be seen that for each example in Table 12.9 one of the root causes of all fires is likely to be an inadequate fire risk assessment (FRA). It may be that the FRA failed to identify a particular fire risk or that the fire risk control measures that the FRA identified were not fully effective or in place. It may also be that the FRA had identified... 

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. 

Trailers docked while mnning with their lights left energized are the root cause of most dock fires because they can cause ordinary seals to burn. Heat-dissipating seals can put an end to such a fire before it has a chance to start. 

The maimer in which the list of critical behaviors is developed ensures a degree of content-based validity. These are behaviors that are related to incidents or that safety professionals believe to involve risk. Krause argues that behavior is the final common path for accidents. Although this is easy to demonstrate when people faU, catch their hand in a machine, or are struck by a falling object, the connection is often much more complicated when a plane crashes or a refinery catches fire. There are undoubtedly acts and failures to act involved in each of these, but an analysis of individual behavior is a rather inefficient way to understand the root causes of these events. 

Colonel Scott A. Snook, Ph.D., in Friendly Fire introduced the term practical drift. The theory of practical drift emerged from Snook s root cause analysis of a 1994 friendly fire accident in which two U.S. Air Force F-15C Eagle fighter jets patrolling the No-Hy-Zone over northern Iraq shot down two U.S. Army Black Hawk UH-60 helicopters. Twenty-six peacekeepers lost their lives. 

Stretching of the muscle is sensed in the muscle spindle and leads to firing in muscle spindle afferent. These nerves travel via the dorsal root and synapse in the anterior horn of the spinal cord directly with the motor neurone to that muscle. They stimulate firing of the motor neurones, which causes contraction of the muscle that has just been stretched. The muscle spindle afferent also synapses with inhibitory interneurons, which inhibit the antagonistic muscles. This is called reciprocal innervation. 

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