Bird Triangle

An expression for the pressure flow through an isosceles triangle was derived by Bird et al. [25] by following the variational principle due to von Helmholtz. Other expressions have been proposed by Kozicki et al. [26, 27], who used a simple geometric parameter method to predict the pressure drop-flow rate relationship in flow channels of arbitrary cross-section. Following Bird s approach, the output-pressure relationship for an isosceles triangle can be written as ... 

Bird went on further to look at a wide range of accident reports across a large number of companies in America. In 1969 he analysed the information and generated the Bird Accident Ratio Triangle . See Fig. 1.4 and Further Reading at the end of this chapter. 

The basis of the Heimich triangle or the Bird-Heinrich triangle as it is known in modified form (see Chapter 1), is the careful collection of data over a range of indnstries on different types of accidents. The accidents can be classified as ... 

Figure 5.3 F E Bird s well-known accident triangle.

In 1969, F E Bird collected a large quantity of accident data and produced a well-known triangle (Figure 5.3). 

FIGURE 15.7 Bird s accident triangle. (Adapted from Jones, S. et al., Journal of Loss Prevention in the Process Industries, 12, 59-67,1999.)... 

Near misses - research shows that for every major event there are a corresponding number of less serious events. In 1969, Frank Bird carried out a study of accidents and what he termed critical incidents and developed his accident triangle illustration in Figure 12.2. 

Figure 1. Kinetic response of substrate oxidation (triangles) and basal proton leak (circles) to AF. (A) ROS production response of both kinetics to AW. (B) In skeletal muscle mitochondria from control (open symbols) and heat-stressed(closed symbols) birds.

Various studies have identified that a tiered relationship exists between the severity of an incident and its frequency of occurrence (Heinrich 1931, Bird 1966, British Safety Council 1975, UK HSE 1993, lET 2009). These studies have concluded that for major injuries (i.e., fatal or serious), a large number of minor injuries and numerous non-injury events typically occur. A definitive numerical relationship has not be established (e.g., 1 to 30 to 300 or 1 to 10 to 600), but the principle and general magnitudes have been accepted by the industry and safety professionals (See Figure 2.6). One of the more important points this drives home is that there are more oppor-tnnities to identify incident canses by increasing the focus on incidents at the lower end of the triangle where there are statistically more opportunities to learn and apply corrective actions. 

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