Bruceton staircase method

Impact tests were performed according to ASTM D5420 using the Gardner impact tester. This method is used to determine the energy to fracture rigid polymers. In our ease, the Bruceton staircase method (up and down) was performed. A minimum of 20 samples were tested for each condition. 

T.W. Anderson et al, NAVORD Rept 65-46 (1946) described seven varieties of staircase method including the Bruceton test. Natrella (Ref 42a) also gives several References to other discussions of the up-and-down or staircase method of testing... 

Run-Down Method. A statistical testing procedure developed at Frankford Arsenal, Philadelphia (Ref 1) which produces a more complete frequency and probability of reaction curve than the Bruceton, up-and-down, or staircase methods (see under Impact, Initiation of Explosion by in Vol 7, 136-R to I37-L). Although a larger number of tests is used than in the latter procedures, the method makes possible a better evaluation of the distribution of the population. Starting at a level expected to be between 0%... 

The up-and-down method, also called the Bruceton or staircase method, is a widely used statistical procedure for the determination of the height at which 50% of the samples detonate or react and its standard deviation [17,18]. The advantages and disadvantages of the method are described elsewhere [18-20] basically the test gives a reliable 50% value but not a reliable standard deviation. The number of tests required at each height also has been investigated [21]. 

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