The potential for sour fluids to cause cracks and blisters in pipelines and pressure vessels had been recognized for many years before standard test procedures were developed. Following a number of pipeline ftilures in the 1970s, Task Group T- lF-20 was formed to standardize a test
method to evaluate the resistance of pipeline steels to a form of Hydrogen-Induced Cracking (HIC) described as Stepwise Cracking. The test method was approved in 1984 and reaffmed in 1987. In response to changes in technology and industry requirements, the standard was revised in 1990 to include pressure vessel steels and thin-wall, small-diameter line pipe, and an alternate, low-pH test solution. Additional changes are being considered by Task Group T-lF-20 to assure that the test method addresses current needs