# 1992 Eindhoven
The test, called PENT, consists in measuring the resistance to slow crack growth of precisely notched specimens under constant load in air. The specimen geometry is designed and conditions are chosen so that failure is by slow crack growth as occurs under service in the field. The test conditions for producing failure in the minimum time are given. The correlation between the PENT lifetime and other test methods is presented. Also, the correlation between the PENT lifetime and the expected lifetime of a piping system in the field is presented. Finally, a minimum requirement based on the PENT test is suggested. A piping system that satisfies this minimum requirement is expected to last at least 100 years before a significant number of field failures occur.