Development of a leak-before-break procedure for pressurized components

For pressurized components there is an increasing interest in the use of leak-before-break arguments to show that defects will behave in a failsafe manner by growing in such a way as to cause a detectable leak before a disruptive failure of the pressure boundary can occur. The authors' company operates a wide variety of plant and has recognized the need for a flexible leak-before-break procedure which can be applied in a variety of different situations rather than the more rigid code approach adopted for LWR piping for example in NUREG-1061. This paper describes the development of such a procedure and discusses some of the key aspects of the leak-before-break procedure