Starting with the 2002 Edition, the long standing practice of issuing addenda was eliminated. Further, the editions were changed from a three year cycle to a two year cycle. This book is based on the 2008 Edition. The primary reason for the change was that the addenda service was incompatible with electronic publishing for ASME.
Significant changes can occur in each Edition. An engineer whose practice includes process piping should keep a current copy of the Code. New Editions may be obtained from ASME.
The elimination of addenda service can add an additional year between the passing of a Code change and its publication. To address this, if a Code change is considered to be sufficiently urgent, it may be issued as a Code Case. Code Cases may be used as soon as they are approved; there is no need to wait for publication. They will be posted on the ASME B31.3 Section Committee website (see Section 1.8). Note that Code Cases are essentially optional rules.
Errata are corrections to typographical errors and the like. Code interpretations and errata are posted on the ASME web site. #Little_PEng