IHS is your source for the NB 23, the must-have code for any pressure vessel inspector in the industry.
First written in 1946, the code covers the rules and guidelines for in-service inspection, repair, and alteration of pressure- retaining items. The ANSI approved NBIC is required in many US and Canadian jurisdictions. It has a 3 year revision cycle with new information added each year through an addenda service.
2015 Edition now shipping. You save 10% off list price.