Specifications

All IDNIYRA Specifications are published in the IDNIYRA Yearbook (available from the class Treasurer):

The current Specifications are also available here:
IDNIYRA Specifications

In addition to the current printed Specifications, the IDNIYRA Technical Committee occasionally makes Official Interpretations to the Specifications. There interpretations are printed along with the Specifications in the yearbook. Check here for recent additions to the Official Interpretations:
Technical Committee Interpretation

The Technical Committee has also issued some "recommended practices" for measuring DN's against the Official Specifications. Check these recommendations here:
Specification Measurements