1.1 This standard provides a practice whereby industrial radiographic imaging systems or specific factors that affect image quality (that is, hardware, techniques, etc.) may be comparatively assessed using the concept of relative image quality response (RIQR) when exposed to X-radiation sources having photon energies from 4 to 25 MeV. The RIQR method presented within this practice is based upon the use of equivalent penetrameter sensitivity (EPS) described within Practice E1025 and Section 5 of this practice. For special applications, the user may design a non-standard RIQI-absorber configuration; however, the RIQI configuration shall be controlled by a drawing similar to Fig. 1. Use of a non-standard RIQI-absorber configuration shall be described in the user's written technique and approved by the RT Level III.