The only truly valid image quality indicator is a material or component, equivalent to the part being neutron radiographed, with a known standard discontinuity, inclusion, omission or flaw (reference standard comparison part). The SI is designed to substitute for the reference standard, providing qualitative information on hole and gap sensitivity in a single unit. Fabrication in accordance with this practice is vital for accurate and consistent measurements.

This practice shall be followed for the fabrication of all SIs to be used with Method E 545 to determine image quality in direct thermal neutron radiography.

1.1 This practice covers the fabrication of Sensitivity Indicators (SI), which can be used to determine the relative quality of radiographic images produced by direct, thermal neutron radiographic examination.

1.2 The values stated in inch-pound units are regarded as the standard. The SI equivalents given in parentheses in the text are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.