Scope:

ASTM E1815-18 test method gives a relative means of classifying industrial radiography film systems. The film system consists of the film and the processing system that goes with it. The only direct exposure-type film exposed with lead enhancing screens should be tested using this procedure. This test method cannot accurately measure the performance of films exposed to fluorescent (light-emitting) intensifying screens.

Procedure:

In ASTM E1815-18, measurement equipment is for classification, and the test procedure produces the same results with an uncertainty of less than 5% and a confidence level of 95% for gradient G2, less than 7%, and a confidence level of 95% for gradient G4, and less than 10% and a confidence level of 95% for granularity. Compared to the test method of 7.1 to 7.4 for the film systems to be categorized, this shall conform with ISO/IEC 17025.

Specimen size

The microdensitometer’s inflow aperture must be roughly circular, with a diameter of not less than 1.2 or more than 2x the diameter of the efflux aperture.

Result

In ASTM E803-20, the specific image capture technique employed shall be reported, including the digitization process if film images are digitized, the calculation method(s), and the L/D ratio(s).

Data
G = dD /d log10 K
where:
K is the dose required for density D − Do, and Do is fog and base density.