Hastings, Carlton H.
Physicist, Watertown Arsenal, Watertown, Mass.
Pages: 10 Published: Jan 1950
At the risk of being caught in the crossfire of controversy that has accompanied the subject of radiographic sensitivity since the days of the first radiographic procedure specification, the author will attempt to express his thoughts on this subject in an effort to present a more complete and modern picture of the problem than has been done in the past. Much of the discussion to be presented will not be new but will be presented in the light of recent experiences in the preparation of a general radiographic procedure specification. “The term radiographic sensitivity refers to a combination of contrast and definition which determines the clarity with which variations in dimensions and radiographic opacity of the object being examined are depicted on the exposed film. This quality is, of course, directly related to the ability of the radiograph to reveal defects or other sought for conditions in the object but the latter ability is very difficult to express quantitatively.” It is interesting to note that of several textbooks and manuals on radiography examined, not one presented a word definition and only one of them made specific mention of this term. The one book noted which did present a picture of the significance of the term did so by means of a chart showing the breakdown of factors influencing radiographic sensitivity, a very clear means of explanation. The above definition does not state the meaning of the term nearly as well as it states the factors upon which it depends. This fact is somewhat unfortunate but nonetheless significant. The fact that it is difficult to define directly and the fact that it is incapable of quantitative evaluation leads one to question the advisability of using the term as the keynote to good industrial radiography at the present time. In an attempt to discover the reason for our failure to be able to evaluate radiographic sensitivity quantitatively one must investigate the individual factors involved.
Paper ID: STP47341S