Understanding NRT- Reading 1- 2 of 2- Radiogaphic Testing A

Film Handling
X-ray film should always be handled carefully to avoid physical strains, such
as pressure, creasing, buckling, friction, etc. Whenever films are loaded in
semiflexible holders and external clamping devices are used, care should be
taken to be sure pressure is uniform. If a film holder bears against a few high
spots, such as on an un-ground weld, the pressure may be great enough to
produce desensitized areas in the radiograph. This precaution is particularly
important when using envelope-packed films.
Marks resulting from contact with fingers that are moist or contaminated with
processing chemicals, as well as crimp marks, are avoided if large films are
always grasped by the edges and allowed to hang free. A supply of clean
towels should be kept close at hand as an incentive to dry the hands often
and well. Use of envelope-packed films avoids many of these problems until
the envelope is opened for processing.
Another important precaution is to avoid drawing film rapidly from cartons,
exposure holders, or cassettes. Such care will help to eliminate circular or
treelike black markings in the radiograph that sometimes result due to static
electric discharges.
Charlie Chong/ Fion Zhang