Screen Contact Test Without good contact between the film and
screens of the cassette, detail will be lost on the radiograph.
Therefore, it is necessary to routinely perform a screen contact
test on all of your cassettes. Screen contact tests are required
at least annually by Minnesota Rules, part 4732.1100. Equipment
needed for general radiography: - No significant areas of poor
contact as measured by no less than: (1) 8 wires/inch mesh; or
(2) 7 holes/inch for regular film; (3) 40 wires/inch mesh or
greater for mammography film. - These test tools are generally
encased in acrylic for ease of handling - Densitometer (if
available) Frequency of test: At intervals not to exceed 24
months - Ensure that cassettes to be tested have been allowed to
sit for at least 15 minutes after loading. This will allow for
any trapped air to dissipate. - Place a loaded cassette on top
of the x-ray table and place the wire mesh on top of the
cassette. - Select a standard focal film distance (usually 40")
and center the x-ray be