If spilled chemicals evaporate, they may settle on films and cause spotting. Benches
and any accessories must also be washed. It is advisable to sterilize developing
tanks periodically with a 5 percent solution of sodium hypochlorite (bleach). Allow
the sterilizing solution to remain in the tank overnight and then drain and rinse
Due to the sensitivity of X-ray film, cleanliness is very important. Film hangers, funnels, stirring rods, thermometer
and all mixing containers must be washed thoroughly after use. Processing tanks must be scrubbed clean before filling
with fresh solutions. If any solution is spilled, wipe it up immediately.
Keep exposed film away from the direct light of the safelight; exposed films are
more sensitive to illumination from safelights than are unexposed films. Screen-
type films are more sensitive to fogging than non-screen films. In addition,
emulsions are less sensitive when wet so they can be exposed to safelights for longer
periods after immersion in the developing solution.
All mixing vessels SHALL be enamelware, stainless steel, glass, hard rubber or glazed earthenware. Metal containers
such as aluminum, iron and zinc will contaminate the solutions and result in fog on the developed radiograph and
therefore, SHALL not be used. In accordance with the manufacturer's instructions, all chemicals must be mixed
Always handle the film at the extreme edges to avoid fingerprints.
The punched number must beat the bottom of the hanger to prevent streaking due to
developer flow through the holes when processing.
This procedure must be performed in the dark room.
a. To remove the film from the cassette or film holder, open up the cassette or film holder completely.
Turn the film over at the edge with the reverse or bottom side up. Do not slide the film out.
b. If the film must be punched for identification, punch the number in the upper right-hand corner.
c. To place the film on the film hanger, grasp one upper corner between the thumb and index finger and
fasten it to the hanger with one of the bottom hanger clips.
d. Fasten the other bottom clip and finally the two top clips.