How should film washing time be measured and how often is it done?

• A. Visually or with a flow meter with water line within +/- 10%, and performed daily.
• B. Measured weekly with a timer external to the processor.
• C. Only by a calibrated flow sensor with no daily requirement.
• D. Not required to be measured.

Answer: (A)

The wash step must be consistent to remove fixer and other residues from the film; if washing is inadequate, residues can cause image issues and chemical damage. To verify wash time, you check the wash water flow or duration. This is best done by either visually confirming the wash stream runs for the expected period or by using a calibrated flow meter that measures the actual flow rate. The flow line should be within about ±10% of the nominal specification to ensure enough contact and turbulence for proper washing. This check is performed daily because changes in water pressure, valve wear, clogging, or pump problems can alter wash time, and daily verification helps catch and correct those issues before they affect image quality. Regular measurement keeps the process reliable and consistent.