Approx 65 percent of tonometers have calibration errors. Tonometers should be checked at least once a month. If errors are present they should be sent in to factory-trained personnel to clean and calibrate. Optitech Usa offers this service on all models of Applanation Tonometers.
These are the steps Optitech USA takes to calibrate your tonometer:
The unit is first opened and checked for wear and tear.
When no parts need to be replace the calibration process begins.
Upon completion of the calibration process the unit is cleaned externally.
The unit is next repackaged and returned to you.