Refer to the following specifications : ASTM E144-94, British Standards BS 4791-1985

The CAL2K vessels have a built in firing counter which monitors how many determinations a vessel has done. The vessel must be inspected after 5000 firings.

At 4000 firings an alarm is activated to indicate that the vessel will need inspection soon. The vessel can still be used in this mode.

At 5000 firings the vessel is deactivated and no longer used. The vessel must be sent to DDS for inspection. If the vessel is found not to require reconditioning then the counter is reset for another 1000 firings. If the threads are badly worn then the vessel must be reconditioned. After the reconditioning a vessel can be used for another 5000 firings.

The last 2 reconditioning dates are stored in the vessel. The reconditioning dates and firing counter can be read from the CAL2K Calorimeter menu or from the PC software.

BS 4791 states that the maximum time between inspections is 4 years, so if a vessel has not been reconditioned in the past 4 years it should be returned to DDS for inspection.