Your device needs to be calibrated and then checked by a Factory Authorized calibration technician. If you have not been certified by Intoximeters to calibrate your EBT, then you should send the device to the factory for calibration or locate an authorized calibration technician in your area.
DOT says that inspection, maintenance, and calibration of EBTs needs to be done according to specific criteria - which are set forth in the manufacturer’s Quality Assurance Plan (QAP). Each of these functions also needs to be performed by specific entities- namely the manufacturer of the EBT, a representative certified by the manufacturer of the EBT, a state health agency, or another appropriate state agency (e.g. law enforcement). (Note: It would be reasonable to assume that the state agencies would have received their training in this area from the manufacturer of the EBT.)
The DOT has purposely limited inspection, maintenance, and calibration functions in attempt to increase the overall reliability of industry test results.
If your EBT has failed an accuracy check, thus requiring a calibration adjustment, you have several options:
Find a properly certified Cal Tech in your area (contact the Training Department),
Get trained as a Cal Tech and perform the calibration yourself (view available classes),
Send the instrument to Intoximeters Technical Service for calibration, or
Use another properly calibrated EBT.