English to Italian Medical Medical: Instruments Monitor parametri vitali

"Grade" è la parola incriminata che, in questo caso, non riesco a collocare all'interno della seguente frase:

clinical laboratory grade multi wavelength optical oximeter

Ecco l'intero passsaggio:

These oximeters have SpO2 calibration tables which were originally generated by monitoring desaturated human patients or volunteers and matching their displayed SpO2 value to the value determined by sampling arterial blood and measuring functional SaO2 with a ****clinical laboratory grade multi wavelength optical oximeter**** (i.e., co-oximeter).
The final SpO2 calibration curve was then generated based upon numerous patients’ data over the range of 40 to 99% SaO2.

Thanks!