Beckman Coulter has confirmed a premature decrease in calibration ODs for several lots of bicarbonate OSR6X37. It is possible that all bicarbonate lots may also be impacted by this issue, therefore all lots are subject to this field action. The abnormal decrease in calibrator ODs may result in calibration failures and/or OC failures. the risk of generating falsely elevated, clinically impactful patient test results is remote. Recall start date: April 3, 2023