In August 2021, Analysis and Measurement Services Corporation (AMS) reached a key milestone when the Nuclear Regulatory Commission (NRC) approved the Topical Report (TR) on Online Monitoring (OLM) technology (insert TR# here) to extend calibration intervals for pressure, level, and flow transmitters. Since then, several plants have successfully integrated OLM, realizing measurable improvements in efficiency and maintenance planning.

Securing Approvals and Broadening Use

AMS has received License Amendment Request (LAR) approvals for six nuclear reactor units to move forward with OLM implementation. These approvals have allowed for a shift toward condition-based monitoring, resulting in notable reductions in Operations and Maintenance (O&M) costs. LARs have also been submitted for 11 additional nuclear reactor units, signaling continued interest and adoption across the industry.

How OLM Works

OLM technology analyzes historical transmitter data stored in the plant’s computer systems to determine which instruments need calibration. This approach avoids unnecessary calibration work, removing the need for transmitter drift studies or Probabilistic Risk Assessments (PRA), and uses existing infrastructure that does not require physical changes or new hardware installations.