Radiation Monitoring

CMS Process SIL Monitor

The CMS Interlock SIL is a gamma monitor designed specifically for interlock applications.


The instrument incorporates a high integrity Lab-Impex Systems SIL Safeguard Monitor (SSM) sub-system. The SSM is a safety related product which provides a risk reduction level, suitable for use in SIL 2 applications. This is a uniquely patented hardware only solution, which provides a high integrity alarm relay contact output, for interface to a broad range of industrial applications.



  • Designed and manufactured to meet requirements of the IEC61508 - a safety standard providing a methodical and systematic approach to an instrument lifecycle
  • Instrument safety function is performed by the SIL Safeguard Monitor (SSM) encompassing the high activity alarm as a relay output
  • CMS seamlessly combines both smart diagnostics and high integrity real time SIL diagnostics by means of both visual indication and LCD read-outs
  • Dose rates displayed with easy to read graphical display
  • System Probability of Failure on Demand (PFD) of 4.48x10-3 (meeting the demands of SIL 2), with a Dangerous Undetected Failure Rate (λDU) of 1.69x10-6 failures per million hours. These calculations follow requirements in Part 6 and Part 7 of the IEC61508 standard
  • Support documentation and tools provided to simply application substantiation processesRelay contacts are separate from the main enclosure which prevents tampering the monitor configuration
  • Europe's first product to be independently certified by both SIRA and CASS