“Does your earthquake actuated shutoff system suck?”

OK, that was meant to get your attention. 😉

Our happiest clients tend to express the following: a) no false positives, b) our systems did shutdown automatically in response to a major earthquake, and c) our systems did NOT shutdown in response to smaller earthquakes. These clients have been fortunate to experience the full benefit of their earthquake instrumentation.

Other clients are in areas with the potential for large earthquakes, but otherwise, relatively little seismic activity. They haven’t experienced any small earthquakes and aren’t 100% sure their system will perform when there is a major event. Frankly, most of our clients fall into the latter category. The best measure for such systems is the periodic (annual) ‘as found’ through-channel functional test. During a plant shutdown or other opportunity which will not impact the Owner’s operations, physically shake the seismic sensing element and verify that the Owner’s systems shutdown as designed. To truly be informative regarding the readiness of the shutoff system, the ‘as found’ test must be run BEFORE the re-boot or reset of any monitoring systems, actuated valve assemblies, etc. For safety it may be necessary to manually isolate chemicals, control pressures or other potential energy, etc. before executing the test. The point is, run the test as close as possible to normal operating conditions and verify that monitoring systems, alarms and actuated valve assemblies all perform as designed when real shaking is applied.

The most diligent clients will, after performing the through-channel test, direct that the sensing element be removed and shake tested (X&Y axes, minimum) against a reference sensor in order to verify actuation at the prescribed acceleration setpoint (no excessive drift or failure of any axis.) Acceleration setpoint verification work requires specialized equipment, software and technical skills. Most Owners (including commercial nuclear power plants) contract this out to a representative of the OEM or other qualified testing agency.

Multiple false positives or low expectations that your system will perform properly in response to a major earthquake is an indicator that your system isn’t up to par.

Maybe you just need additional sensors for 2/2 or 2/3 voting to avoid false positives- or more rigorous annual inspection, test and preventative maintenance work to exercise ancillary equipment and prove the earthquake monitoring system is performing as designed.

Feel free to ‘tap into’ our experience…call or drop an email to start a conversation about your application.