The test method suggested in OG54 could help improve the coverage of your proof testing and assist in your performance in future compliance assessment and audits.
www.hse.gov.uk/foi/internalops/og/og-00054-appendix4.pdf
This OG54 document covers:
Sensors
- Redundant channels (e.g. in voting arrangements)
- Use of simulation without testing the sensing element
- Sensor diagnostic features
- Sensor reading correctly - use of cross-comparison
- Sensor reading correctly - use of gauges etc.
- Sensor testing tolerance
- Pressure impulse lines or process connections blocked / leaking partially or completely
- Level sensors with test button
- Level sensors - unable to test due to access hazardous substances
- Temperature sensors - process connection
- Flow sensors reading correctly - unable to test
- Interface devices reading correctly
Logic solvers
- Relay Logic redundancy with components
- Redundant channels
- Diagnostic functions in the logic solver (PES, trip amps etc)
- Control System trips
- Trip amps - changing trip settings to test
- Hardwiring logic functions (e.g. timing relays)
Final elements
- Cessation of flow, heat input etc - testing to instruments only
- Valve operation - position indicators
- Valve operation - latent failure modes
- Valve operation - testing solenoids
- Backup arrangements - e.g. accumulators, trip, batteries, backup power
Whole SIS
- Response times
- Ancillary items - trace heating etc.
- In-built diagnostics
- All failure modes - test by operation
- All failure modes - use of overrides
Bespoke In-House Technician Training
If you have four or more Instrument Technicians who need training, then =Method can arrange a bespoke in-house course for you. This could include time on-site prior to the course learning about what you do and customising the course and case studies based on your own procedures. To talk about custom training call 01462 713313.