컨설팅사업
SIL ASSESSMENT 수행,SRS 보고서 작성, SIL VERIFICATION 활동을 수행하는 것을 말합니다.
SIL Study 란?
대상 장치나 제품의 SIL(Safety Integrity Level;안전 무결성)상태를 확인 하기 위하여 SIL Assessment 를 수행하고 SRS(Safety Requirements Specification)보고서를 작성하고 SIL Verification 활동을 수행하는 것을 말합니다. SIL Study 방법은 LOPA(Layer of Protection analysis) 기법과 QRA(Quantitative Risk Analysis) 기법을 사용합니다.
LOPA 기법
QRA 기법
SRS 보고서 사례
SIS ID : |
SIS-x-L0XXX |
Service : xxxx Compressor Suction Scrubber LL level with Gas blow-by to drain seal drum and potential damage to drum |
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|---|---|---|---|---|---|---|
TAG # : |
0x-LLT-XXX |
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Required SIL : |
SIL 1 |
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Demand rate on SIS : |
Low demand |
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Test interval : |
1 year (to be confirmed by SIL verification) |
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Response Time : |
Refer to general Requirements |
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Method : |
De-energize to trip |
Safe state : Emergency Shutdown Valve (ESDV xxxx) between compressor suction scrubber and drain seal drum closed |
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Reset Type : |
Refer to general Requirements |
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Nuisance Trip Req’s : |
Refer to general Requirements |
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Special Diagnostics |
Transmitter usual diagnostic by PLC |
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Manual Shutdown |
Existing (manual control of ESDV xxxx) |
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Regulatory Req : |
Refer to general Requirements |
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MTTR : |
4 hours expected |
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Cause & Effect Diagram
|
EFFECT |
DESCRIPTION |
Close shutdown valve to drain drum |
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cause |
TAG |
07-ESDV-100 |
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Tag |
Description |
Alarm Tag |
Trip Point |
Notes |
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15-L010 |
Suction scrubber Low Low level |
15-AT-020 |
To be defined |
X |
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Hazard Control Principle
- Hazard elimination or inherent safety.
- Add-on safety devices(including M out of N structure)
- Provide Warning Devices”
- Develop Procedures and Training
- PFD(Probability of Failure per Demand)
- PFH(Probability of Failure per Hour)
| SIL | Low demand mode of operation(Average probability of failure to perform its design function on demand PFD) | High demand or continuous mode of operation(Probability of a dangerous failure per hour PFH) |
|---|---|---|
| 1 | 10-2 < PFD < 10-1 | 10-6 < PFH < 10-5 |
| 2 | 10-3 < PFD < 10-2 | 10-7 < PFH < 10-6 |
| 3 | 10-4 < PFD < 10-3 | 10-8 < PFH < 10-7 |
| 4 | 10-5 < PFD < 10-4 | 10-9 < PFH < 10-8 |
