Proof testing documentations

Requirements may be identified that will need to be addressed before the Management of Change procedure is complete. The second-level supervisor or department head is responsible to assure that suspended items within the PSSR are completed. Suspended items could include updating master drawings with the hand-corrected as built mark-ups, completing the documentation to set up proof tests or vessel inspections or other important items that should not necessarily delay a startup. 

It is important to document the results of the proof test and inspection for a record of what was found. There are no specific requirements for how long these results should be retained but generally a sufficient number are retained to allow for re-examination of previous results to see if there is a history of component failure. 

Solution Many manufacturers recommend proof test procedures for low demand safety instrumented system applications. The information is found in the safety manual. That document may be part of another manual or may be a separate document. Referring to the safety manual section of a pressure transmitter (Ref. 4), proof test options with associated coverage factors are given (Figure 7-2). The test titled Five Year Proof Test has a manual proof test coverage of 65%. The test titled Ten Year Proof Test has a manual proof test coverage of 99%. 

The following proof tests are recommended. Proof test results must be documented with corrective actions taken In the remote possibility that safety functionality is not correct. 

General Testing documentation Records of test completion dates (as-found/as-left) should be kept for the current and preceding test (at least one year). The identity of the person conducting the test and any unsatisfactory performance of the instrument is recorded. A history of poor reliability or proof-test failures requires action plans to correct. ... 

Bypass, start up override, and manual shutdown operational Well-documented proof test procedure Correct operation of SIS in utility failure, EMI, etc. 

To check and document proof test procedure and set proof test interval. Suitable measure towards this is necessary. 

Human aspect Consequence because of wrong proof test procedure Documentation of proof test activity Process safety response time consists of three components ... 

SIS documentation consistent with installed system SIFs perform as specified with invalid process variables Proper shutdown sequence activated Proper alarm and display by SIS Correct computations included in SIS Bypass and manual shutdown function correctly Reset of SIS functions as per SRS Proof test interval included in maintenance procedure Diagnostic alarm performs as required SIS performs as required in case of loss of power SIS goes to desired state on power resumption SIS EMC immunity as per SRS... 

Procedure documents and timings In an actual case the proof test procedure may not follow a single procedure document, but may be made up of different documents, for example, reference to other procedures. Also it may include procedures for testing different parts of SIS at different times. However, in all such cases, measures should be taken to ensure no failure modes or components are missed. It may include partial test procedures and full test procedures. 

Also the responsibility of each of these persons must be well defined. The approval process of verification and validation cannot be overestimated. So, those who wUl verify the documented proof test must be experienced as well as experts in this field, so that they can check and verify the adequacy of the tests. Also they must be well aware of what is demonstrated and what the object is. 

The ESS operation is passive most of the time. It monitors potentially unsafe conditions and responds to problems by shutting down some part of the plant. To maintain the low probability of failure on which the plant design is based, proof testing of the ESS is necessary. This should be carried out on a scheduled basis and carefully documented. 

Documentation for installation, use and maintenance Information on the SRECS shall be provided to Detailed description of the system and its subsystem including circuit diagrams. Correctly install the equipment. Use the equipment. Proof test requirements. Maintenance requirements. ... 

Documentation for recording safety audits and proof tests... 

Bypass and bypass reset functions are correct Manual shutdown systems operate correctly Proof test intervals documented in maintenance procedures Proof test intervals consistent with SIL calculations SIS documentation consistent with install/operate procedures Accuracy of calibration equipment consistent with resolution/accuracy of application... 

Documentation requirements (e.g., frequency of demands placed on SIF/SIS, procedures/methods/techniques, proof tests and inspections, test results, equipment identifiers down to the revision level, responsible persons/departments/organizations)... 

All formulas are to be written out by hand with the specific numbers in the right places on a sheet provided for the purpose, and the calculations are to be done by calculator. Caution Write the numbers exactly as printed, do not round any digits, or the quality assurance unit (a sort of corporate vice squad) will not approve the report out of fear that someone could have cheated. A validated program can be used. While an Excel spreadsheet as such needs no validation, a simple cell-formula calls for extensive tests and documentation and proof that the sheet is password protected against fraudulent manipulation. On top of that, the analyst s supervisor is required to confirm the calculation and sign off on... 

The requirements or prerequisites of the Basis Documents are fixed. Basis documents have targets they can be updated and are applicable over a longer time interval (e.g. standard operation procedures). Proof Documents contain proofs of operations and the details of the actual stock they are not changeable and are only valid for single incidents (e.g. test reports). 

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