[Hallb-engineering] Fwd: Lesson Learned "Reliance on Older Documentation May Create Unreviewed Safety Question (USQ) - Pacific Northwest National Laboratory"
tilles at jlab.org
Wed Jun 1 06:08:30 EDT 2016
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From: "mbailey" <mbailey at jlab.org>
To: "mbailey" <mbailey at jlab.org>
Sent: Tuesday, May 31, 2016 4:00:06 PM
Subject: Lesson Learned "Reliance on Older Documentation May Create Unreviewed Safety Question (USQ) - Pacific Northwest National Laboratory"
Jefferson Lab Lessons Learned : Print Lesson
Reliance on Older Documentation May Create Unreviewed Safety Question (USQ) - Pacific Northwest National Laboratory
Statement of Lessons Learned
Review analytical documentation regularly to assure the methods used for calculating hazards are still relevant. Improved technology, changing conditions, and the level of rigor required may necessitate periodic reviews. Peer reviews and benchmarking other laboratories also provides another level of verification of safety analyses.
Discussion of Activities
During a review of the Radiochemical Processing Laboratory (RPL) Criticality Alarm System (CAS), questions were raised whether the High Level Radiochemistry Facility hot cells would adequately shield radiation from a criticality accident inside the cells. Questions were also raised on the supporting technical analysis which was last performed in 1998, and was considered outdated at the time of the review.
During a routine update of the RPL Documented Safety Analysis (DSA), questions were raised regarding the analysis of the CAS. Resulting discussions centered around whether the High Level Radiochemistry Facility hot cells could perform adequate shielding in the event of a criticality.
The technical analysis and computational modeling of the CAS detection coverage performed in 1998 determined that in the case of a criticality inside the hot cells, the event would not be detectable outside the cells due to the shielding properties of the concrete walls. At that time, the analyst also used engineering judgment, as was accepted practice, to determine that the windows and doors could provide adequate shielding, but they were not explicitly modeled like the walls were. Current capabilities in computer modeling and data analysis provide more capable and accurate evaluations.
As a result, the RPL building manager declared a Potential Inadequacy in the Safety Analysis. The subsequent Unreviewed Safety Question concluded that the DSA did not fully demonstrate adequate protection, detection, or response to a criticality accident inside the hot cells.
Going forward, safety analysis calculations supporting the RPL DSA will be reviewed every ten years at minimum to determine if methodology and results from the prior analysis remain valid.
Below are the consequences of the above event. They are provided for information and discussion purposes only.
As conditions change, so may the need for updated safety analyses, especially in high-risk, high-hazard environments. Technological advances, changes in requirements or conditions, or the level of rigor expected are triggers for reviewing documentation.
Technical Analysts and users of highly complex analytical documents:
-Determine appropriate periodicity. Complex reviews require extensive resources. Performing reviews of technical safety analyses too frequently is a drain on resources, while too infrequently creates risk.
-Identify changed conditions. Older analyses may become unreliable over time as a result of technological changes, changes in a facility's purpose, and updated requirements.
-Benchmark with other laboratories. Validate and verify assumptions by comparing with other similar facilities and requesting peer reviews.
JLab Preventive Measures
(Jefferson Lab's Subject Matter Expert has read and approved this lesson.)
Jefferson Lab's Document Control Program states that any "Document[s], that are necessary to ensure the effective planning, operation, and control of the lab's processes, are required to be controlled." This applies to all documents whether paper or electronic. Minimally controlled documents are:
- Periodically reviewed, by affected individuals or Subject Matter Experts, within a specified period of time (generally three years)
- Assigned a Document Owner responsible for maintenance and upkeep.
5/31/2016 2:08:02 PM by Bailey, Mary Jo
Submitted to those current in:
SAF101: Work Planning and Control Familiarization
Summary Lesson ID: 949
Doc ID: 2016-JLAB-949
Priority: Best Practice
Safety Related: NO
Originator: Bailey, Mary Jo
Issued: 5/31/2016 2:03:22 PM
Approved By: Bailey, Mary Jo
Approved On: 5/31/2016 2:08:02 PM
Contact: Reliance on Older Documentation May Create Unreviewed Safety Question (USQ) - Pacific Northwest National Laboratory
Queued Emails: 0
Sent Emails: 0
Viewings: 5 times Attachments
* DOE - CAR 1998.pdf
* Other: Work Planning and Communication,
* SAF101: Work Planning and Control Familiarization
* *Division Safety Officers (DSOs)
* *Safety Wardens
* *DOE Notification
* *ESH&Q Liaisons
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