1、Lessons Learned Entry: 1719Lesson Info:a71 Lesson Number: 1719a71 Lesson Date: 2006-03-14a71 Submitting Organization: JSCa71 Submitted by: Ron Montaguea71 POC Name: SheliaPowella71 POC Email: shelia.k.powellnasa.gova71 POC Phone: 281-483-3142Subject: Need for Change Analysis to Adjust Scope/Adequacy
2、 of Procedural Cautions and Warnings Abstract: Unexplained anomalies in hazardous environments must be regarded as imminent hazards until a risk assessment is made.Description of Driving Event: An electrician suffered burns from an electrical arc/blast when a pre-existing condition in a power distri
3、bution panel ultimately led to a ground fault in a 3-phase 480-volt power supply. The pre-existing condition was believed to be an access panel fastener that had penetrated conductor insulation. The history of circuit breaker trips despite repeated trouble shooting suggested that there was an unstab
4、le system with an unexplained anomaly. This requires that the entire system be considered suspect form a safety standpoint and normal work practices would not apply. However, it is also recognized that the anomaly does not conclusively indicate a problem with a pre-existing condition in the upstream
5、 main distribution panel; all reasonable scenarios suggest otherwise. The anomaly and the pre-existing condition are likely unrelated. If there were any reasonable relationship, such recognition would have resulted in management intervention and cautions and warnings. A hazard analysis, inspections
6、or findings during preventive maintenance might have identified this pre-existing condition.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Lesson(s) Learned: Change analysis is need to verify the adequacy of cautions and warnings as originally docum
7、ented in hazardous proceduresRecommendation(s): 1. Job hazard analyses are often needed for specific tasks. a. Identify fault energies available at the equipment (see the National Electrical Codes for guidelines). b. Maintain the arc flash energy zone to minimize injury. c. Provide training on the p
8、ersonal protective equipment required when working in these zones. d. Design or specify high side / low side compartment barriers. 2. Incorporate inspection criteria in preventive maintenance and configuration management work orders. 3. Follow procedures in sequence as written. Assure that as tasks
9、are revised in the field that those revisions become lessons learned and incorporated in future procedures. 4. Ensure that procedures and referenced materials are available to employees at the job site.Evidence of Recurrence Control Effectiveness: NoneDocuments Related to Lesson: N/AMission Director
10、ate(s): N/AAdditional Key Phrase(s): a71 Program Management.a71 Program Management.Business processesa71 Program Management.Communications between different offices and contractor personnela71 Program Management.Contractor relationshipsa71 Program Management.Risk managementa71 Manufacturing and Asse
11、mblyProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-a71 Additional Categories.a71 Additional Categories.Configuration Managementa71 Additional Categories.Emergency Preparednessa71 Additional Categories.Energya71 Additional Categories.Facilitiesa71 Ad
12、ditional Categories.Fire Protectiona71 Additional Categories.Human Factorsa71 Additional Categories.Industrial Operationsa71 Additional Categories.Parts, Materials, & Processesa71 Additional Categories.Personal Protective Equipmenta71 Additional Categories.Policy & Planninga71 Additional Categories.
13、Procurement, Small Business & Industrial Relationsa71 Additional Categories.Risk Management/AssessmentAdditional Info: a71 Project: N/AApproval Info: a71 Approval Date: 2006-06-30a71 Approval Name: tmasona71 Approval Organization: HQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
