1、Lessons Learned Entry: 1429Lesson Info:a71 Lesson Number: 1429a71 Lesson Date: 2002-04-11a71 Submitting Organization: LARCa71 Submitted by: Grant WatsonSubject: Potential Hazard from Cooling Tower Fans (2002) Abstract: A mishap where a cooling tower fan blade failed, has brought to light two importa
2、nt features of systems that contain rotating fans.Description of Driving Event: First, it is very important to have a containment screen, which will keep all the debris within the cooling tower. Consequently, debris did not become projectiles that could cause personal injury. A second important feat
3、ure is an operational vibration switch. The mishap investigation determined that the vibration switch was not working properly. Also, a review of several other cooling towers discovered inoperable vibration switches and switches that have been moved from periodic maintenance to the run-to-failure ma
4、intenance list.Lesson(s) Learned: 1. Ensure that all fans, whether in a small air conditioning unit or a large cooling tower, are properly guarded.2. In large systems, check the operational status of the vibration switches.3. Recommendation(s): Facility safety personnel need to verify that all fans,
5、 whether in a small air conditioning unit or a large cooling tower, are properly guarded. Also, large systems with vibration switches need to have the switchs operational status checked. Facility safety personnel should also ensure that vibration switches are being checked during annual maintenance
6、activities and have not been incorporated into the run-to-failure list. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa7
7、1 Sciencea71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Accident Investigationa71 Facilitiesa71 Ground Equipmenta71 Hardwarea71 Safety & Mission AssuranceAdditional Info: Approval Info: a71 Approval Date: 2004-06-04a71 Approval Name: Leslie Johnsona71 Approval Organization: LARCa71 Approval Phone Number: 757-864-9409Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
