1、 Public Lessons Learned Entry: 3336Lesson Info:a71 Lesson Number: 3336 a71 Lesson Date: 2010-05-27 a71 Submitting Organization: KSC a71 Submitted by: Annette Pitt Subject: Contamination Control Operational Maintenance Requirements and Specifications Document Requirements (OMRSD) Abstract: Contaminat
2、ion control facility environmental Operational Maintenance Requirements and Specifications Document (OMRSD) requirements were created before it was determined if they were even achievable during normal Orbiter processing at the Orbiter Processing Facility (OPF) high bays, and before it was determine
3、d if they were really warranted to protect the cleanliness level of the exposed Orbiter Payload Bay. After processing problem reports and waivers and/or exceptions to the OMRSD requirements for a number of missions, it was determined that violating the OMRSD requirements during normal processing was
4、 not causing any obvious detrimental effects to the flight hardware from a contamination control perspective. Therefore, the facility OMRSD requirements were determined to be no longer warranted and were deleted per RCN KV9009M2. Description of Driving Event: Early in the Shuttle Program, as contami
5、nation control was being recognized as a ”system,” OMRSD requirements were created for the OPF high bays. OMRSD requirements included specific temperature, relative humidity, and airborne particulate ranges that, if exceeded, resulted in an OMRSD violation. However, the normal processing activities
6、within the OPF high bays caused temporary out-of-specification environmental conditions that resulted in OMRSD violations numerous times during every Orbiter processing flow. Examples include opening facility doors to the outside environment for hardware entry, applying waterproofing on tiles, opera
7、ting overhead cranes, etc. Consequently, contamination control engineering was processing problem reports and waivers and/or exceptions to the OMRSD requirements for every mission. Eventually, it was realized that the normal Orbiter processing activities were not causing any obvious detriment to the
8、 vehicle from a contamination perspective, and therefore, the facility OMRSD requirements were no longer warranted. In addition, these OMRSD requirements were considered unrealistic for the type of operational activities needed to process the Orbiter. Where possible, mitigation efforts were implemen
9、ted to help reduce the generation or emission of contamination within the facility during certain operational activities (such as the incorporation of a captive air vent system that vented fumes from vacuum pumps and hydraulic aspirators outside of the facility). Lesson(s) Learned: Data collection d
10、uring a number of Orbiter processing flows was necessary to determine which facility contamination control OMRSD requirements were truly warranted to achieve and/or maintain the required flight hardware cleanliness level. Those OMRSD requirements that were not warranted were deleted in accordance wi
11、th RCN KV9009M2. Recommendation(s): Prior to creating facility contamination control environmental requirements, an evaluation of operational processing events/activities is necessary to assess the impact each event/activity has upon the exposed flight hardware and the facility environment. Evidence
12、 of Recurrence Control Effectiveness: N/A Documents Related to Lesson: NSTS 08171 Space Shuttle Operations and Maintenance Requirements and Specifications Document Mission Directorate(s): a71 Space Operations Provided by IHSNot for ResaleNo reproduction or networking permitted without license from I
13、HS-,-,-Additional Key Phrase(s): a71 1.Ground processing and manifesting a71 1.Level II/III requirements definition a71 1.Configuration control and data management Additional Info: a71 Project: Space Shuttle Program Approval Info: a71 Approval Date: 2010-12-03 a71 Approval Name: mbell a71 Approval Organization: HQ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
