1、Lessons Learned Entry: 0146Lesson Info:a71 Lesson Number: 0146a71 Lesson Date: 1992-10-02a71 Submitting Organization: KSCa71 Submitted by: David PenningtonSubject: Fuel and Oxidizer Storage Tank Relief Valves. Description of Driving Event: The present method of annual calibration of fuel and oxidize
2、r storage area relief valves involves removal of the valves, thus opening the tank to the atmosphere. Large amounts of toxic vapor may be released. During one operation for the N2O4 storage tank relief valve, a greater than expected quantity of N2O4 vapor released (28 gallons compared to the one gal
3、lon expected). The extensive dispersion of the vapor cloud exceeded the predesignated clear area of 700 ft. Downwind. Also, several personnel were exposed to the vapor due to unrelated circumstances.Lesson(s) Learned: Lack of relief valve isolation has resulted in excessive toxic vapor releases to t
4、he environment.Recommendation(s): Install a dual relief valve system with a 3-way 2-position valve and isolation valves with aspirator access ports.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: Provided by IHSNot for ResaleNo reproduction or networking permitted witho
5、ut license from IHS-,-,-N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Facilitiesa71 Ground Equipmenta71 Hardwarea71 Hazardous/Toxic Waste/MaterialsAdditional Info: Approval Info: a71 Approval Date: 1994-06-06a71 Approval Name: James G. Klinea71 Approval Organization: KSC/HEIa71 Approval Phone Number: 407-867-7614Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
