1、Lessons Learned Entry: 0142Lesson Info:a71 Lesson Number: 0142a71 Lesson Date: 1992-10-05a71 Submitting Organization: KSCa71 Submitted by: Lisa L. MusgraveSubject: 540A Industrial Oxygen (O2) Analyzer Monitoring Description of Driving Event: The 540A industrial oxygen analyzer continuously monitors
2、the oxygen content from samples of atmosphere. Monitored areas include the orbiter processing facility, vertical assembly building, mobile launch platform, and the pads. When the oxygen level in these areas drops to an unsafe level of 19.5% or less, an audible/visible alarm is activated to warn pers
3、onnel to evacuate the area. The oxygen analyzer has a sensing circuit which relays data to a supervisory box assembly which triggers the battery box assembly if an oxygen deficiency is detected. The battery box assembly supplies power to the warning beacon and sends a read out to the complex center
4、console C-2 (in the launch control center). A component failure within the oxygen analyzer due to fatigue/shorting may cause an erroneous high output signal when the oxygen level is below 19.5%, resulting in no alarm warning. Personnel may enter/work in the area, unaware of the low oxygen level, and
5、 become asphyxiated.Lesson(s) Learned: An oxygen analyzer system failure may cause personnel to unknowingly enter or work in an oxygen deficient atmosphere, resulting in asphyxiation/death.Recommendation(s): Provide periodic 02 analyzer calibration checks and introduce oxygen-free gas into sample po
6、rts to verify proper operation of direct output module.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): N/AAdditional Key Phrase(s): a71 Facilitie
7、sa71 Ground Operationsa71 Logisticsa71 Occupational Healtha71 Risk Management/AssessmentAdditional Info: Approval Info: a71 Approval Date: 1994-06-03a71 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-,-,-
