1、Best Practices Entry: Best Practice Info:a71 Committee Approval Date: 2000-03-01a71 Center Point of Contact: KSCa71 Submitted by: Wil HarkinsSubject: Fail Safe Firex/Deluge System Practice: Incorporation of prudent design techniques results in reliable Firex/Deluge System Design Practice for Elimina
2、tion of Single Point Failures and Unsolicited Operation.Programs that Certify Usage: This practice has been used on the Space Shuttle Program, Ground Support Equipment, KSC Launch Complex 39 Pad B Payload Changeout Room Firex/Deluge System KSC Mobile Launch Platform (-1, -2, -3) Hydrazine Service Ar
3、ea Firex/Deluge.Center to Contact for Information: KSCImplementation Method: This Lesson Learned is based on Reliability Practice number GSE-3002 from NASA Technical Memorandum 4322A, NASA Reliability Preferred Practices for Design and Test.Benefit:This design standard incorporated a fail safe pract
4、ice that prevents the two potential failures inherent to a water protection system:1. Lack of water flow when required2. Inadvertent water flow when not required.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Implementation Method:This design implem
5、ents a practice which might be considered as excessive due to the added expense of the additional water valves and their associated controls. However, applied in an appropriate situation this configuration could prove to be very cost effective. The appropriate application for this design would be wh
6、ere the protected materials are susceptible to ruination from water damage.The loss incurred from fire damage and the lack of fire extinguishing capability is well understood. This configuration provides added security to the user that the system will be available when required. Not as evident is th
7、e susceptibility to damage as a result of an inadvertent activation or failure. This arrangement provides the security that a single failure will not result in a water deluge potentially destroying the property it was designed to protect.Technical Rationale:The basis for this configuration is the se
8、ries-parallel arrangement of the water valves shown in Figure 1. An adequate flow of water should be available to the user through any of the paths involving the “ARM“ and “ACTIVATE“ valves, i.e. all that is required is one “ARM“ valve and one “ACTIVATE“ valve to open (see figure 1 to show available
9、 water paths). The valves should be pneumatically or hydraulically controlled through electrically positioned solenoid valves. Each water valve should have its own controlling solenoid valve. The “ARM“ solenoid valves should be controlled open by two parallel redundant controlling devices (relays, p
10、rogrammable logic controllers, etc.) and the “ACTIVATE“ solenoid valves should be controlled open by two other parallel redundant controlling devices. Local and remote valve actuation should be provided with separate “ARM“ and “ACTIVATE“ switches. These arrangements insure that a single failure will
11、 not prevent water flow when required or initiate water flow when not desired.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-refer to D descriptionD References:1. KSC-STD-F-0004C: Standard for Fire Protection Design for Facilities, John F. Kennedy S
12、pace Center, NASA.2. SAA09SY03B-001: System Assurance Analysis of the Pad Water System at LC-39 Pad B & MLP-1, -2.3. 79K40019: LOA Facility Water Pad B SMS/EMCD.4. 80K55529: LOA Facility Water MLP 1, 2, & 3 SMS/EMCD.Impact of Non-Practice: This system serves two purposes. It prevents a single failur
13、e from rendering the FIREX system inoperative and helps prevent the occurrence of an inadvertent operation of the FIREX Deluge System.Related Practices: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Additional Info: Approval Info: a71 Approval Date: 2000-03-01a71 Approval Name: Eric Raynora71 Approval Organization: QSa71 Approval Phone Number: 202-358-4738Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
