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Lecture 6: Design Guidelines

Safety Philosophies, Hazard Control, Safety Verification

NASA Preferred Technical Standards

The NASA JSC Payload Safety Home Page (Payload Safety Review Panel).

Interpretations of NSTS Payload Safety Requirements NSTS 18798A

Or check these Goddard Copies:

Safety Policies and Requirements NSTS1700.7B (Shuttle) and Addendum (ISS)

Implementation Procedures For NSTS Payload System Safety Requirements NSTS 13830B

GUIDELINES FOR THE PREPARATION OF PAYLOAD FLIGHT SAFETY DATA PACKAGES AND HAZARD REPORTS NSTS 26943

Revision C Payload Verification NSTS 14046

Other information contained : Hazard Definitions, Generic Hazard Reports (taken directly from NSTS 26943), Hazard Analysis Techniques, Hazard groupings, subsystem hazards. All information which appears in this system is taken from NASA Safety related documents.


Critical Hazard                    damage to equipment, non-disabling injury, requires unscheduled safing of orbiter, affects operations

                                                      no single failure should result in a critical hazard ==> 2 controls (i.e., redundant) to prevent critical hazard

Catastrophic Hazard:          disabling / fatal personal injury, loss or orbiter

                                                      no combination of two failures should result in a catastrophic hazard ==> 3 controls (i.e., dual redundant) to

                                                      prevent critical hazard

Failure Tolerance:               basic safety requirement; tolerate minimum number of CREDIBLE failures

                                                      single tolerant = 2 independent controls

Design for Minimum Risk:  adequate factors of safety: structures, pressure vessels, pressure lines, fittings, pyrotechnics, mechanisms,

                                                       materials compatibility, flammability

Special Consideration:

Pressure Systems         Sealed Container, Pressure Vessel, Energy Content, MDP / MOP

Radiation:                     Ionizing radiation, electromagnetic radiation (emission, susceptibility)

Hazardous Materials:   No release, containment, materials compatibility

Chemical Release

Flammable Materials

Batteries                       JSC 20793 - Manned Space Vehicle Battery Safety Handbook, 9/85

Hazard Report                        critical / catastrophic hazard

JSC Form 1230 - Flight Payload Standardized Hazard Control Report, 11/98

Mechanical Hazard      sharp edges, protrusion

Thermal Hazard           high / low temperatures, touch / exhaust / dew temperature (>4C --- < 45C)

Electric Hazard             electric shock                                      

Fire Protection

Safety Review Process (NSTS13830)

(Payload Safety Review and Data Submittal Requirements For Payloads Using the  Space Shuttle And  International Space Station, July 1998)

Phase 0                       Phase 0 is held during the concept phase or at the start of payload design

                                              Payload description, identify potential hazards 

Phase I                        Phase I is near the Preliminary Design Review (PDR)

                                              Hazards Identified, identify potential hazard controls

Phase II                       Phase II is near the Critical Design Review (CDR)

                                              Hazard Controls Finalized, start verifications

Phase III                      Phase III is associated with completion of payload safety verifications

                                              Ideally: safety verifications complete

Phase III delta              minor modifications to existing hardware

Reflight Assessment     assess validity of existing verifications for un-changed payload

Transition of NSTS Payloads to ISS: longer exposure / life time, modified rules / limits

Verification Tracking Log    track open verifications between Phase III and Flight

The flight and ground phase III completion requirements restated below are in the current version of NSTS 1700.7 (flight; Ground KHB1700.7) and NSTS 1700.7 ISS Addendum (flight) and apply to all payloads. 

The JSC and KSC Phase III safety review and ground safety certification must be completed 30 days prior to delivery of the payload, ASE, and GSE to the launch site


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