ISO/TS 18667:2018

TECHNICAL ISO/TS
SPECIFICATION 18667
First edition
2018-02
Space systems — Capability-based
Safety, Dependability, and Quality
Assurance (SD&QA) programme
management
Systèmes spatiaux — Management de programmes de sécurité, de
sûreté de fonctionnement et d'assurance de la qualité (SD&QA), axé
sur les capacités
Reference number
©
ISO 2018
© ISO 2018
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ii © ISO 2018 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 1
3.1 Terms and definitions . 2
3.2 Abbreviated terms . 4
4 Objectives, policy and principles — General . 5
4.1 Objectives. 5
4.2 Policy . 5
4.3 Principles . 6
5 Instructions . 9
5.1 General . 9
5.2 Authorize SD&QA programme . 9
5.2.1 General. 9
5.2.2 Safety programme .10
5.2.3 Dependability programme .10
5.2.4 Quality Assurance (QA) programme .10
5.2.5 Assign qualified managers, leads, engineers, and technicians to
SD&QA programme.10
5.2.6 Continuously improve the SD&QA process .10
5.3 Define/identify, assess, and flow down the SD&QA requirements .10
5.3.1 Flow down the essential SD&QA requirements .11
5.3.2 Conflicting SD&QA requirements disposition criteria .12
5.4 Planning the SD&QA programme .12
5.4.1 General.12
5.4.2 Select SD&QA processes based on Product Unit-Value/Criticality Categories .16
5.4.3 Define SD&QA process implementation phasing based on systems
engineering life cycle phases/milestones .16
5.4.4 Identify the SD&QA guidance sources .19
5.4.5 Establish the Technical Performance Metrics .19
5.5 Coordinate the SD&QA processes with other product assurance processes .19
5.5.1 General.19
5.5.2 Coordinate Project’s and Subcontractor’s SD&QA Activities .19
5.5.3 Establish, utilize, and maintain a project SD&QA database system .20
5.6 Apply engineering and evaluation methods to identify system and process deficiencies .20
5.6.1 General.20
5.6.2 Define the system failure criteria and identify failure modes .20
5.6.3 Assess maturity of key input data, constraints, ground rules, and
analytical assumptions .22
5.7 SD&QA risk assessment and control .23
5.7.1 Integrate SD&QA with programme-wide technical risk management processes 23
5.7.2 SD&QA risk management responsibilities .23
5.7.3 SD&QA Programme Self-Inspections.24
5.7.4 SD&QA risk identification .25
5.7.5 Qualitative SD&QA risk likelihood assessment .27
5.7.6 Quantitative SD&QA risk likelihood assessment .30
5.7.7 SD&QA risk mitigation assessment .30
5.7.8 SD&QA risk tracking .30
5.7.9 SD&QA risk level assessment .31
5.7.10 Separate ESOH/system safety risk management .32
5.7.11 Present SD&QA risk status using a single risk matrix format .32
5.7.12 Perform structured SD&QA reviews .35
5.7.13 Apply SD&QA lessons learned .36
5.8 Verify SD&QA requirements are met .36
Annex A (informative) Fundamental SD&QA Processes .37
Annex B (informative) Capability-based Safety, Dependability and Quality Assurance
Programme tailoring requirements template .39
Annex C (informative) Safety, Dependability and Quality Assurance (SD&QA) programme
and Process Definitions .44
Annex D (informative) Space systems safety-critical and mission-critical unacceptable
conditions checklist (Cont.) .63
Bibliography .66
iv © ISO 2018 – All rights reserved

Foreword
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URL: www .iso .org/ iso/ foreword .html
This document was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles,
Subcommittee SC 14, Space systems and operations.
Introduction
This document is intended for use in the engineering community.
The terms Safety, Dependability, and Quality Assurance (SD&QA) are often used interchangeably, but
they have very different meanings. Safety is the system state with acceptable levels of risk for conditions
that can cause death, injury, occupational illness, damage to or loss of equipment or property, or
damage to the environment. Dependability is the ability of an item or system to perform as and when
required. Quality Assurance is the part of quality management focused on providing confidence that
quality requirements are fulfilled.
This document defines the “what to do’s” at depths that facilitate consistency in planning and
implementing SD&QA programme which identify, assess, and eliminate or mitigate technical risks
using levels of effort commensurate with the product’s unit-value/criticality and systems engineering
life cycle data content/maturity.
The fundamental building blocks of the capability-based SD&QA programme consists of the SD&QA
processes identified in Annex A and described in Annex C. The fundamental SD&QA processes are
grouped programmatically according to separate SD&QA domains, and functionally according to
documented management, engineering, and testing approaches. Annex B defines the tiered criteria
used for rating the SD&QA risk management capability of existing SD&QA programme or f
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