ISO 26871:2020

INTERNATIONAL ISO
STANDARD 26871
Second edition
2020-10
Space systems — Explosive systems
and devices
Systèmes spaciaux — Dispositifs et equipements explosifs
Reference number
ISO 26871:2020(E)
©
ISO 2020

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ISO 26871:2020(E)

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© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ISO 26871:2020(E)

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, abbreviated terms and symbols . 1
3.1 Terms and definitions . 1
3.2 Abbreviated terms . 8
3.3 Symbols .10
4 Requirements .10
4.1 General .10
4.1.1 Background information .10
4.1.2 Overview .10
4.1.3 Applicability .11
4.1.4 Properties .11
4.2 Design .11
4.2.1 General.11
4.2.2 Debris requirements.12
4.2.3 Reliability and confidence levels .13
4.2.4 Performance .13
4.2.5 Wanted and unwanted response .13
4.2.6 Dimensioning .13
4.3 Mission .16
4.4 Functionality .16
4.5 Safety .17
4.5.1 General.17
4.5.2 Prevention of unintentional function .17
4.6 Survival and operational conditions .18
4.7 Interface requirements .19
4.7.1 General.19
4.7.2 Functional .19
4.7.3 Internal .19
4.7.4 External .20
4.8 Mechanical, electrical, and thermal requirements .20
4.8.1 Mechanical .20
4.8.2 Electrical .21
4.8.3 Thermal.24
4.8.4 Status check.25
4.9 Materials .26
4.10 Production lot .27
4.11 Non-explosive components and equipment .27
4.11.1 Connectors .27
4.11.2 Wiring .27
4.11.3 Shielding.28
4.11.4 Faraday cap .28
4.11.5 Safety cap.28
4.11.6 Power .28
4.11.7 Arm plug receptacle .29
4.11.8 Safe plug .29
4.11.9 Arm plug . .30
4.11.10 Test plug .30
4.11.11 Safe and arm device.30
4.11.12 Initiator harness connector .32
4.11.13 Initiator test substitute.32
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ISO 26871:2020(E)

4.12 Explosive components .32
4.12.1 General.32
4.12.2 Initiators, cartridges, detonators and packaged charges .33
4.12.3 Through-Bulkhead initiators .38
4.12.4 Integral initiator connectors .38
4.12.5 Transfer devices .39
4.12.6 Safe and arm devices containing explosive .40
4.12.7 Gas generators .41
4.12.8 Shaped charges.41
4.12.9 Expanding tube separation system .42
4.12.10 Distribution boxes .43
4.12.11 Explosive delays .44
4.13 Explosively actuated devices .45
4.13.1 General.45
4.13.2 Separation nuts and separation bolts .46
4.13.3 Pullers .47
4.13.4 Pushers (Thrusters) .48
4.13.5 Cutters .48
4.13.6 Pyro-valves .49
4.14 Items external to the flight equipment .50
4.14.1 GSE .50
4.14.2 Test equipment .50
4.14.3 Launch site .50
4.15 Verification .50
4.15.1 General.50
4.15.2 Inspection .50
4.15.3 Tests .51
4.15.4 Qualification and lot acceptance .53
4.16 Transport, facilities, handling and storage .56
4.16.1 General.56
4.16.2 Transport .56
4.16.3 Facilities . .57
4.16.4 Handling and storage .57
4.17 In-service .58
4.17.1 Information feedback .58
4.17.2 Launch site procedures .58
4.17.3 Monitoring .58
4.18 Product assurance .58
4.18.1 General.58
4.18.2 Dependability .58
4.18.3 Assembly integration and tests .58
4.19 Deliverables .59
Annex A (normative) Loads and factors of safety relationship .61
Annex B (normative) Factors of safety .63
Annex C (informative) Explosive component colour code .64
Annex D (informative) Component qualification test levels to be customized to the space
system considered .65
Annex E (informative) Product user manual (PUM/UM) — DRD .67
Annex F (informative) Safety data sheet .73
Bibliography .77
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ISO 26871:2020(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see 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.
This second edition cancels and replaces the first edition (ISO 26871:2012), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— simplification for some requirements;
— updating terminology;
— introduction of a paragraph about debris issues.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
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ISO 26871:2020(E)

Introduction
0.1 Background
The evolution of this document is motivated by changes inputted by the last issue of 2 main mother
[1],[2]
documents .
0.2 Tailoring
This document may be tailored, by the contractor, in consultation with the procuring authority, for the
specific characteristics and constraints of a space project.
Tailoring is a process by which individual requirements or specifications, standards, and related
documents are evaluated and made applicable to a specific program or project by selection, and in some
cases, modification and addition (e.g., for manned spaceflight) of requirements in the standards.
However, the tailored requirements may achieve a level of verification equivalent to the baseline
described herein. Rationale for each tailored requirement may be established. If the requirements in
this document are not tailored by a contract, they stand as written.
This document will be updated and revised periodically, each five years as appropriate to incorporate
technological advances and innovations as well as lessons learned.
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INTERNATIONAL STANDARD ISO 26871:2020(E)
Space systems — Explosive systems and devices
IMPORTANT — The electronic file of this document contains colours which are considered to be
useful for the correct understanding of the document. Users should therefore consider printing
this document using a colour printer.
1 Scope
This document specifies criteria and requirements for the use of explosive systems and explosive
devices commonly used on spacecraft and other space products, including launch vehicles and space
vehicle systems. It addresses the aspects of design, analysis, verification, manufacturing, operations
and safety.
To the greatest extent possible, requirements from past and existing standards have been analyzed,
selected and tailored to be incorporated herein. In addition, the requirements herein include those
generated as a result of lessons learned from launch and space vehicle programs.
NOTE Specific requirements for man-rating are not addressed.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 14300-1, Space systems — Programme management — Part 1: Structuring of a project
ISO 24113, Space systems — Space debris mitigation requirements
3 Terms, definitions, abbreviated terms and symbols
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1.1
actuator
component (3.1.10) that performs the moving function of a mechanism
Note 1 to entry: An actuator can be either an electric motor, or any other mechanical (e.g. spring) or electric
component or part providing the torque or force for the motion of the mechanism.
3.1.2
all-fire level
lowest level of the fire stimulus (including rise time, shape, duration), which results in initiation of a
first element (initiator) (3.1.36) within a specific reliability and confidence level as determined by test
and analysis
Note 1 to entry: The stimulus duration shall be compliant with the system.
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ISO 26871:2020(E)

Note 2 to entry: The test sequence should be carried out at the lowest temperature of the operating range.
Note 3 to entry: The probability of functioning should be equal to or better than 0,999 at the 95 % confidence level.
3.1.3
armed
status of an explosive subsystem, when all the safety devices have been disabled and which is able
to trigger
3.1.4
auto-ignition
spontaneous explosive reaction of energetic materials (3.1.19) in an explosively loaded device due to
exposure to environments or interfacing materials
3.1.5
bridgewire
resistive element incorporated into the first element (3.1.30) that converts electrical energy into heat or
shock to cause initiation of an explosive charge (3.1.8)
3.1.6
cartridge
explosive device designed to produce pressure for performing a mechanical function or actuate a
mechanical device
Note 1 to entry: A cartridge is called an initiator (3.1.36) if it is the first or only explosive element in an explosive
train (3.1.28).
3.1.7
catastrophic failure
failure which results in the loss of human life, mission or a major ground facility, or long-term
detrimental environmental effects
3.1.8
charge
explosive (3.1.23) loaded in a cartridge (3.1.6), detonator (3.1.14) or separate container for use in an
explosive device
3.1.9
closed bomb
fixed volume test chamber to measure output characteristics of pressure producing devices
3.1.10
component
set of materials, assembled according to defined and controlled processes, which cannot be disassembled
without destroying its capability and which performs a simple function that can be evaluated against
expected performance requirements
Note 1 to entry: The term “part” is preferred when referring to purely mechanical or explosive devices.
Note 2 to entry: The term “component” is preferred for EEE devices.
3.1.11
cook-off temperature
maximum temperature to which an explosively loaded device can be exposed for a period of one hour
without reaction
Note 1 to entry: The determination of the cook-off temperature is time and application dependent.
3.1.12
deflagration
chemical decomposition propagating through the explosive (3.1.23) at a subsonic velocity
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ISO 26871:2020(E)

3.1.13
detonation
chemical decomposition propagating through the explosive (3.1.23) at a supersonic velocity such that a
shock wave is generated
3.1.14
detonator
initiator (3.1.36) whose function is to transform external energy (e.g., mechanical, electrical, thermal)
directly into a shock wave strong enough to detonate a secondary high explosive (3.1.34)
Note 1 to entry: Detonators are generally used to effect detonation (3.1.13) transfers within explosive trains
(3.1.28).
3.1.15
duding
explosive charge (3.1.8) or component (3.1.10) that fails to fire or function upon receipt of the prescribed
initiating stimulus, after an external effect (human failure, manufacturing failure, environmental,
chemical, ageing, etc.)
3.1.16
electro-explosive device
EED
first element (3.1.
...