ISO 27875:2019

INTERNATIONAL ISO
STANDARD 27875
Second edition
2019-02
Space systems — Re-entry risk
management for unmanned spacecraft
and launch vehicle orbital stages
Systèmes spatiaux — Gestion du risque de la rentrée pour les étapes
orbitales des véhicules spatiaux non habités et des lanceurs spatiaux
Reference number
©
ISO 2019
© ISO 2019
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ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Re-entry risk management . 2
4.1 General . 2
4.2 Re-entry safety programme . 2
4.3 Re-entry safety oversight and management . 2
4.4 Re-entry risk assessment and mitigation plan . 2
4.4.1 Preparation of the plan . . 2
4.4.2 Authorization of the plan . 3
4.5 Re-entry risk management concept . 3
5 Risk assessment for the case of natural re-entry . 3
5.1 General . 3
5.2 Identification of safety requirements . 4
5.2.1 Identification of requirements . 4
5.2.2 Risk assessment plan . 4
5.3 Identification of standardized process and resources for analysis . 4
5.4 Identification of system/mission dependent parameters . 5
5.5 Estimation of risk in the case of natural re-entry . 5
5.5.1 Estimation of the number of casualties. 5
5.5.2 Estimation and assessment of casualty risk . 6
5.6 Assessment of environmental risk. 6
5.7 Risk decision and actions . 7
5.7.1 Acceptance of risk or suggestion for risk reduction . 7
5.7.2 Consideration with other risk, if required . 7
6 Risk-reduction measures . 7
6.1 General . 7
6.2 Design measures to reduce re-entry survivability . 8
6.3 Controlled re-entry. 8
7 Planning, design and operation of controlled re-entry . 8
7.1 General . 8
7.2 Identification of requirements . 8
7.3 Planning of the controlled re-entry . 9
7.3.1 Landing location and area . 9
7.3.2 Design features for controlled re-entry . 9
7.4 Risk assessment for controlled re-entry .10
7.4.1 Risk assessment method .10
7.4.2 In case of non-conformance .10
7.5 Notification .10
7.5.1 Normal plan.10
7.5.2 Contingency plan .10
7.6 Post re-entry activities .11
Annex A (informative) Contents of the re-entry risk assessment and mitigation plan .12
Annex B (informative) The risk management process .15
Annex C (informative) Calculation of expected number of casualties .19
Bibliography .23
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
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electrotechnical standardization.
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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).
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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.
This second edition cancels and replaces the first edition (ISO 27875:2010) which has been technically
revised. It also incorporates the Amendment ISO 27875/Amd1: 2016. The main changes compared to
the previous edition are as follows:
— revised 6.2;
— a Note 1 to entry was added to the definition of Ec;
— long sentences were divided into multiple sub-clauses with each sub-clause containing just one
requirement.
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.
iv © ISO 2019 – All rights reserved

Introduction
According to international treaties, the “launching state” is liable for damage or injuries caused by
unmanned spacecraft and launch vehicle orbital stages that re-enter the Earth's atmosphere. In
addition, commercial operators are subject to the national safety regulations or laws of the launching
country that relate to the re-entry of spacecraft and launch vehicle orbital stages. To minimise damage
and injuries from re-entering spacecraft and launch vehicle orbital stages, all parties (i.e., developers,
manufacturers, space service providers, satellite operators, and launch service providers) should take
preventive measures during design and operations.
INTERNATIONAL STANDARD ISO 27875:2019(E)
Space systems — Re-entry risk management for unmanned
spacecraft and launch vehicle orbital stages
1 Scope
This document provides a framework with which to assess, reduce, and control the potential risks that
spacecraft and launch vehicle orbital stages (referred to hereinafter as “space vehicles”) pose to people
and the environment when those space vehicles re-enter the Earth's atmosphere and impact the Earth’s
surface. It is intended to be applied to the planning, design, and review of space vehicle missions for
which controlled or uncontrolled re-entry is inevitable.
This document is applicable to following objects in assessing their risk to the ground:
a) objects re-entering from orbit in conformance with ISO 24113;
b) launch vehicles (including payloads, other objects separated during the ascent phase, etc.) that are
mentioned in flight safety activities under ISO 14620-2[ ]; and
c) interplanetary spacecraft returning to Earth.
This document complements ISO 14620-1 and ISO 17666.
This document is not applicable to spacecraft containing nuclear power sources[ ].
NOTE 1 This document does not apply to Space Transportation Systems with wings and control functions
intended for targeted landing.
NOTE 2 Useful background information for this document is available in ISO 24113.
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
...