ISO TR 18147-2014 PDF

Full title and description

Space environment (natural and artificial) — Method of the solar energetic protons fluences and peak fluxes determination. This technical report defines a methodology and base tables for calculating solar energetic proton (SEP) fluences and peak fluxes for near‑Earth and heliospheric missions, using a probabilistic approach to support assessment of radiation effects on materials, hardware and biological systems.

Abstract

ISO/TR 18147:2014 provides a method to establish differential energy spectra and basic fluences/peak fluxes for solar energetic protons (covering a wide energy range) for use in the space environment (beyond the magnetosphere and for near‑Earth orbits when magnetospheric penetration is considered). The method is probabilistic and intended for specialists who determine radiation conditions for spacecraft and related systems.

General information

• Status: Published.
• Publication date: April 2014 (First edition).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 49.140 — Space systems and operations.
• Edition / version: Edition 1 (2014).
• Number of pages: 22 (ISO published document).

Scope

The report establishes procedures and base tables for calculating SEP fluences and peak fluxes (differential energy spectra across the relevant proton energy ranges) for missions of any duration under varying solar activity. It covers determination in near‑Earth space and, with appropriate considerations, throughout the heliosphere; it also addresses how magnetospheric penetration affects on‑orbit values. Calculations are presented as probabilistic estimates tied to different confidence levels, intended to support design, testing and risk assessment for space hardware and human spaceflight.

Key topics and requirements

• Methodology for deriving differential energy spectra for solar energetic protons (fluence and peak flux).
• Base tables and calculation technique for probabilistic determination of SEP fluences and peak fluxes.
• Guidance on applying the method for near‑Earth orbits and broader heliospheric environments, including magnetospheric effects.
• Informative annexes describing methodical principles and comparison of model and experimental data.

Typical use and users

Used by spacecraft systems engineers, radiation environment modelers, mission planners, payload designers, test laboratories and researchers assessing radiation risks to electronics, materials, solar arrays and crewed systems. The report supports selection of shielding, radiation-hardened components, and verification/testing approaches where SEP exposure is a design driver.

Related standards

This technical report is part of the ISO space environment deliverables under ISO/TC 20/SC 14 and is complementary to other ISO documents covering space environment and radiation (for example ISO process and procedural standards on solar irradiances and space environment simulation) and related technical specifications for space systems and testing produced by ISO/TC 20/SC 14. Users commonly consult the ISO/TC 20/SC 14 catalogue for adjacent documents (e.g., space environment and simulation TRs and TSs).

Keywords

solar energetic particles; SEP; solar protons; proton fluence; peak flux; space environment; probabilistic radiation models; spacecraft radiation assessment; ISO/TR 18147:2014.

FAQ

Q: What is this standard?

A: ISO/TR 18147:2014 is a technical report from ISO that specifies a method for determining solar energetic proton fluences and peak fluxes for space environments, presented as probabilistic estimates and supported by base tables and calculation techniques.

Q: What does it cover?

A: It covers the derivation of differential energy spectra for SEP fluences and peak fluxes over relevant proton energy ranges, methods for calculating values for missions of varying duration and solar activity, and guidance on applying magnetospheric penetration effects for near‑Earth orbits. It includes informative annexes on method principles and model/experiment comparisons.

Q: Who typically uses it?

A: Spacecraft and mission system engineers, radiation analysts, test laboratories, researchers, and those responsible for radiation mitigation and shielding design use this report to inform design choices and risk assessments.

Q: Is it current or superseded?

A: This document was published in April 2014 as Edition 1 and is listed as published by ISO; there is no public record on the ISO catalogue indicating it has been withdrawn or superseded as of the ISO entry. Users should check the ISO catalogue or national standards bodies for any updates or confirmations before use.

Q: Is it part of a series?

A: It belongs to the family of ISO deliverables addressing the space environment and space systems under ISO/TC 20/SC 14; while not numbered as a multi‑part series itself, it complements other ISO space environment TRs and TSs produced by the same subcommittee.

Q: What are the key keywords?

A: Solar energetic particles (SEP), protons, fluence, peak flux, space environment, radiation assessment, probabilistic modelling, spacecraft design.