Practical Examples of a New Approach to Creating Clear Operational Safety Cases

Jane Fenn; Richard David Hawkins; Mark Nicholson

Practical Examples of a New Approach to Creating Clear Operational Safety Cases

Jane Fenn, Richard David Hawkins, Mark Nicholson

Computer Science

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

Abstract

The concept of an ‘Operational Claim Point’, (OCP), has recently been proposed as a mechanism for improving the structuring and clarity of Operational Safety Cases. OCPs provide a mechanism by which arguments and evidence in the operational domain can be explicitly connected to design-time risk arguments. This gives rise to a number of benefits: ensuring that system operators are able to focus on just the operational aspects of the safety case relevant to them (hiding irrelevant and potentially confusing design details); making sure that, at the same time, the crucial relationship between the operational safety case and the design-time risk argument is explicitly documented and maintained (helping operators to better un-derstand the safety impact of their work); and allowing design-time safety engineers to specify, in the risk argument, safety claims relating to system operation. We provide worked examples of how OCPs can be used in practice. Through these ex-amples we explore some of the challenges in creating operational safety cases, in-cluding the link to the operational Safety Management System. We consider the impact of evidence that becomes apparent during operation, indicating unaccepta-ble risk levels, and argument and evidence that may change depending on the spe-cific choices of different operators of the same system.

Original language	English
Title of host publication	Safety Critical Systems Symposium (SSS '25)
Publication status	Published - 6 Feb 2025

Bibliographical note

This is an author-produced version of the published paper. Uploaded with permission of the publisher/copyright holder. Further copying may not be permitted; contact the publisher for details

Access to Document

Jane Fenn - JLF-RH-MN-SSS '25 paper-submitted
This is an author-produced version of the published paper. Uploaded with permission of the publisher/copyright holder. Further copying may not be permitted; contact the publisher for details
Accepted author manuscript, 790 KBLicence: CC BY

Cite this

@inproceedings{9197fed7fa284b24968b749f9034c556,

title = "Practical Examples of a New Approach to Creating Clear Operational Safety Cases",

abstract = "The concept of an {\textquoteleft}Operational Claim Point{\textquoteright}, (OCP), has recently been proposed as a mechanism for improving the structuring and clarity of Operational Safety Cases. OCPs provide a mechanism by which arguments and evidence in the operational domain can be explicitly connected to design-time risk arguments. This gives rise to a number of benefits: ensuring that system operators are able to focus on just the operational aspects of the safety case relevant to them (hiding irrelevant and potentially confusing design details); making sure that, at the same time, the crucial relationship between the operational safety case and the design-time risk argument is explicitly documented and maintained (helping operators to better un-derstand the safety impact of their work); and allowing design-time safety engineers to specify, in the risk argument, safety claims relating to system operation. We provide worked examples of how OCPs can be used in practice. Through these ex-amples we explore some of the challenges in creating operational safety cases, in-cluding the link to the operational Safety Management System. We consider the impact of evidence that becomes apparent during operation, indicating unaccepta-ble risk levels, and argument and evidence that may change depending on the spe-cific choices of different operators of the same system.",

author = "Jane Fenn and Hawkins, {Richard David} and Mark Nicholson",

note = "This is an author-produced version of the published paper. Uploaded with permission of the publisher/copyright holder. Further copying may not be permitted; contact the publisher for details",

year = "2025",

month = feb,

day = "6",

language = "English",

booktitle = "Safety Critical Systems Symposium (SSS '25)",

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T1 - Practical Examples of a New Approach to Creating Clear Operational Safety Cases

AU - Fenn, Jane

AU - Hawkins, Richard David

AU - Nicholson, Mark

N1 - This is an author-produced version of the published paper. Uploaded with permission of the publisher/copyright holder. Further copying may not be permitted; contact the publisher for details

PY - 2025/2/6

Y1 - 2025/2/6

N2 - The concept of an ‘Operational Claim Point’, (OCP), has recently been proposed as a mechanism for improving the structuring and clarity of Operational Safety Cases. OCPs provide a mechanism by which arguments and evidence in the operational domain can be explicitly connected to design-time risk arguments. This gives rise to a number of benefits: ensuring that system operators are able to focus on just the operational aspects of the safety case relevant to them (hiding irrelevant and potentially confusing design details); making sure that, at the same time, the crucial relationship between the operational safety case and the design-time risk argument is explicitly documented and maintained (helping operators to better un-derstand the safety impact of their work); and allowing design-time safety engineers to specify, in the risk argument, safety claims relating to system operation. We provide worked examples of how OCPs can be used in practice. Through these ex-amples we explore some of the challenges in creating operational safety cases, in-cluding the link to the operational Safety Management System. We consider the impact of evidence that becomes apparent during operation, indicating unaccepta-ble risk levels, and argument and evidence that may change depending on the spe-cific choices of different operators of the same system.

AB - The concept of an ‘Operational Claim Point’, (OCP), has recently been proposed as a mechanism for improving the structuring and clarity of Operational Safety Cases. OCPs provide a mechanism by which arguments and evidence in the operational domain can be explicitly connected to design-time risk arguments. This gives rise to a number of benefits: ensuring that system operators are able to focus on just the operational aspects of the safety case relevant to them (hiding irrelevant and potentially confusing design details); making sure that, at the same time, the crucial relationship between the operational safety case and the design-time risk argument is explicitly documented and maintained (helping operators to better un-derstand the safety impact of their work); and allowing design-time safety engineers to specify, in the risk argument, safety claims relating to system operation. We provide worked examples of how OCPs can be used in practice. Through these ex-amples we explore some of the challenges in creating operational safety cases, in-cluding the link to the operational Safety Management System. We consider the impact of evidence that becomes apparent during operation, indicating unaccepta-ble risk levels, and argument and evidence that may change depending on the spe-cific choices of different operators of the same system.

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BT - Safety Critical Systems Symposium (SSS '25)

ER -