National foreword

This British Standard is the UK implementation of ISO 23936‑3:2026.

The UK participation in its preparation was entrusted to Technical Committee PSE/17/67, ISO/TC 67 Management Committee.

A list of organizations represented on this committee can be obtained on request to its committee manager.

Contractual and legal considerations

This publication has been prepared in good faith, however no representation, warranty, assurance or undertaking (express or implied) is or will be made, and no responsibility or liability is or will be accepted by BSI in relation to the adequacy, accuracy, completeness or reasonableness of this publication. All and any such responsibility and liability is expressly disclaimed to the full extent permitted by the law.

This publication is provided as is, and is to be used at the recipient’s own risk.

The recipient is advised to consider seeking professional guidance with respect to its use of this publication.

This publication is not intended to constitute a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2026.

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 document 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).

ISO draws attention to the possibility that the implementation of this document may involve the use of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s) which may be required to implement this document. However, implementers are cautioned that this may not represent the latest information, which may be obtained from the patent database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.

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 67, Oil and gas industries including lower carbon energy.

A list of all parts in the ISO 23936 series can be found on the ISO website.

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.

Introduction

Non-metallic materials are used in the oil and gas industries for a wide range of components. The purpose of this document is to establish requirements and guidelines for systematic and effective planning, for non-metallic material selection to achieve cost effective technical solutions, taking into account possible constraints due to either safety or environmental issues, or both.

This document is of benefit to a broad industry group ranging from operators and suppliers to engineers and authorities. It covers relevant generic types of non-metallic material (e.g. thermosets) and includes the widest range of existing technical experience.

This information aids in material selection. It can be applied to help avoid costly degradation failures of the equipment itself, which could pose a risk to the health and safety of the public and personnel or the environment. This document complements the documents for metallic materials in sour service (the ISO 15156 series). It differs in the form of guidance provided to the user related to the potential degradation of desired properties when used in equipment for oil and gas production environments. The ISO 15156 series provides application limits and qualification requirements for metallic materials in H₂S-containing environments, which are related solely to relevant environmentally assisted cracking mechanisms.

This document recognizes that a wider range of compounds and parameters influence the degradation of non‑metallic materials and thus provides guidance to permit selection of materials for hydrocarbon exploration and production applications based upon stability in appropriate test conditions.

1 Scope

This document provides general principles, requirements and recommendations for the assessment of the stability of thermoset materials that include short fibre filled or particle filled resins and exclude continuous fibre reinforced composites for service in equipment used in oil and gas exploration and production environments. These procedures can be adapted for application within low-carbon energy environments. This document also provides guidance for quality assurance.

This document addresses the resistance of thermosets to the deterioration in properties that can be caused by physical or chemical interaction with produced and injected oil and gas-field media, and with chemical treatment. Interaction with sunlight and ionizing radiation are excluded from the scope of this document.

This document is not necessarily applicable to equipment used in refining or downstream processes and equipment.

The equipment considered includes, but is not limited to, non-metallic pipelines, piping, liners, seals, gaskets and washers. Applications for short-term exposure include pump-down plugs, bridge plug components, line wiper plugs, balls, setting tools and fracking tools. Applications for long-term exposure include bearings and washers. This document excludes tubular products, tanks and similar items produced from continuous fibre reinforced materials.

Blistering by rapid gas decompression is not included in the scope of this document.

This document applies to the assessment of the stability of thermoset materials in simulated hydrocarbon production conditions to aid the selection of materials for equipment designed and constructed using conventional design criteria. Designs utilizing other criteria are excluded from the scope of this document.

2 Normative references

3 Terms, definitions and abbreviated terms

3.1 Terms and definitions

3.2 Abbreviated terms

4 Technical requirements

4.1 General requirements

4.2 Cautionary remarks

4.3 Traceability

4.4 Test specimen identification

4.5 Validation of conformity

5 Level 1 — Material property characterization

5.1 General

5.2 Reporting

6 Level 2 — Material stability (short-term)

6.1 General

6.2 Test criteria

6.3 Preconditioning considerations

6.4 Reporting

7 Level 3 — Material stability (accelerated)

7.1 General

7.2 Exposure temperatures

7.3 Exposure durations

7.4 Exposure fluids

7.5 Initial swelling

7.6 Property test methods

7.7 Threshold criteria

7.8 Preconditioning considerations

7.9 Reporting

8 Level 4 — Material stability (long-term)

8.1 General requirements for Level 4 evaluation

8.2 Exposure temperatures

8.3 Exposure durations

8.4 Exposure fluids

8.5 Initial swelling

8.6 Property test methods

8.7 Preconditioning considerations

8.8 Threshold baseline

8.9 Threshold criteria

9 Additional test considerations

9.1 Fluid ageing

9.2 Functional tests

Bibliography