BS EN ISO 25457-2023 PDF

Full title and description

STB BS EN ISO 25457-2023 — Oil and gas industries including lower carbon energy — Flare details for general refinery and petrochemical service. This standard gives requirements and guidance for the selection, design, specification, operation and maintenance of flares and associated combustion and mechanical components used in pressure‑relieving and vapour‑depressurizing systems for petroleum, petrochemical and natural gas facilities (onshore focus with offshore guidance).

Abstract

Specifies requirements and provides guidance and best practices for the selection, mechanical details, design, operation and maintenance of flare systems and related equipment for refinery and petrochemical service. The document is primarily intended for onshore facilities but includes relevant offshore guidance and is published as a supplement to API 537 (3rd edition) where applicable.

General information

• Status: Published (International Standard; adopted as BS EN ISO 25457:2023 by BSI).
• Publication date: ISO edition published October 2023 (Edition 2, 2023); BS adoption/publication entries around 30 October–6 November 2023 for the BSI release.
• Publisher: International Organization for Standardization (ISO); British Standards Institution (BSI) for the BS EN ISO adoption.
• ICS / categories: 75.180.20 — Processing equipment (flare and related equipment).
• Edition / version: Edition 2 (2023). Replaces ISO 25457:2008.
• Number of pages: ISO edition metadata shows a short published file (listed as 2 pages by the ISO bibliographic entry); the BS EN ISO (BSI) publication listings report a BS product of around 10 pages for the adopted EN/BS text and separate tracked‑change/redline publications that are much longer (e.g. 146 pages for the TC/redline document). Users should check the exact national publication (ISO vs BS/EN vs redline TC) for the copy they purchase.

Scope

Provides requirements and guidance for selection, design, specification, operation and maintenance of flares and associated combustion and mechanical components used in pressure‑relieving and vapour‑depressurizing systems for petroleum, petrochemical and natural gas industries. The scope covers general refinery and petrochemical service, is primarily aimed at onshore facilities, and includes guidance relevant to offshore installations. It supplements relevant industry guidance (notably API 537) and replaces the earlier 2008 edition.

Key topics and requirements

• Selection and specification of flare headers, tips, pilots and mechanical components.
• Design details for combustion systems, pilot arrangements and ignition systems.
• Guidance on operation, routine checks and maintenance of flare systems.
• Mechanical details and data‑sheet formats to communicate design information.
• Alignment with API 537 (3rd edition) where applicable, with exceptions noted in the standard.

Typical use and users

Used by process, mechanical and safety engineers, plant designers, flare system manufacturers, operations and maintenance teams, procurement/specification teams, inspection bodies and regulators involved in petroleum, petrochemical and natural gas facilities. Also used as a reference in design reviews, commissioning and audits of flare systems.

Related standards

Directly related to and used alongside API 537 (flare tip/combustion guidance) and other ISO/EN standards on processing equipment and pressure‑relief systems. This edition replaces ISO 25457:2008 and is published as EN/BS adoption material in markets that adopt EN ISO texts. National adoptions (UNE, ÖNORM, BSI) follow the ISO text with local publication metadata.

Keywords

flare, flare tip, flare system, combustion, pilot, pressure relief, vapour depressurizing, refinery, petrochemical, natural gas, API 537, processing equipment, maintenance, design.

FAQ

Q: What is this standard?

A: An ISO international standard (adopted as BS EN ISO 25457:2023) that provides requirements and guidance for flare details used in general refinery and petrochemical service (selection, design, operation and maintenance).

Q: What does it cover?

A: Selection and mechanical details for flares, combustion system details (tips, pilots, ignition), operation and maintenance practices, and data‑sheet/communication formats for flare design; intended primarily for onshore facilities with some offshore guidance.

Q: Who typically uses it?

A: Process and mechanical engineers, flare system designers and manufacturers, operations and maintenance teams, inspection and regulatory bodies in the oil, gas and petrochemical sectors.

Q: Is it current or superseded?

A: Current — Edition 2 (2023) is the published replacement for ISO 25457:2008. National/EN/BS adoptions were published in late 2023 (and associated tracked‑change/redline outputs issued by BSI in November 2023). Verify the specific national adoption/version you hold for pagination and any national forewords.

Q: Is it part of a series?

A: It sits within ISO/TC 67 work on processing equipment (ICS 75.180.20) and is related to other ISO, EN and API documents covering pressure‑relief systems and associated equipment; it is not a numbered multi‑part ISO series but can be used alongside other standards in the processing equipment family.

Q: What are the key keywords?

A: Flare, flare tip, pilot, combustion, pressure relieving, vapour depressurizing, refinery, petrochemical, natural gas, maintenance, design.