ISO 4925-2020 PDF

Full title and description

ISO 4925:2020 — Road vehicles — Specification of non-petroleum-based brake fluids for hydraulic systems. This International Standard specifies requirements, specifications and test methods for non-petroleum-based fluids intended for use in road-vehicle hydraulic brake and clutch systems (suitable for use with seals made of SBR and EPDM).

Abstract

This document provides the specifications, requirements and test methods for non-petroleum-based fluids used in road-vehicle hydraulic brake and clutch systems that are designed for use with seals, cups or double-lipped gland seals made of styrene‑butadiene rubber (SBR) and ethylene‑propylene elastomer (EPDM).

General information

• Status: Published (International Standard; under periodic review).
• Publication date: July 2020.
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 75.120; 43.040.40 (road vehicles; fluids and hydraulic systems).
• Edition / version: Edition 3 (ISO 4925:2020).
• Number of pages: 25 pages.

Scope

ISO 4925:2020 applies to non-petroleum-based (typically glycol‑based) brake and clutch hydraulic fluids intended for road vehicles. The standard defines required properties, test procedures and compatibility guidelines for these fluids when used in systems fitted with SBR or EPDM elastomeric seals. It is focused on ensuring safe and interoperable hydraulic braking/clutch performance across road-vehicle applications.

Key topics and requirements

• Definition and classification of non-petroleum-based brake fluids (scope and intended application).
• Technical requirements and performance criteria to be met by fluids.
• Specified test methods for verifying physical and chemical properties and performance.
• Compatibility requirements with common elastomer materials used in hydraulic systems (SBR and EPDM).
• Conformity and marking expectations to support correct identification and safe use in vehicle systems.

Typical use and users

Primary users include automotive manufacturers, brake-fluid producers and formulators, component and seal manufacturers, independent testing laboratories, conformity assessment bodies and regulatory or technical departments responsible for braking-system safety and compatibility. The standard is used to specify product acceptance criteria, to design compatible hydraulic systems and to support quality-control testing.

Related standards

ISO 4925:2020 replaces ISO 4925:2005 and forms part of the family of vehicle and fluid‑related standards developed by ISO/TC 22/SC 33. A revision cycle and successor draft (ISO/DIS or ISO/FDIS 4925) has been developed and was in the approval pipeline following the 2020 publication. Users should watch for the newer DIS/FDIS release that updates or replaces the 2020 edition.

Keywords

brake fluid; non-petroleum-based; hydraulic brake fluid; road vehicles; brake system fluids; SBR; EPDM; test methods; specifications.

FAQ

Q: What is this standard?

A: ISO 4925:2020 is an international standard that specifies requirements, specifications and test methods for non-petroleum-based brake and clutch fluids intended for road-vehicle hydraulic systems.

Q: What does it cover?

A: It covers the properties, performance criteria and test methods for non-petroleum-based hydraulic fluids and addresses compatibility with common elastomeric seals (styrene‑butadiene rubber and ethylene‑propylene elastomer).

Q: Who typically uses it?

A: Automotive OEMs, brake-fluid manufacturers, component and seal suppliers, test laboratories and conformity assessors use ISO 4925 to define product requirements, conduct testing and ensure compatibility and safety of brake/clutch hydraulic fluids.

Q: Is it current or superseded?

A: ISO 4925:2020 is the published (3rd) edition from July 2020 and is current; ISO has indicated a revision process and a DIS/FDIS for a successor has been developed and was in the approval stages after 2020, so users should check for any published replacement (ISO/DIS or ISO/FDIS 4925).

Q: Is it part of a series?

A: It is part of the ISO/TC 22 series of standards for road vehicles and specifically falls under standards addressing vehicle fluids and braking-system requirements. It directly replaces the 2005 edition (ISO 4925:2005).

Q: What are the key keywords?

A: Key keywords include brake fluid, hydraulic fluid, non-petroleum-based, road vehicles, SBR, EPDM, test methods, specifications and performance criteria.