What is ISO 4925 about?
ISO 4925 is an international standard on road vehicles that discusses methods for quality improvement of hydraulic brake systems. ISO 4925 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 such fluids and equipped with seals, cups or double-lipped type gland seals made of styrene-butadiene rubber (SBR) and ethylene-propylene elastomer (EPDM).
The major use of these fluids is in the hydraulic brake and clutch systems of road vehicles, but they can also be used in any suitable hydraulic system.
Who is ISO 4925 for?
ISO 4925 on hydraulic brake systems is relevant to:
- Automobile industry
- Manufacturer of Brake fluid
Why should you use ISO 4925 ?
A hydraulic brakes system is a braking mechanism that uses brake fluid in oder to transmit force into the system. Non-petroleum-based fluids are used in road-vehicle hydraulic brake and clutch systems. The problem with petroleum-based fluids is that mineral oils and rubber don't mix well.
ISO 4925 provides information on test methods for non-petroleum-based fluids such as viscosity, equilibrium reflux boiling point, fluid stability, corrosion, fluidity and appearance at low temperatures, water tolerance, effect on rubber
As a user of ISO 4925, you can be ensured of the good quality of brake fluid. ISO 4925 helps the user in improving the quality of brake fluid which can improve the braking action and increase the service life of the brake. ISO 4925 enables you to expand the market reach for the product and build consumer trust and confidence.
What’s changed since the last update?
BS ISO 4925:2020 supersedes BS ISO 4925:2005, which is withdrawn.
The main changes compared to the previous edition are as follows:
- Terms and definitions clause was added (Clause 3)
- An additional class 7 is introduced and added to the already existing classes 3, 4, 5-1 and 6
- The reserve alkalinity is added upon request out of the automotive industry
- The intended introduction of a stroking test into a future revision of ISO 4925 is replaced by the intended introduction of a wear and noise test currently under development in the SAE and ISO TF lubrication