# ISO 3968:1981 — Withdrawn and superseded ISO standards

For ISO 3968:1981, item title is Hydraulic fluid power — Filters — Evaluation of pressure drop versus flow characteristics; status code is 9599; successor is ISO 3968:2001; withdrawn / published date is 1981-12-01, recorded from its source on 2026-08-05.

- **Identifier:** ISO 3968:1981 _(verified: appears in the quote below)_
- **Item title:** Hydraulic fluid power — Filters — Evaluation of pressure drop versus flow characteristics _(verified: appears in the quote below)_
- **Status code:** 9599 _(verified: appears in the quote below)_
- **Successor:** ISO 3968:2001
- **Withdrawn / published date:** 1981-12-01 _(verified: appears in the quote below)_

## What the source says

> 9629,IS,,ISO 3968:1981,Hydraulic fluid power — Filters — Evaluation of pressure drop versus flow characteristics,Transmissions hydrauliques — Filtres — Évaluation de la perte de charge en fonction du débit,1981-12-01,1,['23.100.60'],ISO/TC 131/SC 6,9599,,[28057],"['en','fr']",7,"<p>Specifies the method of measuring the pressure drop across a fluid filter under various conditions of flow. Two standards of measurement are specified: class A - for accurate evaluation for referee purposes - requiring laboratory conditions; class B - for evaluation for general purposes - requiring test facilities less stringent that laboratory conditions. Figure 1 shows an example for a suitable test circuit, and

## Source

- https://isopublicstorageprod.blob.core.windows.net/opendata/_latest/iso_deliverables_metadata/csv/iso_deliverables_metadata.csv

Last verified: 2026-08-05. Review by: 2027-02-01.
Part of [Withdrawn and superseded ISO standards](https://referencesource.org/iso-standard-supersessions/).