ISO 3722-1976 PDF

Full title and description

ISO 3722:1976 — Hydraulic fluid power — Fluid sample containers — Qualifying and controlling cleaning methods. Defines a method to qualify and control cleaning procedures for sample containers so that particulate contamination analyses of hydraulic fluids are not degraded by container cleanliness.

Abstract

Specifies a method and provides criteria to ensure that the accuracy of particulate contamination analyses in hydraulic systems is not degraded by insufficient cleanliness of fluid sample containers. The document gives definitions and tabulates inspection ratios together with AQQL/AOQL values of concern.

General information

• Status: Published (international standard; current stage noted as "to be revised").
• Publication date: September 1976 (published 1976-09; effective/public availability 1 Sep 1976 in most catalogs).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 23.100.99 (Other fluid power system components / contamination control context).
• Edition / version: Edition 1 (1976).
• Number of pages: 2.

Scope

ISO 3722:1976 specifies a test/qualification method and establishes means for ensuring that particulate contamination analyses of hydraulic fluids remain accurate by controlling the cleanliness of sample containers. It defines inspection ratios and lists the AQQL/AOQL values used as acceptance criteria for container cleaning methods.

Key topics and requirements

• Qualification procedures for cleaning methods applied to fluid sample containers (to demonstrate that cleaning achieves required cleanliness levels).
• Inspection ratios and sampling plans for checking container cleanliness.
• Specification and use of AQQL / AOQL (average outgoing quality limit) values as limits of concern when evaluating cleaning performance.
• Definitions related to sample containers and contamination-control terminology used in particulate contamination analysis.
• Practical control measures to ensure sampled fluid is representative and not biased by container contamination (handling, storage, inspection).

Typical use and users

Used by hydraulic system manufacturers, maintenance and reliability teams, independent fluid-analysis laboratories, procurement and quality managers selecting or approving sample containers, and standards/quality engineers responsible for contamination-control programs. The standard is applied where particle-count accuracy in hydraulic-fluid sampling is required.

Related standards

Closely related standards include ISO 4406 (hydraulic fluid contamination coding by particle counts) and ISO 11171 (calibration of automatic particle counters for liquids); both are commonly used alongside ISO 3722 when performing particulate contamination analysis and reporting. ISO/WD 3722.3 is a working draft under development intended to replace ISO 3722:1976.

Keywords

hydraulic fluid power; fluid sample containers; cleaning methods; particulate contamination; sample cleanliness; inspection ratios; AQQL / AOQL; contamination control; particle counting.

FAQ

Q: What is this standard?

A: An ISO international standard (ISO 3722:1976) that defines how to qualify and control cleaning methods for fluid sample containers used in hydraulic fluid particulate contamination analysis.

Q: What does it cover?

A: It covers methods to demonstrate and control container cleanliness, inspection/sampling ratios, definitions relevant to sample containers, and AQQL/AOQL acceptance values to ensure container cleanliness does not degrade particle-count results.

Q: Who typically uses it?

A: Laboratories performing fluid particle counting, OEMs and hydraulic-system maintainers, procurement/quality teams approving sampling supplies, and standards/contamination-control specialists.

Q: Is it current or superseded?

A: ISO 3722:1976 remains a published ISO document but is shown in ISO records with a review stage indicating it is to be revised; a working draft ISO/WD 3722.3 is under development to replace it. Users should check ISO publications or national standards bodies for the latest status before relying on it for compliance.

Q: Is it part of a series?

A: It is part of the hydraulic fluid power / contamination-control work program of ISO/TC 131/SC 6 and is commonly used together with related contamination and particle-counting standards (for example ISO 4406 and ISO 11171).

Q: What are the key keywords?

A: Sample container cleaning, particulate contamination, hydraulic fluid, inspection ratios, AQQL/AOQL, contamination control, particle counting.