GOST 20869-75 PDF

Full title and description

GOST 20869-75 — "Пластмассы ячеистые жесткие. Метод определения водопоглощения" / "Rigid cellular plastics. Method for determination of water absorption". A Soviet-era test standard that defines how to determine water absorption properties of rigid cellular (foam) plastic materials.

Abstract

This standard specifies a laboratory method for determining the water absorption behaviour of rigid cellular plastics. It covers sample selection and preparation, the immersion and measurement procedure used to quantify water uptake (expressed as change in mass and/or volume) and the form of reporting test results. GOST 20869-75 was the original 1975 edition and has since been superseded by a modernized version (GOST 20869-2017) harmonized with international practice.

General information

• Status: Superseded / replaced (replaced by GOST 20869-2017).
• Publication date: Approved 27 May 1975; introduced/entered into force 1 July 1976.
• Publisher: State Committee for Standards of the USSR (Gosstandart) — issued as an interstate standard.
• ICS / categories: 83.100 (Rubber and plastics industries; plastics — rigid cellular plastics).
• Edition / version: Original 1975 edition (designation suffix "-75").
• Number of pages: 4.

Scope

Applies to rigid cellular plastics (rigid foam plastics) and establishes a standardized laboratory procedure for determining their water absorption characteristics. The method is intended to provide comparable, repeatable measurements for quality control, material specification and comparative testing across manufacturers and testing laboratories.

Key topics and requirements

• Definition of the material class covered (rigid cellular/foam plastics) and applicable sample forms.
• Requirements for sample preparation and conditioning prior to testing.
• Specified immersion and measurement procedure to quantify water uptake (methodology for weighing/measurement before and after exposure).
• Calculation and expression of water absorption results (typically as percent change in mass and/or volume or equivalent metric).
• Reporting format for test results and essential test conditions to be recorded (temperature, duration, sample geometry, etc.).
• References to related test methods and normative documents used for apparatus, distilled water, environmental conditions and measurement equipment.

Typical use and users

Used by materials and product manufacturers (producers of rigid foam plastics such as rigid polyurethane foam, polystyrene-based foams and similar materials), independent testing laboratories, quality and conformity assessment bodies, product development teams and procurement/specification authors who require standardized water absorption data for selection, acceptance or design purposes.

Related standards

The 1975 standard was later replaced by GOST 20869-2017 (which aligns with ISO 2896 in its scope). Normative and related references commonly cited with this test method include international and national test standards for distilled water, sample dimensions and environmental conditions and material-specific measurement standards (examples of related GOST/ISO documents referenced historically include ISO 2896 and GOST documents such as GOST 5632‑72, GOST 6709‑72, GOST 10354‑73 and GOST 12423‑66).

Keywords

GOST 20869-75; rigid cellular plastics; foam plastics; water absorption; test method; Gosstandart; USSR standard; plastics testing; ISO 2896.

FAQ

Q: What is this standard?

A: GOST 20869-75 is a Soviet-era standard titled "Rigid cellular plastics. Method for determination of water absorption" that defines a laboratory test procedure to measure how much water rigid foam plastics absorb.

Q: What does it cover?

A: It covers sample preparation, conditioning, immersion/measurement procedures and calculation/reporting of water absorption for rigid cellular plastics so that results are repeatable and comparable between laboratories and manufacturers.

Q: Who typically uses it?

A: Material manufacturers, product developers, testing and certification laboratories, quality-control departments and specification writers who need standardized water absorption data for rigid foam plastic products.

Q: Is it current or superseded?

A: It is superseded. GOST 20869-75 has been replaced by a modernized standard, GOST 20869-2017 (the newer standard is aligned with international practice and entered into force in 2018).

Q: Is it part of a series?

A: It belongs conceptually to the family of standards dealing with testing and specification of plastics and cellular (foam) materials. The 2017 replacement references and aligns with ISO 2896; older and related GOST test-method standards are referenced for apparatus, water quality and environmental conditions.

Q: What are the key keywords?

A: Rigid cellular plastics, foam plastics, water absorption, test method, GOST 20869-75, water uptake, materials testing.