ISO 815-2-2019 PDF

Full title and description

ISO 815-2:2019 — Rubber, vulcanized or thermoplastic — Determination of compression set — Part 2: At low temperatures. This International Standard specifies methods for measuring the compression set (permanent deformation after prolonged compression) of vulcanized and thermoplastic rubbers when tested at low temperatures, including two defined test methods and associated apparatus, specimen preparation and measurement procedures.

Abstract

ISO 815-2:2019 defines two methods for determining compression set at low temperatures: Method 1 (based on the traditional assembly and post-recovery thickness measurement) and Method 2 (using a specified device that measures and records thickness during recovery under a defined load). The standard emphasizes that low-temperature effects such as glass hardening or crystallization are reversible on warming and therefore measurements are taken at the test temperature. Due to differences in recovery loading, results from Method 1 and Method 2 are not directly comparable.

General information

• Status: Published, confirmed (current).
• Publication date: November 2019 (Edition 3, 2019).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 83.060 — Elastomers; rubbers.
• Edition / version: Edition 3 (2019).
• Number of pages: 20 pages (ISO edition).

Scope

Specifies procedures for the determination of compression set of vulcanized and thermoplastic rubbers at low temperatures. It gives two alternative methods: Method 1 (compression between polished plates with recovery and measurement at test temperature) and Method 2 (apparatus that allows measurement and recording of thickness during recovery while under load). The standard covers specimen preparation, conditioning, test temperatures and times, measurement accuracy, apparatus requirements for low-temperature environments, and reporting requirements for reproducible results in cold-service assessments.

Key topics and requirements

• Two specified test methods (Method 1 and Method 2) for low-temperature compression set measurement.
• Test-strain guidance by hardness (e.g., typical compressions: 25 % for hardness < 80 IRHD; 15 % for 80–89 IRHD; 10 % for 90–95 IRHD).
• Apparatus requirements: flat, highly polished compression plates, spacer and clamping assemblies, low-temperature cabinet or chamber, and thickness gauges with specified accuracy and measurement pressure.
• Requirement that thickness/recovery measurements be taken at the low test temperature (because low-temperature effects reverse on warming).
• Calibration, specimen handling and conditioning references (cross-references to related ISO documents for conditioning and equipment calibration).
• Reporting requirements that make clear the method used, test temperature, strain applied, specimen details and any apparatus specifics so results can be interpreted or compared.

Typical use and users

Used by rubber test laboratories, material suppliers, compounders, OEMs (automotive, aerospace, cryogenics, oil & gas), quality control/assurance teams and R&D groups to assess low-temperature elastic recovery of seals, gaskets, O‑rings and other components intended for cold-service environments. It supports material selection, specification writing and product qualification for cold-climate or cryogenic applications.

Related standards

Commonly used together with ISO 815-1 (general compression set methods), ISO 23529 (preparing and conditioning of test pieces), ISO 18899 (calibration of test equipment) and other sector-specific test standards that reference compression set behavior.

Keywords

compression set; low temperature; elastomer testing; rubber; vulcanized rubber; thermoplastic rubber; recovery; IRHD; test method; cold service; cryogenic; seals; gaskets.

FAQ

Q: What is this standard?

A: ISO 815-2:2019 is the third edition of the ISO standard that specifies methods for determining the compression set of vulcanized or thermoplastic rubbers when tested at low temperatures.

Q: What does it cover?

A: It covers two test methods for low-temperature compression set, apparatus and specimen requirements, measurement procedures (measurements taken at the test temperature), conditioning and reporting, and guidance on test strain based on material hardness. Results from the two methods are not directly comparable because Method 2 measures recovery under load.

Q: Who typically uses it?

A: Rubber and polymer test laboratories, QC/QA teams, compound formulators and material suppliers, OEMs in automotive, aerospace and cryogenics, and procurement/specification authors who require validated low-temperature performance data.

Q: Is it current or superseded?

A: ISO 815-2:2019 (Edition 3) is published and was reviewed/confirmed in the ISO five‑year review cycle (confirmed in 2024), so this edition is current. Users should check national adoptions or amendments for any local implementations.

Q: Is it part of a series?

A: Yes — it is Part 2 of ISO 815. Part 1 covers general compression set methods; Part 2 specifically addresses low-temperature testing. Other related ISO documents cover specimen conditioning and equipment calibration.

Q: What are the key keywords?

A: Compression set, low temperature, elastomers, rubber testing, recovery, IRHD, seals, gaskets, cryogenic performance.