# ISO 2581:1975 — Withdrawn and superseded ISO standards

For ISO 2581:1975, item title is Rigid cellular plastics — Determination of apparent thermal conductivity by means of a heat-flow meter; status code is 9599; successor is ISO 8301:1991; withdrawn / published date is 1975-11-01, recorded from its source on 2026-08-05.

- **Identifier:** ISO 2581:1975 _(verified: appears in the quote below)_
- **Item title:** Rigid cellular plastics — Determination of apparent thermal conductivity by means of a heat-flow meter _(verified: appears in the quote below)_
- **Status code:** 9599 _(verified: appears in the quote below)_
- **Successor:** ISO 8301:1991
- **Withdrawn / published date:** 1975-11-01 _(verified: appears in the quote below)_

## What the source says

> 7554,IS,,ISO 2581:1975,Rigid cellular plastics — Determination of apparent thermal conductivity by means of a heat-flow meter,Plastiques alvéolaires rigides — Détermination de la conductivité thermique apparente au moyen d'un fluxmètre thermique,1975-11-01,1,['83.100'],ISO/TC 61/SC 10,9599,,[15421],"['en','fr']",7,

## 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Part of [Withdrawn and superseded ISO standards](https://referencesource.org/iso-standard-supersessions/).