ISO 1 is an international standard set by the International Organization for Standardization that specifies the standard reference temperature for geometrical product specification and verification. The temperature is fixed at 20 degrees Celsius (°C), which exactly equals both 293.15 kelvin (K) and 68 degrees Fahrenheit (°F).

ISO 1:2016 defines the concepts of a reference temperature and of the standard reference temperature, and specifies the standard reference temperature value for the specification of geometrical and dimensional properties of an object.

INTERNATIONAL STANDARD ISO 1:2022(E) Geometrical product specifications (GPS) — Standard reference temperature for the specification of geometrical and dimensional properties 1 Scope This document defines the concepts of a reference temperature and the standard reference temperature

ISO 1:2016(E) Introduction This International Standard is a geometrical product specification (GPS) standard and is to be regarded as a fundamental GPS Standard (see ISO 14638:2015 [1]). For more detailed information on the relationship of this International Standard to other standards and the GPS matrix model, see Annex B.

In this paper, we discuss the motivation for these changes and present several issues debated during the revision process for the benefit of future standards committees that might study this topic. Key words: CTE; dimensional metrology; ISO 1; standard reference temperature, thermal expansion. 1. Introduction.

ISO 3166-1 alpha-2 – two-letter country codes which are also used to create the ISO 3166-2 country subdivision codes and the Internet country code top-level domains. ISO 3166-1 alpha-3 – three-letter country codes which may allow a better visual association between the codes and the country names than the 3166-1 alpha-2 codes.

The 2016 revision of ISO 1 now specifies the meaning of the reference temperature and the standard reference temperature used to specify geometric and dimensional properties of an object and maintains the long established value of the standard reference temperature at 20 °C.

Sep 1, 2016 · This International Standard defines the concepts of a reference temperature and of the standard reference temperature, and specifies the standard reference temperature value for the specification of geometrical and dimensional properties of an object.