BS EN ISO 1-2016 pdf download.Geometrical product specifications (GPS) – Standard reference temperature for the specification of geometrical and dimensional properties (ISO 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. Some examples of geometrical and dimensional properties include size, location, orientation (including angle), form and surface texture of a workpiece.
This International Standard is also applicable to the definition of the measurand used in verification or calibration.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1 reference temperature
temperature of an object, having a uniform temperature, specified as part of the definition of a geometrical or dimensional property
Note ito entry: The specification of a geometrical or dimensional property is typically given in technical product documentation, e.g., on an engineering drawing or in a CAD file, or in the specification of the measurand (the quantity intended to be measured).
2.2 standard reference temperature
internationally agreed-upon reference temperature
Note ito entry: In prior editions of this International Standard, the term “standard reference temperature was defined as its assigned numerical value, i.e. 20 °C. In this edition, the definition of the reference temperature (2.1) and the assignment of a standardized value to this temperature are separately addressed (Clause 3).
3 Standard reference temperature value for the specification of geometrical and dimensional properties
The standard reference temperature value for the specification of geometrical and dimensional properties shall be fixed at 20 °C. Unless otherwise explicitly specified, the reference temperature for geometrical and dimensional properties of workpieces shall be the standard reference temperature. See Annex A for information on the use of the reference temperature specification.
NOTE 1 There is only one standard reference temperature value and it is fixed at 20 °C. However, this does not prevent a different (non-standard) reference temperature from being specified for all geometrical and dimensional properties of a workpiece or for a specific geometrical or dimensional property on a workpiece, provided it is explicitly stated as part of the specification.
NOTE 2 The specification of a non-standard reference temperature may increase the measurement uncerainty during verification because most dimensional measuring equipment and gauges are calibrated with their measurand defined at the standard reference temperature.BS EN ISO 1 pdf download.