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International Practical Temperature Scale of 1948: Text Revision of 1960
Summary
The International Practical Temperature Scale of 1948 revises the 1948 scale, enhancing reproducibility. Key changes include adopting the triple point of water and recommending the zinc point for precise temperature measurements.
Area of Science:
- Metrology
- Thermodynamics
- Physical Chemistry
Background:
- The International Temperature Scale of 1948 established standards for temperature measurement.
- Previous scales required revisions to improve accuracy and reproducibility.
- The International Committee on Weights and Measures oversees updates to temperature scales.
Purpose of the Study:
- To present a revised text of the International Temperature Scale of 1948, named the International Practical Temperature Scale of 1948.
- To enhance the reproducibility of temperature measurements.
- To incorporate updated scientific information and recommendations.
Main Methods:
- The scale is based on six fixed, reproducible equilibrium temperatures.
- Interpolation formulas relate temperatures to instrument indications.
- Textual revisions were made to improve the scale's practicality.
Main Results:
- The triple point of water (0.01 °C) replaces the ice point as a defining fixed point.
- The zinc point (419.505 °C) is recommended over the sulfur point.
- Numerical temperature values remain consistent with the 1948 scale.
Conclusions:
- The International Practical Temperature Scale of 1948 offers improved reproducibility.
- Adoption of new fixed points enhances the scale's precision.
- The revised scale reflects advancements in thermometry since 1948.
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