Rules for SAE Use of SI (Metric) Units
This SAE Standard provides information on the International System of Units (abbreviated SI in all languages), and its application in measurement unit usage.
The purpose is to provide information on SI and guidance on SI's correct, uniform usage in application to land, sea, and aerospace design, engineering, and manufacturing practices and technical communications.
This document and the referenced IEEE/ASTM/ANSI SI 10 Standard, establish rules for the use of SI units in SAE technical reports, including Standards, Recommended Practices, and Information Reports, as well as technical papers, publications, etc. This TSB 003 document is designated as applicable for goverance of SI metric practice in all SAE operations, internal and external communications, products, and services.
Throughout this document, SI is intended to include recognized SI units, as established by the General Conference on Weights and Measures (CGPM), and a limited number of other units that, formally, are not SI units.
SI forms the foundation of international metric standardization. But it is recognized, worldwide, that certain exceptions are required. For example: the degree (of plane angle), the minute, and the hour, are non-SI units. The decibel is another example.
This document provides guidance and authoritative references for acceptable use of certain non-SI units within the SAEÕs operations, practices, services, and products.