Conversion Tables and Conversion Formulas

This chapter presents conversion tables and conversion formulas for various measurements units used worldwide. President George H.W. Bush had signed on July 25, 1991, Executive Order 12770, referred to as the Metric Conversion Law, directing U.S. businesses and professionals to use the SI (metric) system as the “preferred” system for weights and measures. The designation SI is derived from Systems International d’unites, the current international designation for the standard metric system of weights and measures. Although engineering, design, and construction professionals in the United States have not fully adopted conversion to the metric system, the increased globalization of these professions requires familiarization with metric conversion units. Imperial units such as inches, feet, yards, and miles are similar to customary U.S. units, but there are some exceptions. The Imperial system uses the term stone instead of pounds—stone is the equivalent of 14 U.S. pounds. The Imperial system also uses long hundredweight, which is equal to 112 U.S. pounds, and it also uses the long ton, equivalent to 2240 U.S. pounds. This chapter guides readers on how to convert inches to feet, feet to meters, hectares to acres, and pounds to kilograms.