Introduction - ASTM International

In the text, use unit symbols after numbers denoting a definite quantity. Example: "The tensile strength is 45,000 psi (310 MPa)." Use unit symbols in tables and figures, and in lists defining symbols used in equations. Use unit symbols and abbreviations in the singular only. Thus "fifty kilograms" shall be designated "50 kg," not "50 kgs." ................
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