Pat, National Institute of Standards and Technology (NIST) is an arm of the U.S. Government, under the U.S. Secretary of Commerce. Under our law the Secretary of Commerce "interprets" SI, and he or she also appoints our representatives to the CGPM organizations.
NIST Special Publication 330 is almost identical to the English language edition of the BIPM SI Brochure, but SP 330 uses American spellings and has a few notes. For example, it defends curie, roentgen, rad, and rem because those units still appear in U.S. law. NIST SP 811, "Guide for the Use of the International System of Units (SI)," is authored by Barry N. Taylor, our representative on the CCU. It carries the considerable weight of his authority and is of course an approved U.S. Government publication. It is not, however, a "standard." American National Standard IEEE/ASTM SI 10-1997 is the product of the U.S. consensus standardization process, which involves industry, government, and public users. The standard is prepared and approved by IEEE and ASTM and then submitted to the American National Standards Institute for its approval process, to verify consensus. In general, the documents agree, and U.S. users are free to use any or all (and, unfortunately, to use feet, pounds, etc., as well). Where do they differ? In general the American National Standard is a little more restrictive concerning non-SI units. Thus it deprecates the use of the angstrom and the bar, although they are still "currently accepted for use with the International System" according to the BIPM SI Brochure. Our national standard consensus is that, when and as we finally adopt the metric system, we ought to go for good clean SI practice. Bruce Barrow, Secretary Joint IEEE/ASTM Committee ----- Original Message ----- From: "Pat Naughtin" <[EMAIL PROTECTED]> To: "U.S. Metric Association" <[EMAIL PROTECTED]> Sent: Monday, June 10, 2002 6:04 PM Subject: [USMA:20384] Primary American National Standard > Dear Bruce, > > In a recent posting to the USMA listserver (Re: [USMA:20377] Re: Billion > definition) you stated: > > Standard IEEE/ASTM SI 10-1997, (is) the primary American National Standard > on metric practice, > > Could you elaborate on this a little further for me please? How do NIST > Special documents 330 and 811 fit into the hierarchy that you imply? > > I am not disagreeing with you, I simply don't know how the system works in > the USA. > > Thanks for your help. > > Pat Naughtin CAMS > Geelong, Australia > >
