The dalton is in Table 7. Footnote "c" says: The dalton (Da) and the unified atomic mass unit (u) are alternate names for the same unit . . ." (It is one of the units which must be determined experimentally, but is accepted for use with the SI) The four radiation units are the curie, roentgen, rad and rem, accepted for use in the US, but not by the CIPM for use with the SI. Their continues is strongly discouraged, however. The gauss is one of those CGS units in Table 9, more softly deprecated than previously, in both the SI Brochure and NIST SP330.
--- On Sun, 4/19/09, Jeremiah MacGregor <jeremiahmacgre...@rocketmail.com> wrote: From: Jeremiah MacGregor <jeremiahmacgre...@rocketmail.com> Subject: [USMA:44766] Re: IEEE/ASTM SI-10 To: "U.S. Metric Association" <usma@colostate.edu> Date: Sunday, April 19, 2009, 1:33 PM Since the dalton is precisely defined as one twelfth of the mass of an isolated atom of carbon-12 (12C) at rest and in its ground state[1], then does the dalton become an SI base unit, a supplementary unit or a non-SI unit accepted along with SI? Obviously it can not be a derived unit. The katal is a derived unit as it is equal to 1 mol/s, being derived from two base units, the mole and the second. Are you referring to the rem and rad? Do you know what the status of the gauss is in the US? Jerry From: John M. Steele <jmsteele9...@sbcglobal.net> To: U.S. Metric Association <usma@colostate.edu> Sent: Saturday, April 18, 2009 10:48:43 AM Subject: [USMA:44737] Re: IEEE/ASTM SI-10 I'm not on the committee. As a minimum, some changes that need to be reflected: *The katal is approved as a new derived unit. *The dalton is accepted as equivalent to the unified atomic mass unit *The SI Brochure has taken a softer stance on certain non-SI units. *NIST has continued the acceptance of certain metric, but not SI, ionizing radiation units for the US. The prior edition of SP330 had set a deadline of 2000. (I'm not sure I agree with it, but Congress charges them to write the rules for the US). *There were some editorial style changes that perhaps need to be reflected. Those changes in driving documents need to be reflected. Since I don't have a copy and am not on the committee, I have no idea what else. --- On Sat, 4/18/09, Jeremiah MacGregor <jeremiahmacgre...@rocketmail.com> wrote: From: Jeremiah MacGregor <jeremiahmacgre...@rocketmail.com> Subject: [USMA:44736] Re: IEEE/ASTM SI-10 To: "U.S. Metric Association" <usma@colostate.edu> Date: Saturday, April 18, 2009, 9:49 AM I'm curious as to what is needed to be revised or updated. Unless there is a new unit or prefix added to the list of units or the definition of a unit changes then there should be no need to revise or update the SI standard. So what revisions are being made? Jerry From: John M. Steele <jmsteele9...@sbcglobal.net> To: U.S. Metric Association <usma@colostate.edu> Sent: Saturday, April 18, 2009 7:57:00 AM Subject: [USMA:44732] Re: IEEE/ASTM SI-10 I don't own a current copy and don't see a need for one. The SI Brochure, and NIST SP330 and SP811 suffice for my purposes and heavily overlap the content. However, I had a copy in the early 70's. I was helping the electronics company I worked for then go metric, in addition to my regular engineering duties. As I recall, it had some information helpful to organizations transitioning from Customary or dual to metric, particularly on rounding. (Rounding nominal or target values is pretty straightforward; rounding minimum and maximums from specs requires either rounding "specward" or some engineering judgementor both.) I don't feel it is needed in organizations that ARE metric, but that is a personal opinion and others may feel differently. Also, it is (at least partially) out of date whenever a new edition of the SI Brochure comes out. It takes time for the NIST and ANSI publications to catch up. (although revisions from 7th to 8th SI Brochure are not earthshaking) --- On Fri, 4/17/09, Jeremiah MacGregor <jeremiahmacgre...@rocketmail.com> wrote: From: Jeremiah MacGregor <jeremiahmacgre...@rocketmail.com> Subject: [USMA:44717] Re: IEEE/ASTM SI-10 To: "U.S. Metric Association" <usma@colostate.edu> Date: Friday, April 17, 2009, 10:04 PM Why pay for a publication from the ANSI when the same information is available for free from the BIPM. http://www.bipm.org/en/si/ Jerry
