The SI derived unit (not "derivative") for pressure is pascal (Pa). Hecto and kilo are both valid prefixes. There is nothing I know of in SI that states a preference for kilopascals over hectopascals.
Various disciplines do have their preferences, though. Although kilopascal is preferred for things like tire pressure, meteorologists seem to be split between kilopascals and hectopascals -- with the latter having the convenience of having the same value as the more traditional millibar. Bill Potts, CMS Roseville, CA http://metric1.org [SI Navigator] >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On >Behalf Of G. Stanley Doore >Sent: Friday, December 13, 2002 14:09 >To: U.S. Metric Association >Subject: [USMA:23958] RE: Reply from the Washington Post > > >It's all well and good to try to get the media to use the SI. > >Until the US Government decides that SI and its preferred >derivatives should >be used in the public arena, you will not make much progress. The NOAA >National Weather Service won't even adhere to the SI derivative for >pressure. For example, the NWS uses hPa rather than kPa for pressure >Canada uses kPa to be consistent with other industries in reporting >atmospheric pressure.. > >Regards, Stan Doore > >----- Original Message ----- >From: Stephen C. Gallagher <[EMAIL PROTECTED]> >To: U.S. Metric Association <[EMAIL PROTECTED]> >Sent: Friday, December 13, 2002 9:10 AM >Subject: [USMA:23951] RE: Reply from the Washington Post > > >> >> ----- Original Message ----- >> From: "Terry Simpson" <[EMAIL PROTECTED]> >> To: "U.S. Metric Association" <[EMAIL PROTECTED]> >> Sent: 13 December 2002 08:00 >> Subject: [USMA:23949] RE: Reply from the Washington Post >> >> >> > Stephen C. Gallagher wrote: >> > > I sent a letter to the Washington Post, simply thanking them >> > > for choosing to display Celsius temperature on their website. >> > > >> > > Here is the reply I received today: >> > >> > I also wrote congratulating them and received the identical reply. >> > >> >> Good. It's important to give them positive feedback. They've probably >> gotten a few negative replies from the anti-metric crowd, so whatever >> positive feedback they receive will help balance the scales. >> >> >
