I'm reposting this because it does not seem to have made it onto the USMA list the first time:
Hello Everyone, Today I received a reply to my challenge to the Associated Press (see below). At the bottom of this message is a copy of my original letter, which I sent to Louis Boccardi (President of the Associated Press) and to Norm Goldstein (the editor of the Associated Press Stylebook and Libel Manual). Today's response was from Mr. Boccardi. Norm Goldstein just received his letter on 13 November (from the delivery confirmation) and has not yet responded. I would be interested in your thoughts on Mr. Boccardi's response. Here it is: November 7, 2001 Louis D. Boccardi President and Chief Executive Officer The Associated Press 50 Rockefeller Plaza New York, NY 10020-1666 Mr. J. Jason Wentworth Historian Poker Flat Research Range 213 2nd Ave. Fairbanks, AK 99701-4810 Dear Mr. Wentworth: Thank you for your interesting letter of Oct. 31st about metric usage. I will ask our stylebook group to review the relevant entries and our practices. Perhaps some changes are in order, but "American layman" that you may be, you seem far ahead of the metric familiarity possessed by most Americans. It may be that "Americans have had more than enough exposure to metric symbols to know what the common ones stand for" but I'll walk down a lot of American Main Streets before I find large numbers of people who would know what the string you listed means. And if we write stories readers can't understand we have served no one. All the same, you raise the sort of questions we should review and we will. Thank you for bringing them to our attention. Finally, I fly a lot and have never heard a domestic captain give the temperature only in Celsius. We clearly fly different airlines. Sincerely, Louis Boccardi +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+= 2001 October 31 J. Jason Wentworth, Historian Poker Flat Research Range http://www.pfrr.alaska.edu 213 2nd Ave. Fairbanks, AK 99701-4810 Mr. Norm Goldstein and Mr. Louis D. Boccardi President and Chief Executive Officer The Associated Press 50 Rockefeller Plaza New York, NY 10020 Dear Mr. Goldstein, I am writing to you regarding an issue that has become more important now that the United States is militarily involved in Afganistan. I wanted to bring to your attention an Associated Press practice that degrades the clarity of the reports (especially international reports and science reports) and contradicts the principles set forth in The Associated Press Stylebook and Libel Manual. In international and science stories from Associated Press reporters, the original metric units supplied in the source material are almost invariably converted (often incorrectly) to the colloquial US units. Also, the original metric units are seldom included in parentheses after the colloquial unit conversions, even though this is called for in The Associated Press Stylebook and Libel Manual. The Associated Press Stylebook's instructions for handling metric units are as follows: **************************************************************************** ***** --METRIC SYSTEM-- In general, metric terms should be included in a story when they are relevant. There are no hard-and-fast rules on when they are relevant, but the following two guidelines have been developed to cover questions likely to arise as metric measurements gain increased acceptance in the United States: -- Use metric terms when they are the primary form [emphasis mine - J.J.W.] in which the source of a story has provided statistics. Follow the metric units with equivalents in the terms more widely known in the United States. Normally, the equivalent should be in parentheses after the metric figure. A general statement such as: "A kilometer equals about five-eighths of a mile," would be acceptable, however, to avoid repeated use of parenthetical equivalents in a story that uses kilometers many times. -- Provide metric equivalents for traditional forms if a metric unit has become widely known. As speedometers with kilometer markings become more prevalent, for example, a story about speed limits might list miles per hour and provide kilometers per hour in parentheses [emphasis mine - J.J.W.]. **************************************************************************** ***** I am an American layman, and I understand the metric system as well as the hodge-podge of colloquial US units. I drink 500 milliliter, 1 liter, and 2 liter soft drinks and bottled water, I have run in "2 K" and "5 K" (2 kilometer and 5 kilometer) races, and I use 35 mm film and 2 kilogram packages of detergent tablets. (One liter of water weighs one kilogram, so I know how heavy a kilogram feels.) The AP Stylebook also says that no metric abbreviations (they are actually universal, language-independent symbols) other than 'mm' for 'millimeter' should be used. Americans have had more than enough exposure to metric symbols to know what the common ones (g, kg, t, mm, cm, m, km, m/s, km/h, mL, L, �C, etc.) stand for. When I read Associated Press international reports and science reports that contain colloquial US units instead of the original metric units, I feel like I'm being "talked-down to," as if we Americans are too ignorant to understand metric units. I think the problem is, sadly, that many American reporters are functionally innumerate and so assume that their readers are also innumerate. There is no reason for the Associated Press to continue to "dumb down" units of measurement for American consumption. The last Olympic Games that were held in Australia were reported almost entirely in metric units, and no Americans seem to have complained that they didn't understand the units. Also, when I fly domestically it is a fairly common event for the captain to announce the destination airport temperature in degrees Celsius only. I have never heard any of my fellow passengers ask each other, "What is that in Fahrenheit?" As the historian for the Poker Flat Research Range, I write press releases and occasional articles about range activities. I use metric units exclusively, as I have found that the public actually does understand them. When using unfamiliar metric units such as the hectare (ha), I describe them using visual comparisons that don't require conversions to corresponding colloquial units. For example, a hectare (1 square hectometer; the prefix hecto denotes 100) is the area of a square with 100 m X 100 m sides (10,000 square meters). Since a football field with its end zones is approximately 100 m long, I describe a hectare as being a square with sides approximately the length of a football field with its end zones. Also, 1 kilometer is easy to visualize as being approximately the length of 10 football fields (with their end zones) laid end-to-end. >From my experience, I have found that it is not necessary to include colloquial equivalents for the common, everyday metric units that people see on food and medicine labels or on television (micrograms, milligrams, grams, kilograms, tonnes, nanometers, micrometers, millimeters, centimeters, meters, kilometers, meters per second, kilometers per hour, milliliters, liters, cubic meters, degrees Celsius, etc.). The less familiar units (hectares, newtons, hectopascals, etc.) are easy to describe because they are all based on the meter and the kilogram. I never give a colloquial unit conversion because it is a mental "crutch" for the readers. Using a visual comparison gives the readers a real "feel" for the metric unit. I have written a metric style and usage guide that I use as a reference, and I have enclosed a copy of it for you. The current national emergency has illuminated the fact that in a democracy, a free press has a responsibility to educate as well as inform the citizens. This conflict is global, and other countries, friend and foe alike, use metric units. Now that our military (which is also metricated) is involved in Afganistan, it is time for the Associated Press to take the lead in using the world's units of measurement to describe the world's war. I would be most grateful to you for your help. Sincerely Yours, J. Jason Wentworth, Historian (Tel/Fax: 907-457-6682) Poker Flat Research Range http://www.pfrr.alaska.edu Geophysical Institute University of Alaska Fairbanks Enclosure =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+ METRIC STYLE & USAGE GUIDE by J. Jason Wentworth, Historian University of Alaska Poker Flat Research Range Note: The author makes no copyright claims on this work. Reproduction and distribution of this work are permitted provided that acknowledgement is given to the author. The author is the historian for the Poker Flat Research Range http://www.pfrr.alaska.edu/ , a sounding rocket launch facility located 48 km north of Fairbanks, Alaska. This guide was written with rocketry and spaceflight subjects in mind, but it is equally applicable to other fields. [1] Use centimeters (cm) or millimeters (mm) for dimensions smaller than 1 meter (1 m). Millimeters are generally used for dimensions smaller than 500 mm (50 cm or 0.5 m) although it's not a hard-and-fast rule. For example, the Black Brant sounding rocket is 438 mm in diameter. Its diameter has also been listed as 43.8 cm. [2] Meters (m) expressed to two decimal places are used for dimensions equal to or larger than 1 m (there's no need to write 1.00 m if it's exactly 1 m, of course). If the reader desires, s/he can easily convert this to centimeters by simply mentally moving the decimal point (for example, India's PSLV satellite launch vehicle is 1.34 m [134 cm] in diameter). When describing very large objects or distances (tall buildings, bridges, river widths, field lengths, etc.), the whole number values (for example, 753 m) are sufficient. [3] Grams (g) are used for masses of less than 1 kilogram (1 kg or 1000 g). [4] Kilograms (kg) are used to express masses equal to or greater than 1000 g (1 kg). It is usually expressed to one decimal place (for example, 17.9 kg). Masses equal to or greater than 1000 kg are given in tonnes (metric tons; the symbol is "t"). 1 tonne (1 t) = 1000 kilograms. [5] Volume is expressed in milliliters (ml or mL) for volumes of less than 1 liter (1 l or 1 L), which is 1000 milliliters. This applies to "empty volume" (capacity) as well as the volume of liquid or gas in a container. 1 mL equals 1 cubic centimeter, so cubic centimeters (written out that way) or cm3 (with a superscript 3) can also be used. The old unofficial symbol "cc" should never be used to express cubic centimeters. For larger volumes, use cubic meters (m3 with a superscript 3). [6] Velocity is expressed in kilometers per hour (km/h, NOT kph) or kilometers per second (km/s) for large velocities. For small velocities (such as between two spacecraft about to dock), meters per second (m/s) and centimeters per second (cm/s) are used (the latter for velocities of less than 1 m/s). [7] Area is expressed in hectares (ha -- 1 ha equals 1 square hectometer, which is 10,000 square meters) or square kilometers (km2, with a superscript 2). When square in shape, a 1 ha field has sides that are 100 m long. Smaller areas are expressed in square meters (m2), square centimeters (cm2) or square millimeters (mm2). The "less than one" guide applies here as well. If an area is smaller than 1 km2, use hectares. If it's smaller than 1 ha, use m2 and so on. [8] Altitudes and distances are expressed in meters (m) or kilometers (km) [the latter if it's equal to or greater than 1000 m]. [9] Temperatures are expressed in degrees Celsius (written out that way or with the degree symbol and a capital "C" [�C]). Do not use "Centigrade." [10] Pressure (including barometric pressure) is expressed in kilopascals (kPa) or hectopascals (hPa). Do not use millibars, torrs or millimeters of mercury. Meteorologists and weather services in many countries prefer to express barometric pressure in hPa because 1 millibar = 1 hPa. [11] Force is measured in newtons (N). Rocket thrust is also expressed in newtons (N), and kilonewtons (kN) are used for very powerful rockets. A rocket's total impulse is given in newton-seconds (written out that way or with N�s). Do not use N-sec or N-s. [12] The specific impulse of a rocket propellant is expressed by the symbol N�s/kg or... (kg.(m/s2).s)/kg which reduces to m/s, the "exhaust velocity." N�s/kg is preferable because it shows the readers (lay people as well as the technically inclined) the connection between specific impulse, total impulse (newton-seconds or N�s) and thrust (newtons or N). The style guidelines for the proper use of metric symbols are very simple. The symbols (mm, kg, hPa, etc.) are NOT abbreviations, as they are used universally regardless of language or alphabet. The unit names, however, are spelled and pronounced differently in other languages (for example, "kilometer" is spelled "quilometro" in Spanish). The guidelines for their proper use can be found on this "sub-page" of the U.S. Metric Association (USMA) web site: http://lamar.colostate.edu/~hillger/correct.htm Here is a link to the main USMA site: http://lamar.colostate.edu/~hillger/ The definitions of all of the metric units are listed on the main USMA site. A detailed explanation of specific impulse (kindly provided by U.S. Metric Association member Gene Mechtly) is included below. ******************************************************************** The "differential (an increment) of Impulse" (dI) is "Thrust" (a Force, F) exerted over an "increment of time" (denoted by the differential dt), i.e. dI = F.dt. Total Impulse is thrust (F) integrated over time; i.e. the integral of F(t).dt where the thrust varies with time, denoted abstractly as F(t) "Specific Impulse" is Impulse per increment of mass expelled. In differential form, F.dt/dm. The SI units are N.s/kg, or ... (kg.(m/s2).s)/kg which reduces to m/s, the "exhaust velocity." Recall the *error* of equating lbf to lbm in the equation F.t/m (in finite form) to get, incorrectly, specific impulse in seconds, an error which appears frequently in the older literature on rocket propulsion. Note that the ion propulsion engine, recently discussed in NASA news releases, has much higher exhaust velocities than chemical rocket engines (i.e. much larger total impulse from the available mass to be expelled) and is therefore better suited for propulsion of probes into "deep space." **************************************************************** J. Jason Wentworth, Historian Tel/Fax: (907) 457-6682 Poker Flat Research Range http://www.pfrr.alaska.edu/ Geophysical Institute University of Alaska Fairbanks
