Where Can I Find Authoritative Sources for International Volume Units?

[DaveC426913]

I'm editing a school textbook and have suddenly discovered at the 11th hour that there is a difference between the U.S. cup (236ml), the Canadian cup (227ml) and the British cup (284ml) as well as conflicting results (such as Wiki) that define them differently again - U.S.=250ml, Canadian=240ml. Apparently, the cup is derived from the more basic unit of fluid ounces, and that's not standard either.

I need to find an online soruce that can authoritatively define these differences for the various units of cups, ounces, quarts and gallons.

And I need to have it by - like - tomorrow morning.

Help!

 

[Monique]

Why use cups, use liters.. I don't understand those countries. Who uses elbows or thumbs to measure lenghts? Ofcourse, there are people who still measure in feet

 

[robphy]

Is NIST authoritative enough?
http://physics.nist.gov/Pubs/SP811/appenB8.html
http://ts.nist.gov/WeightsAndMeasures/Publications/upload/appxc.pdf

 

[turbo]

Have you tried Googling on "volumetric measure" "solid measure" "liquid measure" etc? It's probably the only way you're going to get the info you need unless someone has a table of standards at hand.

Edit: robphy had a reference at-hand - posts crossed.

 

[Anttech]

Why use cups, use liters.. I don't understand those countries. Who uses elbows or thumbs to measure lenghts? Ofcourse, there are people who still measure in feet

Dont forget, chains, hands, and furlongs

 

[robphy]

Why liters? Use Planck volumes. http://en.wikipedia.org/wiki/Planck_units

 

[turbo]

Dont forget, chains, hands, and furlongs

I had a Physics professor who threatened (sometimes only half-heartedly) to make us express velocity in furlongs per fortnight. This was in about 1970 and we were presented problems in both metric and US units. Engineering students in the US could not be expected to go out into industry and find much in the way of metric weights and measures, except in the lab. When I worked as a process chemist in a pulp mill (late 70's), all our research and testing was done with metric tools and standards, and then converted to tons, gallons, etc for reporting to the management. That was a pain in the butt, but it had to be done. Pulp mill chemicals were bought by the ton and pulp was sold by the ton and fuel and liquid supplies were purchased by the gallon (mostly Kgallon) and the waste treatment plant (one of my responsibilities) reported in gallons, tons, etc.

 

[Astronuc]

http://ts.nist.gov/WeightsAndMeasures/Metric/upload/Houshold_WM.pdf (US) kitchen units in metric.

Generally - http://ts.nist.gov/WeightsAndMeasures/Metric/mpo_home.cfm


http://www.iso.org/iso/en/prods-services/popstds/quantitiesandunits.html

I am not sure where the 'official' standard would be for comparing the unit of cup to US, Canadian and British units (oz), but NIST and ISO would probably be the one's to do the comparison.

The other possibility would be ANSI - www.ansi.org

One could contact someone like, JoAnn M. Emmel, Ph.D., Virginia Tech and American Association of Family and Consumer Sciences, or the AAFCS - http://www.aafcs.org/

Otherwise, one is left with online calcuators.

Possibly Canadian General Standards Board has a standard for weights and measures. http://www.pwgsc.gc.ca/cgsb/home/index-e.html

And the British - http://www.bsi-global.com/British_Standards/index.xalter

And the Bureau International des Poids et Mesures / International Bureau of Weights and Measures - http://www.bipm.fr/

http://www.sizes.com/units/cup.htm - I don't know how official this is -
http://www.sizes.com/units/index.htm

But then there is this -

cup (c) [1]
a traditional unit of volume used in recipes in the United States. One cup equals 1/2 (liquid) pint, or 8 fluid ounces. Technically, one cup equals exactly 14.4375 cubic inches or approximately 236.6 milliliters, not that anyone measures quite so precisely in the kitchen. American cooks use the same size cup for measuring both liquid and dry substances. In Canada, a cup is equal to 8 Imperial fluid ounces (13.8710 cubic inches or 227.3 milliliters). In Britain, cooks sometimes used a similar but larger unit called the breakfast cup, equal to 10 Imperial fluid ounces.
cup (c) [2]
an informal metric unit of volume equal to 250 milliliters, commonly used in recipes in Australia.
cup (c) [3]
an informal unit of volume for coffee. The size of a cup of coffee varies according to local custom, but a typical size is about 5 fluid ounces or 150 milliliters.

http://www.unc.edu/~rowlett/units/dictC.html

Good luck in resolving this.

 

[sylviaplath]

just use feet and lbs. All of the great writers have used the english system. Harold Bloom, for example, measured everything in cups and gallons.

 

[Integral]

Sheesh! Metric ain't all that!

Just count the prime divisors of 10.

Now count the prime divisorS of 12.

Clearly our foot/inch system is superior in that respect.

Now, consider that you cannot represent .1 precisely in a digital computer. For me this is the death knell of metric. Our archaic and much maligned foot/inch system with fractions of an inch in powers of 2 wins again.

DOWN WITH THE METRIC SYSTEM!

you will have to pry my foot/inch tape measure from my dead hands.

 

[robphy]

Would the Flintstones have adopted base-8 standards?

 

[turbo]

Would the Flintstones have adopted base-8 standards?

Isn't that the cartoon standard?

 

[edward]

This link is from a site called Martindales calculators.

http://www.onlineconversion.com/cooking_volume.htm

 

[DaveC426913]

OK.

1] It's not up to me what I use. That's decided by powers-that-be.

2] "Is NIST authoritative enough?" Well, since all it lists only US units, no.

3] "I am not sure where the 'official' standard would be for comparing the unit of cup to US, Canadian and British units (oz)" Apparently, fluid ounces is the base unit from which the others are derived.


The end result is: we agreed to drop the international units and stick with U.S. only for the sake of brevity.

 

[Astronuc]

I believe each nation has its own Bureau of Weights and Measures, which are historical institutions within the government. NIST is seemingly authoritative, since they do set many scientific and technical standards.


I did find this -
http://www.cs.umbc.edu/~squire/reference/units.shtml

cubic meter = cup x 0.236589E-3 cup = cubic meter x 42267

I believe ISO or the Bureau International des Poids et Mesures / International Bureau of Weights and Measures - http://www.bipm.fr/ are the actual authorities.

Meter, fundamental unit of length, defined as the distance between two
specified lines on a specific bar of platinum-iridium at 0°C at standard
atmospheric pressure supported at two neutral points 0.285 meter from the
center of the bar. The bar is kept at the International Bureau of Weights
and Measures near Paris France.

http://www.cs.umbc.edu/~squire/reference/units.shtml

So it would appear that BIPM/IBWM is the official keeper of the standards regarding dimensions.

In the US - "NIST is an agency of the U.S. Commerce Department's Technology Administration," and it "promotes uniformity in US weights and measures laws, regulations, and standards to achieve equity between buyers and sellers in the marketplace." from NIST - http://ts.nist.gov/WeightsAndMeasures/owm_about.cfm