General Notices and Requirements Applying to Standards, Tests, Assays, and Other Specifications of the United States Pharmacopeia The General Notices and Requirements (hereinafter referred to as the General Notices) and general requirements appearing in General Chapters provide in summary from the basic guidelines for the interpretation and application of the standards, tests, assays, and other specifications of the Units States Pharmacopeia and eliminate the need to repeat throughout the book those requirements that are pertinent in numerous instances. Where no specific language is given to the contrary, the requirements under the General Notices and General Chapters apply. Where exceptions to the General Notices or General Chapters are made, the wording in the individual monograph takes precedence and specifically indicates the directions or the intent. To emphasize that such exceptions do exist, the General Notices or General Chapters in some places employ where indicators a qualifying expression such as “unless otherwise specified.” In the individual monographs, it is understood that the specific wording of standards, tests, assays, and other specifications is binding wherever deviations from the General Notices or General Chapters exist whether or not a statement of exception is made. WEIGHTS AND MEASURES The International System of Units (SI) is used in this Pharmacopeia. The SI metric and other unit and the symbols commonly employed, are as follows. Bq = becquerel
| L =
| liter
| kBq = kilobecquerel
| mL =
| milliliter
| MBq = megabecquerel
| μL =
| microliter
| GBq = gigabecquerel
| Eq =
| gram-equivalent weight
| Ci = curie
| mEq =
| milliequivalent
| mCi = millicurie
| mol =
| gram-molecular weight (mole)
| μCi = microcurie
| Da =
| dalton (relative molecular mass)
| nCi = nanocurie
| mmol =
| millimole
| Gy = gray
| Osmol =
| osmole
| mGy = milligray
| mOsmol =
| milliosmole
| m = meter
| Hz =
| hertz
| dm = decimeter
| kHz =
| kilohertz
| cm = centimeter
| MHz =
| megahertz
| mm = millimeter
| V =
| volts
| μm = micrometer (0.001mm)
| MeV =
| million electron volts
| nm = nanometer
| keV =
| kilo-electron volt
| kg = kilogram
| mV =
| millivolt
| g = gram
| psi =
| pounds per square inch
| mg = milligram
| Pa =
| pascal
| μg; mcg = microgram
| kPa =
| kilopascal
| ng = nanogram
| g =
| gravity (in centrifugation)
| pg = picrogram
|
|
| fg = femtogram
|
|
| dL = deciliter
|
|
| * Formerly the symbol mμ (for millimicron) was used.
| ** The gram is the unit of mass that is used to measure quantities of materials. Weight, which is a measure of the gravitational force acting on the mass of a material, is proportional to, and may differ slightly from, its mass because of the effects of factors such as gravity, temperature, latitude, and altitude, and altitude. The difference between mass and weight is considered to be insignificant for compendial assays an tests, and the term “weight” is used throughout USP and NF.
| * Formerly the abbreviation mcg was used in the Pharmacopeial monographs; however, the symbol μg now is more widely accepted and thus is used in this Pharmacopeia. The term “gamma,” symbolized by γ , is frequently used for microgram in biochemical literature.
| Note—The abbreviation mcg is still commonly employed to denote microgram(s) in labeling and in prescription writing. Therefore, for purposes of labeling, “mcg” may be used to denote microgram(s).
| *One milliliter (mL) is used herein as the equivalent of 1 cubic centimeter (cc).
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