Handbook 44 - 2008 Appendix D – Definitions 

Appendix D 

Definitions 

The specific code to which the definition applies is shown in [brackets] at the end of the definition. Definitions for the 

General Code [1.10] apply to all codes in Handbook 44. 

A 

absolute value. The absolute value of a number is the magnitude of that number without considering the positive or 

negative sign.[2.20] 

acceptance test. The first official test of a farm milk tank, at a particular location, in which the tank is accepted as 

correct. This test applies to newly constructed tanks, relocated used tanks, and recalibrated tanks.[4.42] 

accurate. A piece of equipment is "accurate" when its performance or value–that is, its indications, its deliveries, its 

recorded representations, or its capacity or actual value, etc., as determined by tests made with suitable 

standards-conforms to the standard within the applicable tolerances and other performance requirements. Equipment that 

fails so to conform is "inaccurate." (Also see "correct.")[1.10] 

all-class. A description of a multi-class calibration that includes all the classes of a grain type. [5.56(a), 5.57] 

(Added 2007) 

analog or digital recorder. An element used with a belt-conveyor scale that continuously records the rate-of-flow of 

bulk material over the scale (formerly referred to as a chart recorder).[2.21] 

(Amended 1989) 

analog type. A system of indication or recording in which values are presented as a series of graduations in combination 

with an indicator, or in which the most sensitive element of an indicating system moves continuously during the operation 

of the device.[1.10] 

animal scale. A scale designed for weighing single heads of livestock.[2.20] 

(Amended 1987) 

apparent mass versus 8.0 g/cm3

. The apparent mass of an object versus 8.0 g/cm3 is the mass of material of density 

8.0 g/cm3

 that produces exactly the same balance reading as the object when the comparison is made in air with a density 

of 1.2 mg/cm3

 at 20 °C.[3.37] 

approval seal. A label, tag, stamped or etched impression, or the like, indicating official approval of a device. (Also see 

"security seal.")[1.10] 

assumed atmospheric pressure. The average atmospheric pressure agreed to exist at the meter at various ranges of 

elevation, irrespective of variations in atmospheric pressure from time to time.[3.33] 

audit trail. An electronic count and/or information record of the changes to the values of the calibration or configuration 

parameters of a device.[1.10, 2.20, 2.21, 2.24, 3.30, 3.37, 5.56(a)] 

(Added 1993) 

automatic bulk weighing system. A weighing system adapted to the automatic weighing of bulk commodities in 

successive drafts of predetermined amounts, automatically recording the no-load and loaded weight values and 

accumulating the net weight of each draft.[2.20] 

automatic checkweigher. An automatic weighing system that does not require the intervention of an operator during the 

weighing process and used to subdivide items of different weights into one or more subgroups, such as identifying 

packages that have acceptable or unacceptable fill levels according to the value of the difference between their weight and 

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Appendix D – Definitions Handbook 44 - 2008 

a pre-determined set point. These systems may be used to fill standard packages for compliance with net weight 

requirements.[2.24] 

(Amended 2004) 

automatic gravimetric filling machine (instrument). A filling machine or instrument that fills containers or packages 

with predetermined and virtually constant mass of product from bulk by automatic weighing, and which comprises 

essentially an automatic feeding device or devices associated with one or more weighing unit and the appropriate 

discharge devices.[2.24] 

(Added 2004) 

automatic hopper scale. One adapted to the automatic weighing of bulk commodity in successive drafts of 

predetermined amounts. (This is not an "automatic-indicating scale" defined below.)[2.20] 

automatic temperature or density compensation. The use of integrated or ancillary equipment to obtain from the 

output of a volumetric meter an equivalent mass, or an equivalent liquid volume at the assigned reference temperature 

below and a pressure of 14.696 lb/in2

 absolute. 

Cryogenic liquids – 21 °C (70 °F)[3.34] 

Hydrocarbon gas vapor – 15 °C (60 °F)[3.33] 

Liquid carbon dioxide – 21 °C (70 °F)[3.38] 

Liquefied petroleum gas (LPG) and Anhydrous ammonia – 15 °C (60 °F)[3.32] 

Petroleum liquid fuels and lubricants – 15 °C (60 °F)[3.30] 

automatic weighing system (AWS). An automatic weighing system is a weighing device that, in combination with other 

hardware and/or software components, automatically weighs discrete items and that does not require the intervention of 

an operator during the weighing process. Examples include, but are not limited to, weigh-labelers and 

checkweighers.[2.24] 

(Amended 2004) 

automatic zero-setting mechanism (belt-conveyor scale). A zero setting device that operates automatically without 

intervention of the operator after the belt has been running empty.[2.21] 

(Added 2002) 

automatic zero-tracking mechanism. See "automatic zero-tracking mechanism" under “zero-setting mechanism.”[2.20, 

2.22, 2.24] 

automatic-indicating scale. One on which the weights of applied loads of various magnitudes are automatically 

indicated throughout all or a portion of the weighing range of the scale. (A scale that automatically weighs out commodity in predetermined drafts, such as an automatic hopper scale, a packaging scale, and the like, is not an 

"automatic-indicating" scale.)[2.20. 2.22] 

auxiliary indicator. Any indicator other than the master weight totalizer that indicates the weight of material determined 

by the scale.[2.21] 

axle-load scale. A scale permanently installed in a fixed location, having a load-receiving element specially adapted to 

determine the combined load of all wheels (1) on a single axle or (2) on a tandem axle of a highway vehicle.[2.20] 

B 

badge. A metal plate affixed to the meter by the manufacturer showing the manufacturer's name, serial number and 

model number of the meter, and its rated capacity.[3.33] 

balance, zero-load. See "zero-load balance."[2.20] 

balance indicator. A combination of elements, one or both of which will oscillate with respect to the other, for 

indicating the balance condition of a nonautomatic indicating scale. The combination may consist of two indicating 

edges, lines, or points, or a single edge, line, or point and a graduated scale.[2.20] 

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Handbook 44 - 2008 Appendix D – Definitions 

balancing mechanism. A mechanism (including a balance ball) that is designed for adjusting a scale to an accurate 

zero-load balance condition.[2.20] 

base pressure. The absolute pressure used in defining the gas measurement unit to be used, and is the gauge pressure at 

the meter plus an agreed atmospheric pressure.[3.33] 

basic time rate. The charge for time for all intervals except the initial interval.[5.54] 

basic tolerances. Basic tolerances are those tolerances on underregistration and on overregistration, or in excess and in 

deficiency, that are established by a particular code for a particular device under all normal tests, whether maintenance or 

acceptance. Basic tolerances include minimum tolerance values when these are specified. Special tolerances, identified 

as such and pertaining to special tests, are not basic tolerances.[1.10] 

basic distance rate. The charge for distance for all intervals except the initial interval.[5.54] 

batching meter. A device used for the purpose of measuring quantities of water to be used in a batching operation.[3.36] 

beam scale. One on which the weights of loads of various magnitudes are indicated solely by means of one or more 

weighbeam bars either alone or in combination with counterpoise weights.[2.20] 

beam. See "weighbeam."[2.20] 

bell prover. A calibrated cylindrical metal tank of the annular type with a scale thereon that, in the downward travel in a 

surrounding tank containing a sealing medium, displaces air through the meter being proved or calibrated.[3.33] 

belt-conveyor. An endless moving belt for transporting material from place to place.[2.21] 

belt-conveyor scale. A device that employs a weighing element in contact with a belt to sense the weight of the material 

being conveyed and the speed (travel) of the material, and integrates these values to produce total delivered weight.[2.21] 

belt-conveyor scale systems area. The scale system area refers to the scale suspension, weigh idlers attached to the scale 

suspension, 5 approach (-) idlers, and 5 retreat (+) idlers.[2.21] 

(Added 2001) 

billed weight. The weight used in the computation of the freight, postal, or storage charge, whether actual weight or 

dimensional weight.[5.58] 

binary submultiples. Fractional parts obtained by successively dividing by the number 2. Thus, one-half, one-fourth, 

one-eighth, one-sixteenth, and so on, are binary submultiples.[1.10] 

built-for-purpose device. Any main device or element which was manufactured with the intent that it be used as, or part 

of, a weighing or measuring device or system.[1.10] 

(Added 2003) 

C 

calibration parameter. Any adjustable parameter that can affect measurement or performance accuracy and, due to its 

nature, needs to be updated on an ongoing basis to maintain device accuracy, e.g., span adjustments, linearization factors, 

and coarse zero adjustments.[2.20, 2.21, 2.24, 3.30, 3.37, 5.56(a)] 

(Added 1993) 

carbon dioxide liquid-measuring device. A system including a mechanism or machine of (a) the meter or (b) a 

weighing type of device mounted on a vehicle designed to measure and deliver liquid carbon dioxide. Means may be 

provided to indicate automatically, for one of a series of unit prices, the total money value of the quantity measured.[3.38] 

car-wash timer. A timer used in conjunction with a coin-operated device to measure the time during which car-wash 

water, cleaning solutions, or waxing solutions are dispensed.[5.55] 

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Appendix D – Definitions Handbook 44 - 2008 

center-reading tank. One so designed that the gauge rod or surface gauge, when properly positioned for use, will be 

approximately in the vertical axis of the tank, centrally positioned with respect to the tank walls.[4.43] 

cereal grain and oil seeds. Agricultural commodities including, but not limited to, corn, wheat, oats, barley, flax, rice, 

sorghum, soybeans, peanuts, dry beans, safflower, sunflower, fescue seed, etc.[5.56(a), 5.56(b)] 

chart recorder. See analog or digital recorder. 

(Amended 1989) 

check rate. A rate of flow usually 20 % of the capacity rate.[3.33] 

checkweighing scale. One used to verify predetermined weight within prescribed limits.[2.24] 

class of grain. Hard Red Winter Wheat as distinguished from Hard Red Spring Wheat as distinguished from Soft Red 

Winter Wheat, etc.[5.56(a), 5.56(b), 5.57] 

clear interval between graduations. The distance between adjacent edges of successive graduations in a series of 

graduations. If the graduations are "staggered," the interval shall be measured, if necessary, between a graduation and an 

extension of the adjacent graduation. (Also see "minimum clear interval.")[1.10] 

cleared. A taximeter is "cleared" when it is inoperative with respect to all fare indication, when no indication of fare or 

extras is shown and when all parts are in those positions in which they are designed to be when the vehicle on which the 

taximeter is installed is not engaged by a passenger.[5.54] 

cold-tire pressure. The pressure in a tire at ambient temperature.[5.53, 5.54] 

computing type or computing type device. A device designed to indicate, in addition to weight or measure, the total 

money value of product weighed or measured, for one of a series of unit prices.[1.10] 

computing scale. One that indicates the money values of amounts of commodity weighed, at predetermined unit prices, 

throughout all or part of the weighing range of the scale.[2.20] 

concave curve. A change in the angle of inclination of a belt conveyor where the center of the curve is above the 

conveyor.[2.21] 

concentrated load capacity (CLC) (also referred to as Dual Tandem Axle Capacity (DTAC). A capacity rating of a 

vehicle or axle-load scale, specified by the manufacturer, defining the maximum load applied by a group of two axles 

with a centerline spaced 4 feet apart and an axle width of 8 feet for which the weighbridge is designed. The concentrated 

load capacity rating is for both test and use.[2.20] 

(Added 1988) (Amended 1991, 1994, and 2003) 

configuration parameter. Any adjustable or selectable parameter for a device feature that can affect the accuracy of a 

transaction or can significantly increase the potential for fraudulent use of the device and, due to its nature, needs to be 

updated only during device installation or upon replacement of a component, e.g., division value (increment), sensor 

range, and units of measurement.[2.20, 2.21, 2.24, 3.30, 3.37, 5.56(a)] 

(Added 1993) 

consecutive-car test train. A train consisting of cars weighed on a reference scale, then coupled consecutively and run 

over the coupled-in-motion railway track scale under test.[2.20] 

(Added 1990) 

construction materials hopper scale. A scale adapted to weighing construction materials such as sand, gravel, cement, 

and hot oil.[2.20] 

contract sale. A sale where a written agreement exists, prior to the point of sale, in which both buyer and seller have 

accepted pricing conditions of the sale. Examples include, but are not limited to: e-commerce, club sales, or preD-4 
Handbook 44 - 2008 Appendix D – Definitions 

purchase agreements. Any devices used in the determination of quantity must comply with NIST Handbook 44.[3.30, 

3.32, 3.37] 

(Added 1993) (Amended 2002) 

conventional scale. If the use of conversion tables is necessary to obtain a moisture content value, the moisture meter 

indicating scale is called "conventional scale." The values indicated by the scale are dimensionless.[5.56(b)] 

conversion table. Any table, graph, slide rule, or other external device used to determine the moisture content from the 

value indicated by the moisture meter.[5.56(b)] 

correction table. Any table, graph, slide rule, or other external device used to determine the moisture content from the 

value indicated by the moisture meter when the indicated value is altered by a parameter not automatically corrected for 

in the moisture meter (for example, temperature or test weight).[5.56(b)] 

convex curve. A change in the angle of inclination of a belt conveyor where the center of the curve is below the 

conveyor.[2.21] 

conveyor stringers. Support members for the conveyor on which the scale and idlers are mounted.[2.21] 

correct. A piece of equipment is "correct" when, in addition to being accurate, it meets all applicable specification 

requirements. Equipment that fails to meet any of the requirements for correct equipment is "incorrect." (Also see 

"accurate.")[1.10] 

counterbalance weight(s). One intended for application near the butt of a weighbeam for zero-load balancing 

purposes.[2.20] 

counterpoise weight(s). A slotted or "hanger" weight intended for application near the tip of the weighbeam of a scale 

having a multiple greater than one.[2.20] 

coupled-in-motion railroad weighing system. A device and related installation characteristics consisting of (1) the 

associated approach trackage, (2) the scale (i.e., the weighing element, the load-receiving element, and the indicating 

element with its software), and (3) the exit trackage which permit the weighing of railroad cars coupled in motion.[2.20, 

2.23] 

(Added 1992) 

crane scale. One with a nominal capacity of 5000 pounds or more designed to weigh loads while they are suspended 

freely from an overhead, track-mounted crane.[2.20] 

cryogenic liquid-measuring device. A system including a liquid-measuring element designed to measure and deliver 

cryogenic liquids in the liquid state.[3.34] 

(Amended 1986 and 2003) 

cryogenic liquids. Fluids whose normal boiling point is below 120 kelvin (-243 °F).[3.34] 

cubic foot, gas. The amount of a cryogenic liquid in the gaseous state at a temperature of 70 °F and under a pressure of 

14.696 lb/in2

 absolute that occupies one cubic foot. (See NTP.)[3.34] 

D 

“d,” dimension division value. The smallest increment that the device displays for any axis and length of object in that axis.[5.58] 

d, value scale division. See "scale division, value of (d)."[2.20, 2.22] 

Dmax (maximum load of the measuring range). Largest value of a quantity (mass) which is applied to a load cell during 

test or use. This value shall not be greater than Emax.[2.20]

(Added 2005) 

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Appendix D – Definitions Handbook 44 - 2008 

Dmin (minimum load of the measuring range). Smallest value of a quantity (mass) which is applied to a load cell 

during test or use. This value shall not be less than Emin.[2.20] 

(Added 2006) 

dairy-product-test scale. A scale used in determining the moisture content of butter and/or cheese or in determining the 

butterfat content of milk, cream, or butter.[2.20] 

decimal submultiples. Parts obtained by successively dividing by the number 10. Thus 0.1, 0.01, 0.001, and so on are 

decimal submultiples.[1.10] 

decreasing-load test. A test for automatic-indicating scales only, wherein the performance of the scale is tested as the 

load is reduced.[2.20, 2.22] 

(Amended 1987) 

deficiency. See "excess and deficiency."[1.10] 

digital type. A system of indication or recording of the selector type or one that advances intermittently in which all 

values are presented digitally, or in numbers. In a digital indicating or recording element, or in digital representation, 

there are no graduations.[1.10] 

dimensional weight (or dim, weight). A value computed by dividing the object’s volume by a conversion factor; it may 

be used for the calculation of charges when the value is greater than the actual weight.[5.58] 

(Added 2004) 

direct sale. A sale in which both parties in the transaction are present when the quantity is being determined. An 

unattended automated or customer-operated weighing or measuring system is considered to represent the device/business 

owner in transactions involving an unattended device.[1.10] 

(Amended 1993) 

discharge hose. A flexible hose connected to the discharge outlet of a measuring device or its discharge line.[3.30, 3.31, 

3.32, 3.34, 3.37, 3.38] 

(Added 1987) 

discharge line. A rigid pipe connected to the outlet of a measuring device.[3.30, 3.31, 3.32, 3.34, 3.37] 

(Added 1987) 

discrimination (of an automatic-indicating scale). The value of the test load on the load-receiving element of the scale 

that will produce a specified minimum change of the indicated or recorded value on the scale.[2.20, 2.22] 

dispenser. See motor-fuel device.[3.30, 3.37] 

distributed-car test train. A train consisting of cars weighed first on a reference scale, cars coupled consecutively in 

groups at different locations within the train, then run over the coupled-in-motion railway track scale under test. The 

groups are typically placed at the front, middle, and rear of the train.[2.20] 

(Added 1990) 

dry-hose type. A type of device in which it is intended that the discharge hose be completely drained following the 

mechanical operations involved in each delivery. (See "dry hose.")[3.30, 3.31, 3.34, 3.35] 

dry hose. A discharge hose intended to be completely drained at the end of each delivery of product. (See "dry-hose 

type.")[3.30, 3.31] 

(Amended 2002) 

dynamic monorail weighing system. A weighing system which employs hardware or software to compensate for 

dynamic effects from the load or the system that do not exist in static weighing, in order to provide a stable indication. 

Dynamic factors may include shock or impact loading, system vibrations, oscillations, etc., and can occur even when the 

load is not moving across the load receiving element.[2.20] 

(Added 1999) 

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Handbook 44 - 2008 Appendix D – Definitions 

E 

e, value of verification scale division. See "verification scale division, value of (e)."[2.20] 

Emax (maximum capacity). Largest value of a quantity (mass) which may be applied to a load cell without exceeding the 

mpe.[2.20] 

(Added 2005) 

emin (minimum verification scale division). The smallest scale division for which a weighing element complies with the 

applicable requirements.[2.20, 2.21, 2.24] 

(Added 1997) 

Emin (minimum dead load). Smallest value of a quantity (mass) which may be applied to a load cell during test or use 

without exceeding the mpe.[2.20] 

(Added 2006) 

electronic link. An electronic connection between the weighing/load receiving or other sensing element and indicating 

element where one recognizes the other and neither can be replaced without calibration.[2.20] 

(Added 2001) 

element. A portion of a weighing or measuring device or system which performs a specific function and can be separated, 

evaluated separately, and is subject to specified full or partial error limits. 

(Added 2002) 

equal-arm scale. A scale having only a single lever with equal arms (that is, with a multiple of one), equipped with two 

similar or dissimilar load-receiving elements (pan, plate, platter, scoop, or the like), one intended to receive material being

weighed and the other intended to receive weights. There may or may not be a weighbeam.[2.20] 

event counter. A nonresettable counter that increments once each time the mode that permits changes to sealable 

parameters is entered and one or more changes are made to sealable calibration or configuration parameters of a 

device.[2.20, 2.21, 3.30, 3.37, 5.54, 5.56(a), 5.56(b), 5.57] 

(Added 1993) 

event logger. A form of audit trail containing a series of records where each record contains the number from the event counter 

corresponding to the change to a sealable parameter, the identification of the parameter that was changed, the time and date 

when the parameter was changed, and the new value of the parameter.[2.20, 2.21, 3.30, 3.37, 5.54, 5.56(a), 5.56(b), 5.57] 

(Added 1993) 

excess and deficiency. When an instrument or device is of such a character that it has a value of its own that can be 

determined, its error is said to be "in excess" or "in deficiency," depending upon whether its actual value is, respectively, 

greater or less than its nominal value. (See "nominal.") Examples of instruments having errors "in excess" are: a linear 

measure that is too long; a liquid measure that is too large; and a weight that is "heavy." Examples of instruments having 

errors "in deficiency" are: a lubricating-oil bottle that is too small; a vehicle tank compartment that is too small; and a 

weight that is "light."[1.10] 

extras. Charges to be paid by a passenger in addition to the fare, including any charge at a flat rate for the transportation 

of passengers in excess of a stated number and any charge for the transportation of baggage.[5.54] 

F 

face. That side of a taximeter on which passenger charges are indicated.[5.54] 

face. That portion of a computing-type pump or dispenser which displays the actual computation of price per unit, 

delivered quantity, and total sale price. In the case of some electronic displays, this may not be an integral part of the 

pump or dispenser.[3.30] 

(Added 1987) 

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Appendix D – Definitions Handbook 44 - 2008 

fare. That portion of the charge for the hire of a vehicle that is automatically calculated by a taximeter through the 

operation of the distance and/or time mechanism.[5.54] 

farm milk tank. A unit for measuring milk or other fluid dairy product, comprising a combination of (1) a stationary or 

portable tank, whether or not equipped with means for cooling its contents, (2) means for reading the level of liquid in the 

tank, such as a removable gauge rod or a surface gauge, and (3) a chart for converting level-of-liquid readings to volume; 

or such a unit in which readings are made on gauge rod or surface gauge directly in terms of volume. Each compartment 

of a subdivided tank shall, for purposes of this code, be construed to be a "farm milk tank."[4.43] 

feeding mechanism. The means for depositing material to be weighed on the belt conveyor.[2.21] 

fifth wheel. A commercially-available distance-measuring device which, after calibration, is recommended for use as a 

field transfer standard for testing the accuracy of taximeters and odometers on rented vehicles.[5.53, 5.54] 

fifth-wheel test. A distance test similar to a road test, except that the distance traveled by the vehicle under test is 

determined by a mechanism known as a "fifth-wheel" that is attached to the vehicle and that independently measures and 

indicates the distance.[5.53, 5.54] 

flag. A plate at the end of the lever arm or similar part by which the operating condition of a taximeter is controlled and 

indicated.[5.54] 

fractional bar. A weighbeam bar of relatively small capacity for obtaining indications intermediate between notches or 

graduations on a main or tare bar.[2.20] 

ft3

/h. Cubic feet per hour.[3.33] 

G 

gasoline gallon equivalent (GGE). Gasoline gallon equivalent (GGE) means 5.660 pounds of natural gas.[3.37] 

(Added 1994) 

gasoline liter equivalent (GLE). Gasoline liter equivalent (GLE) means 0.678 kilograms of natural gas.[3.37] 

(Added 1994) 

gauge pressure. The difference between the pressure at the meter and the atmospheric pressure (psi).[3.33] 

gauge rod. A graduated, "dip-stick" type of measuring rod designed to be partially immersed in the liquid and to be read 

at the point where the liquid surface crosses the rod.[4.42] 

gauging. The process of determining and assigning volumetric values to specific graduations on the gauge or gauge rod 

that serve as the basis for the tank volume chart.[4.42] 

graduated interval. The distance from the center of one graduation to the center of the next graduation in a series of 

graduations. (Also see "value of minimum graduated interval.")[1.10] 

graduation. A defining line, or one of the lines defining the subdivisions of a graduated series. The term includes such 

special forms as raised or indented or scored reference "lines" and special characters such as dots. (Also see "main 

graduation" and "subordinate graduation.")[1.10] 

grain class. Different grains within the same grain type. For example, there are six classes for the grain type “wheat:” 

Durum Wheat, Hard Red Spring Wheat, Hard Red Winter Wheat, Soft Red Winter Wheat, Hard White Wheat, and Soft 

White Wheat.[5.56(a), 5.57] 

(Added 2007) 

grain hopper scale. One adapted to the weighing of individual loads of varying amounts of grain.[2.20] 

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Handbook 44 - 2008 Appendix D – Definitions 

grain moisture meter. Any device indicating either directly or through conversion tables and/or correction tables the 

moisture content of cereal grains and oil seeds. Also termed "moisture meter."[5.56(a), 5.56(b)] 

grain sample. That portion of grain or seed taken from a bulk of grain or seed to be bought or sold and used to determine 

the moisture content of the bulk.[5.56(a), 5.56(b)] 

grain-test scale. A scale adapted to weighing grain samples used in determining moisture content, dockage, weight per 

unit volume, etc.[2.20] 

grain type. See “kind of grain.”[5.56(a), 5.57] 

(Added 2007) 

gravity discharge. A type of device designed for discharge by gravity.[3.30, 3.31] 

H 

head pulley. The pulley at the discharge end of the belt conveyor. The power drive to drive the belt is generally applied 

to the head pulley.[2.21] 

hired. A taximeter is "hired" when it is operative with respect to all applicable indications of fare or extras. The 

indications of fare include time and distance where applicable unless qualified by another indication of "Time Not 

Recording" or an equivalent expression.[5.54] 

hopper scale. A scale designed for weighing bulk commodities whose load-receiving element is a tank, box, or hopper 

mounted on a weighing element. (Also, see "automatic hopper scale," "grain hopper scale," and "construction materials 

hopper scale."[2.20] 

I 

idler space. The center-to-center distance between idler rollers measured parallel to the belt.[2.21] 

idlers or idler rollers. Freely turning cylinders mounted on a frame to support the conveyor belt. For a flat belt, the 

idlers consist of one or more horizontal cylinders transverse to the direction of belt travel. For a troughed belt, the idlers

consist of one or more horizontal cylinders and one or more cylinders at an angle to the horizontal to lift the sides of the 

belt to form a trough.[2.21] 

in-service light indicator. A light used to indicate that a timing device is in operation.[5.55] 

increasing-load test. The normal basic performance test for a scale in which observations are made as increments of test 

load are successively added to the load-receiving element of the scale.[2.20, 2.22] 

increment. The value of the smallest change in value that can be indicated or recorded by a digital device in normal 

operation.[1.10] 

index of an indicator. The particular portion of an indicator that is directly utilized in making a reading.[1.10] 

indicating element. An element incorporated in a weighing or measuring device by means of which its performance 

relative to quantity or money value is "read" from the device itself as, for example, an index-and-graduated-scale 

combination, a weighbeam-and-poise combination, a digital indicator, and the like. (Also see "primary indicating or 

recording element.")[1.10] 

indicator, balance. See "balance indicator."[2.20] 

initial zero-setting mechanism. Automatic means provided to set the indication to zero at the time the instrument is 

switched on and before it is ready for use.[2.20] 

(Added 1990) 

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Appendix D – Definitions Handbook 44 - 2008 

initial distance or time interval. The interval corresponding to the initial money drop.[5.54] 

interval, graduated. See "graduated interval."[1.10] 

interval, clear, between graduations. See "clear interval between graduations."[1.10] 

J 

jewelers' scale. One adapted to weighing gems and precious metals.[2.20] 

K 

kind of grain. Corn as distinguished from soybeans as distinguished from wheat, etc.[5.56(a), 5.56(b)] 

L 

label. A printed ticket, to be attached to a package, produced by a printer that is a part of a prepackaging scale or that is 

an auxiliary device.[2.20] 

large-delivery device. Devices used primarily for single deliveries greater than 200 gallons, 2000 pounds, 20 000 cubic 

feet, 2000 liters, or 2000 kilograms.[3.34, 3.38] 

laundry-drier timer. A timer used in conjunction with a coin-operated device to measure the period of time that a 

laundry drier is in operation.[5.55] 

liquefied petroleum gas vapor-measuring device. A system including a mechanism or device of the meter type, 

equipped with a totalizing index, designed to measure and deliver liquefied petroleum gas in the vapor state by definite 

volumes, and generally installed in a permanent location. The meters are similar in construction and operation to the 

conventional natural- and manufactured-gas meters.[3.33] 

liquefied petroleum gas. A petroleum product composed predominantly of any of the following hydrocarbons or 

mixtures thereof: propane, propylene, butanes (normal butane or isobutane), and butylenes.[3.31, 3.32, 3.33, 3.34, 3.37] 

liquefied petroleum gas liquid-measuring device. A system including a mechanism or machine of the meter type 

designed to measure and deliver liquefied petroleum gas in the liquid state by a definite quantity, whether installed in a 

permanent location or mounted on a vehicle. Means may or may not be provided to indicate automatically, for one of a 

series of unit prices, the total money value of the liquid measured.[3.33] 

(Amended 1987) 

liquid volume correction factor. A correction factor used to adjust the liquid volume of a cryogenic product at the time 

of measurement to the liquid volume at NBP.[3.34] 

liquid-fuel device. A device designed for the measurement and delivery of liquid fuels.[3.30] 

liquid-measuring device. A mechanism or machine designed to measure and deliver liquid by definite volume. Means 

may or may not be provided to indicate automatically, for one of a series of unit prices, the total money value of the liquid 

measured, or to make deliveries corresponding to specific money values at a definite unit price.[3.30] 

liquid fuel. Any liquid used for fuel purposes, that is, as a fuel, including motor-fuel.[3.30, 3.31] 

livestock scale. A scale equipped with stock racks and gates and adapted to weighing livestock standing on the scale 

platform.[2.20] 

(Amended 1989) 

load-receiving element. That element of a scale that is designed to receive the load to be weighed; for example, 

platform, deck, rail, hopper, platter, plate, scoop.[2.20, 2.21, 2.23] 

load cell. A device, whether electric, hydraulic, or pneumatic, that produces a signal (change in output) proportional to 

the load applied.[2.20, 2.21, 2.23] 

D-10 
Handbook 44 - 2008 Appendix D – Definitions 

load cell verification interval (v). The load cell interval, expressed in units of mass, used in the test of the load cell for 

accuracy classification.[2.20, 2.21] 

(Added 1996) 

loading point. The location at which material to be conveyed is applied to the conveyor.[2.21] 

low-flame test. A test simulating extremely low-flow rates such as caused by pilot lights.[3.33] 

lubricant device. A device designed for the measurement and delivery of liquid lubricants, including, but not limited to, 

heavy gear lubricants and automatic transmission fluids (automotive).[3.30] 

M 

m3

/h. Cubic meters per hour.[3.33] 

main-weighbeam elements. The combination of a main bar and its fractional bar, or a main bar alone if no fractional bar 

is associated with it.[2.20] 

main bar. A principal weighbeam bar, usually of relatively large capacity as compared with other bars of the same 

weighbeam. (On an automatic-indicating scale equipped with a weighbeam, the main weighbeam bar is frequently called 

the "capacity bar.")[2.20] 

main graduation. A graduation defining the primary or principal subdivisions of a graduated series. (Also see 

"graduation.")[1.10] 

manual zero-setting mechanism. Nonautomatic means provided to attain a zero balance indication by the direct 

operation of a control.[2.20] 

manufactured device. Any commercial weighing or measuring device shipped as new from the original equipment 

manufacturer.[1.10] 

(Amended 2001) 

mass flow meter. A device that measures the mass of a product flowing through the system. The mass measurement 

may be determined directly from the effects of mass on the sensing unit or may be inferred by measuring the properties of 

the product, such as the volume, density, temperature, or pressure, and displaying the quantity in mass units.[3.37] 

master meter test method. A method of testing milk tanks that utilizes an approved master meter system for measuring 

test liquid removed from or introduced into the tank.[4.42] 

master weight totalizer. An indicating element used with a belt-conveyor scale to indicate the weight of material that 

was passed over the scale. The master weight totalizer is a primary indicating element of the belt-conveyor scale.[2.21] 

material test. The test of a belt-conveyor scale using material (preferably that for which the device is normally used) that 

has been weighed to an accuracy of 0.1 %.[2.21] 

(Amended 1989) 

maximum capacity. The largest load that may be accurately weighed.[2.20, 2.24] 

(Added 1999) 

maximum cargo load. The maximum cargo load for trucks is the difference between the manufacturer's rated gross 

vehicle weight and the actual weight of the vehicle having no cargo load.[5.53] 

measuring element. That portion of a complete multiple dimension measuring device that does not include the 

indicating element.[5.58] 

measurement field. A region of space or the measurement pattern produced by the measuring instrument in which 

objects are placed or passed through, either singly or in groups, when being measured by a single device.[5.58] 

D-11 
Appendix D – Definitions Handbook 44 - 2008 

meter register. An observation index for the cumulative reading of the gas flow through the meter. In addition there are 

one or two proving circles in which one revolution of the test hand represents 1⁄2, 1, 2, 5, or 10 cubic feet, or 0.025, 0.05, 

0.1, 0.2, or 0.25 cubic meter, depending on meter size. If two proving circles are present, the circle representing the 

smallest volume per revolution is referred to as the "leak-test circle."[3.33] 

metrological integrity (of a device). The design, features, operation, installation, or use of a device that facilitates 

(1) the accuracy and validity of a measurement or transaction, (2) compliance of the device with weights and measures 

requirements, or (3) the suitability of the device for a given application.[1.10, 2.20] 

(Added 1993) 

minimum capacity. The smallest load that may be accurately weighed. The weighing results may be subject to 

excessive error if used below this value.[2.20, 2.24] 

(Added 1999) 

minimum clear interval. The shortest distance between adjacent graduations when the graduations are not parallel. 

(Also see "clear interval.")[3.30, 3.31, 3.32, 3.33, 3.34, 3.35, 3.36, 3.38, 5.50, 5.51, 5.56(b)] 

minimum delivery. The least amount of weight that is to be delivered as a single weighment by a belt-conveyor scale 

system in normal use.[2.21] 

minimum tolerance. Minimum tolerances are the smallest tolerance values that can be applied to a scale. Minimum 

tolerances are determined on the basis of the value of the minimum graduated interval or the nominal or reading face 

capacity of the scale. (See also definition for basic tolerances.)[2.20, 2.22, 2.24] 

minimum totalized load. The least amount of weight for which the scale is considered to be performing 

accurately.[2.21] 

moisture content (wet basis). The mass of water in a grain or seed sample (determined by the reference method) divided 

by the mass of the grain or seed sample expressed as a percentage (%).[5.56(a), 5.56(b)] 

money-operated type. A device designed to be released for service by the insertion of money, or to be actuated by the 

insertion of money to make deliveries of product.[1.10] 

money drop. An increment of fare indication. The "initial money drop" is the first increment of fare indication 

following activation of the taximeter.[5.54] 

motor-fuel device or motor-fuel dispenser or retail motor-fuel device. A device designed for the measurement and 

delivery of liquids used as fuel for internal-combustion engines. The term "motor-fuel dispenser" means the same as 

"motor-fuel device"; the term "retail motor-fuel device" applies to a unique category of device (see definition of "retail 

device").[3.30, 3.32, 3.37] 

motor-fuel. Liquid used as fuel for internal-combustion engines.[3.30] 

multi-class. A description of a grouping of grain classes, from the same grain type, in one calibration. A multi-class 

grain calibration may include (1) all the classes of a grain type (all-class calibration), or (2) some of the classes of a grain 

type within the calibration.[5.56(a), 5.57.] 

(Added 2007) 

multi-interval scale. A scale having one weighing range which is divided into partial weighing ranges (segments), each 

with different scale intervals, with each partial weighing range (segment) determined automatically according to the load 

applied, both on increasing and decreasing loads.[2.20] 

(Added 1995) 

multi-jet water meter. A water meter in which the moving element takes the form of a multiblade rotor mounted on a 

vertical spindle within a cylindrical measuring chamber. The liquid enters the measuring chamber through several 

tangential orifices around the circumference and leaves the measuring chamber through another set of tangential orifices 

placed at a different level in the measuring chamber. These meters register by recording the revolutions of a rotor set in 

motion by the force of flowing water striking the blades.[3.36] 

D-12 
Handbook 44 - 2008 Appendix D – Definitions 

(Added 2003) 

multi-revolution scale. An automatic-indicating scale having a nominal capacity that is a multiple of the reading-face 

capacity and that is achieved by more than one complete revolution of the indicator.[2.20] 

multiple cell application load cell. A load cell intended for use in a weighing system which incorporates more than one 

load cell. A multiple cell application load cell is designated with the letter "M" or the term "Multiple." (See also “single 

cell application load cell”)[2.20] 

(Added 1999) 

multiple of a scale. In general, the multiplying power of the entire system of levers or other basic weighing elements. 

(On a beam scale, the multiple of the scale is the number of pounds on the load-receiving element that will be counterpoised by 1 pound applied to the tip pivot of the weighbeam.)[2.20] 

multiple range scale. A scale having two or more weighing ranges with different maximum capacities and different 

scale intervals for the same load receptor, each range extending from zero to its maximum capacity.[2.20] 

(Added 1995) 

multiple-tariff taximeter. One that may be set to calculate fares at any one of two or more rates.[5.54] 

multiple. An integral multiple; that is, a result obtained by multiplying by a whole number. (Also see "multiple of a 

scale.")[1.10] 

N 

natural gas. A gaseous fuel, composed primarily of methane, that is suitable for compression and dispensing into a fuel 

storage container(s) for use as an engine fuel.[3.37] 

(Added 1994) 

NBP. Normal Boiling Point of a cryogenic liquid at 14.696 lb/in2

 absolute.[3.34] 

nmax (maximum number of scale divisions). The maximum number of scale divisions for which a main element or load 

cell complies with the applicable requirements. The maximum number of scale divisions permitted for an installation is 

limited to the lowest nmax marked on the scale indicating element, weighing element, or load cell.[2.20, 2.21, 2.24] 

(Added 1997) 

no-load reference value. A positive weight value indication with no load in the load-receiving element (hopper) of the 

scale. (Used with automatic bulk-weighing systems and certain single-draft, manually-operated receiving hopper scales 

installed below grade and used to receive grain.)[2.20] 

nominal capacity. The nominal capacity of a scale is (a) the largest weight indication that can be obtained by the use of 

all of the reading or recording elements in combination, including the amount represented by any removable weights 

furnished or ordinarily furnished with the scale, but excluding the amount represented by any extra removable weights not 

ordinarily furnished with the scale, and excluding also the capacity of any auxiliary weighing attachment not 

contemplated by the original design of the scale, and excluding any fractional bar with a capacity less than 21⁄2 % of the 

sum of the capacities of the remaining reading elements, or (b) the capacity marked on the scale by the manufacturer, 

whichever is less. (Also see "nominal capacity, batching scale"; "nominal capacity, hopper scale.")[2.20] 

nominal capacity, batching scale. The nominal capacity of a batching scale is the capacity as marked on the scale by the 

scale manufacturer, or the sum of the products of the volume of each of the individual hoppers, in terms of cubic feet, 

times the weight per cubic foot of the heaviest material weighed in each hopper, whichever is less.[2.20] 

nominal capacity, hopper scale. The nominal capacity of a hopper scale is the capacity as marked on the scale by the 

scale manufacturer, or the product of the volume of the hopper in bushels or cubic feet times the maximum weight per 

bushel or cubic foot, as the case may be, of the commodity normally weighed, whichever is less.[2.20] 

nominal. Refers to "intended" or "named" or "stated," as opposed to "actual." For example, the "nominal" value of something 

is the value that it is supposed or intended to have, the value that it is claimed or stated to have, or the value by which it is 

D-13 
Appendix D – Definitions Handbook 44 - 2008 

commonly known. Thus, "1-pound weight," "1-gallon measure," "1-yard indication," and "500-pound scale" are statements of 

nominal values; corresponding actual values may be greater or lesser. (See nominal capacity of a scale)[1.10] 

non-automatic checkweigher. A weighing instrument that requires the intervention of an operator during the weighing process, 

used to subdivide items of different weights into one or more subgroups, such as identifying packages that have acceptable or 

unacceptable fill levels according to the value of the difference between their weight and a pre-determined set point.[2.24]

Notes: Determining the weighing result includes any intelligent action of the operator that affects the result, such as 

deciding and taking an action when an indication is stable or adjusting the weight of the weighed load. 

Deciding that the weighing result is acceptable means making a decision regarding the acceptance of each weighing 

result on observing the indication or releasing a print-out. The weighing process allows the operator to take an action 

which influences the weighing result in the case where the weighing result is not acceptable. 

(Added 2004) 

non-automatic weighing instrument. A weighing instrument or system that requires the intervention of an operator 

during the weighing process to determine the weighing result or to decide that it is acceptable.[2.20, 2.24] 

Notes: Determining the weighing result includes any intelligent action of the operator that affects the result, such as 

deciding and taking an action when an indication is stable or adjusting the weight of the weighed load. 

Deciding that the weighing result is acceptable means making a decision regarding the acceptance of each weighing 

result on observing the indication or releasing a print-out. The weighing process allows the operator to take an action 

which influences the weighing result in the case where the weighing result is not acceptable. 

(Added 2004) (Amended 2005)

nonretroactive. "Nonretroactive" requirements are enforceable after the effective date for: 

1. devices manufactured within a state after the effective date; 

2. both new and used devices brought into a state after the effective date; and 

3. devices used in noncommercial applications which are placed into commercial use after the effective date. 

Nonretroactive requirements are not enforceable with respect to devices that are in commercial service in the state as of 

the effective date or to new equipment in the stock of a manufacturer or a dealer in the state as of the effective date. 

(Nonretroactive requirements are printed in italic type.)[1.10] 

(Amended 1989) 

nose-iron. A slide-mounted, manually-adjustable pivot assembly for changing the multiple of a lever.[2.20] 

notes. A section included in each of a number of codes, containing instructions, pertinent directives, and other specific 

information pertaining to the testing of devices. Notes are primarily directed to weights and measures officials.[1.10] 

NTP density and volume correction factor. A correction factor used to adjust the liquid volume of a cryogenic product 

at the time of measurement to the gas equivalent at NTP.[3.34] 

NTP. Normal Temperature and Pressure of a cryogen at a temperature of 21 °C (70 °F) and a pressure of 101.325 kPa 

(14.696 lb/in2

 absolute).[3.34] 

O 

odometer. A device that automatically indicates the total distance traveled by a vehicle. For the purpose of this code, 

this definition includes hub odometers, cable-driven odometers, and the distance-indicating or odometer portions of 

"speedometer" assemblies for automotive vehicles.[5.53] 

D-14 
Handbook 44 - 2008 Appendix D – Definitions 

official grain samples. Grain or seed used by the official as the official transfer standard from the reference standard 

method to test the accuracy and precision of grain moisture meters.[5.56(a), 5.56(b)] 

official with statutory authority. The representative of the jurisdiction(s) responsible for certifying the accuracy of the 

device.[2.20, 2.21, 2.22] 

(Added 1991) 

operating tire pressure. The pressure in a tire immediately after a vehicle has been driven for at least 5 miles or 

8 kilometers.[5.53, 5.54] 

over-and-under indicator. An automatic-indicating element incorporated in or attached to a scale and comprising an 

indicator and a graduated scale with a central or intermediate "zero" graduation and a limited range of weight graduations 

on either side of the zero graduation, for indicating weights greater than and less than the predetermined values for which 

other elements of the scale may be set. (A scale having an over-and-under indicator is classed as an automatic-indicating 

scale.)[2.20] 

overregistration and underregistration. When an instrument or device is of such a character that it indicates or records 

values as a result of its operation, its error is said to be in the direction of overregistration or underregistration, depending 

upon whether the indications are, respectively, greater or less than they should be. Examples of devices having errors of 

"overregistration" are: a fabric-measuring device that indicates more than the true length of material passed through it; 

and a liquid-measuring device that indicates more than the true amount of the liquid delivered by the device. Examples of 

devices having errors of "underregistration" are: a meter that indicates less than the true amount of product that it 

delivers; and a weighing scale that indicates or records less than the true weight of the applied load.[1.10] 

P 

parallax. The apparent displacement, or apparent difference in height or width, of a graduation or other object with 

respect to a fixed reference, as viewed from different points.[1.10] 

parking meter. A coin-operated device for measuring parking time for vehicles.[5.55] 

passenger vehicles. Vehicles such as automobiles, recreational vehicles, limousines, ambulances, and hearses.[5.53] 

performance requirements. Performance requirements include all tolerance requirements and, in the case of 

nonautomatic-indicating scales, sensitivity requirements (SR). (See definitions for "tolerance" and "sensitivity 

requirement.")[1.10] 

point-of-sale system. An assembly of elements including a weighing or measuring element, an indicating element, and a 

recording element (and may also be equipped with a “scanner”) used to complete a direct sales transaction.[2.20, 3.30, 

3.32, 3.37] 

(Added 1986) (Amended 1997) 

poise. A movable weight mounted upon or suspended from a weighbeam bar and used in combination with graduations, 

and frequently with notches, on the bar to indicate weight values. (A suspended poise is commonly called a "hanging 

poise.")[2.20] 

postal scale. A scale (usually a computing scale) designed for use to determine shipping weight or delivery charges for 

letters or parcels delivered by the U. S. Postal Service or private shipping companies. A weight classifier may be used as 

a postal scale.[2.20] 

(Added 1987) 

prepackaging scale. A computing scale specially designed for putting up packages of random weights in advance of 

sale.[2.20] 

prescription scale. A scale or balance adapted to weighing the ingredients of medicinal and other formulas prescribed by 

physicians and others and used or intended to be used in the ordinary trade of pharmacists.[2.20] 

D-15 
Appendix D – Definitions Handbook 44 - 2008 

pressure type (device). A type of device designed for operation with the liquid under artificially produced 

pressure.[3.30, 3.31] 

primary indicating or recording elements. The term "primary" is applied to those principal indicating (visual) elements 

and recording elements that are designed to, or may, be used by the operator in the normal commercial use of a device. 

The term "primary" is applied to any element or elements that may be the determining factor in arriving at the sale 

representation when the device is used commercially. (Examples of primary elements are the visual indicators for meters 

or scales not equipped with ticket printers or other recording elements and both the visual indicators and the ticket printers 

or other recording elements for meters or scales so equipped.) The term "primary" is not applied to such auxiliary 

elements as, for example, the totalizing register or predetermined-stop mechanism on a meter or the means for producing 

a running record of successive weighing operations, these elements being supplementary to those that are the determining 

factors in sales representations of individual deliveries or weights. (See "indicating element" and "recording 

element.")[1.10] 

prover oil. A light oil of low vapor pressure used as a sealing medium in bell provers, cubic-foot bottles, and portable 

cubic-foot standards.[3.33] 

proving indicator. The test hand or pointer of the proving or leak-test circle on the meter register or index.[3.33] 

prover method. A method of testing milk tanks that utilizes approved volumetric prover(s) for measuring the test liquid 

removed from or introduced into the tank.[4.42] 

R 

“r” factor. A computation for determining the suitability of a vehicle scale for weighing vehicles with varying axle 

configurations. The factor was derived by dividing the weights in FHWA Federal Highway Bridge Gross Weight 

Table B by 34 000 lbs. (The resultant factors contained in Table UR.3.2.1.)[2.20] 

radio frequency interference (RFI). Radio frequency interference is a type of electrical disturbance that, when 

introduced into electronic and electrical circuits, may cause deviations from the normally expected performance.[1.10] 

random error(s). The sample standard deviation of the error (indicated values) for a number of consecutive automatic 

weighings of a load, or loads, passed over the load receptor, shall be expressed mathematically as: 

( ) ( )2 2 2 1

1

1

1

 or i X X

n n

X X i i n s s −

− −

⎛ ⎞ ⎜ ⎟ ⎝ ⎠

∑ = −= ∑ ∑

where: X = error of a load indication 

 n = the number of loads 

[2.24] 

ranges, weight. See "weight ranges."[2.20] 

rated scale capacity. That value representing the weight that can be delivered by the device in one hour.[2.21] 

rated capacity. The rate of flow in cubic meters per hour of a hydrocarbon gas vapor-measuring device as recommended 

by the manufacturer. This rate of flow should cause a pressure drop across the meter not exceeding 1⁄2-inch water 

column.[3.33] 

ratio test. A test to determine the accuracy with which the actual multiple of a scale agrees with its designed multiple. 

This test is used for scales employing counterpoise weights and is made with standard test weights substituted in all cases 

for the weights commercially used on the scale. (It is appropriate to use this test for some scales not employing 

counterpoise weights.)[2.20] 

reading-face capacity. The largest value that may be indicated on the reading face, exclusive of the application or 

addition of any supplemental or accessory elements.[1.10] 

D-16 
Handbook 44 - 2008 Appendix D – Definitions 

reading face. That portion of an automatic-indicating weighing or measuring device that gives a visible indication of the 

quantity weighed or measured. A reading face may include an indicator and a series of graduations or may present values 

digitally, and may also provide money-value indications.[1.10, 2.20] 

(Amended 2005) 

recorded representation. The printed, embossed, or other representation that is recorded as a quantity by a weighing or 

measuring device.[1.10] 

recording element. An element incorporated in a weighing or measuring device by means of which its performance 

relative to quantity or money value is permanently recorded on a tape, ticket, card, or the like, in the form of a printed, 

stamped, punched, or perforated representation.[1.10, 2.21] 

recording scale. One on which the weights of applied loads may be permanently recorded on a tape, ticket, card, or the 

like in the form of a printed, stamped, punched, or perforated representation.[2.20] 

reference weight car. A railroad car weighed on a scale for temporary use as a mass standard over a short period of time 

(typically, the time required to test one scale) as part of a test train. 

Note: A test weight car that is representative of the types of cars typically weighed on the scale under test may be 

used wherever reference weight cars are specified.[2.20] 

(Added 1991) 

remanufactured device. A device that is disassembled, checked for wear, parts replaced or fixed, reassembled and made 

to operate like a new device of the same type.[1.10] 

(Added 2001) 

remanufactured element. An element that is disassembled, checked for wear, parts replaced or fixed, reassembled and 

made to operate like a new element of the same type.[1.10] 

(Added 2001) 

repaired device. A device to which work is performed that brings the device back into proper operating condition.[1.10] 

(Added 2001) 

repaired element. An element to which work is performed that brings the element back into proper operating 

condition.[1.10] 

(Added 2001) 

remote configuration capability. The ability to adjust a weighing or measuring device or change its sealable parameters 

from or through some other device that is not itself necessary to the operation of the weighing or measuring device or is 

not a permanent part of that device.[2.20, 2.21, 2.24, 3.30, 3.37, 5.56(a)] 

(Added 1993) 

retail device. A measuring device primarily used to measure product for the purpose of sale to the end user.[3.30, 3.32, 

3.37] 

(Amended 1987 and 2004) 

retroactive. "Retroactive" requirements are enforceable with respect to all equipment. Retroactive requirements are 

printed herein in upright roman type. (Also see "nonretroactive.")[1.10] 

road test. A distance test, over a measured course, of a complete taximeter assembly when installed on a vehicle, the 

mechanism being actuated as a result of vehicle travel.[5.53, 5.54] 

rolling circumference. The rolling circumference is the straight line distance traveled per revolution of the wheel (or 

wheels) that actuates the taximeter or odometer. If more than one wheel actuates the taximeter or odometer, the rolling 

circumference is the average distance traveled per revolution of the actuating wheels.[5.53, 5.54] 

D-17 
Appendix D – Definitions Handbook 44 - 2008 

S 

scale area, belt-conveyor. See belt-conveyor scale systems area.[2.21] 

(Added 2001) 

scale division, number of (n). Quotient of the capacity divided by the value of the verification scale division.[2.20] 

 e

Capacity n = 

scale division, value of (d). The value of the scale division, expressed in units of mass, is the smallest subdivision of the 

scale for analog indication or the difference between two consecutively indicated or printed values for digital indication or 

printing. (Also see "verification scale division.")[2.20, 2.22] 

 

scale section. A part of a vehicle, axle-load, livestock, or railway track scale consisting of two main load supports, 

usually transverse to the direction in which the load is applied.[2.20] 

scale. See specific type of scale.[2.20] 

seal. See "approval seal," "security seal."[1.10] 

section capacity. The section capacity of a scale is the maximum live load that may be divided equally on the load pivots 

or load cells of a section.[2.20] 

(Added 2001) 

section test. A shift test in which the test load is applied over individual sections of the scale. This test is conducted to 

disclose the weighing performance of individual sections, since scale capacity test loads are not always available and 

loads weighed are not always distributed evenly over all main load supports.[2.20] 

security means. A method used to prevent access by other than qualified personnel, or to indicate that access has been 

made to certain parts of a scale that affect the performance of the device.[2.21] 

security seal. A uniquely identifiable physical seal, such as a lead-and-wire seal or other type of locking seal, a 

pressure-sensitive seal sufficiently permanent to reveal its removal, or similar apparatus attached to a weighing or 

measuring device for protection against or indication of access to adjustment. (Also see "approval seal.")[1.10] 

(Amended 1994) 

selector-type. A system of indication or recording in which the mechanism selects, by means of a ratchet-and-pawl 

combination or by other means, one or the other of any two successive values that can be indicated or recorded.[1.10] 

semi-automatic zero-setting mechanism. Automatic means provided to attain a direct zero balance indication requiring 

a single initiation by an operator.[2.20] 

sensitivity requirement (SR). A performance requirement for a non automatic-indicating scale; specifically, the 

minimum change in the position of rest of the indicating element or elements of the scale in response to the increase or 

decrease, by a specified amount, of the test load on the load-receiving element of the scale.[2.20] 

sensitivity (of a nonautomatic-indicating scale). The value of the test load on the load-receiving element of the scale 

that will produce a specified minimum change in the position of rest of the indicating element or elements of the 

scale.[2.20] 

shift test. A test intended to disclose the weighing performance of a scale under off-center loading.[2.20] 

side. That portion of a pump or dispenser which faces the consumer during the normal delivery of product.[3.30] 

(Added 1987) 

D-18 
Handbook 44 - 2008 Appendix D – Definitions 

simulated-road test. A distance test during which the taximeter or odometer may be actuated by some means other than 

road travel. The distance traveled is either measured by a properly calibrated roller device or computed from rolling 

circumference and wheel-turn data.[5.53, 5.54] 

simulated test. A test using artificial means of loading the scale to determine the performance of a belt-conveyor 

scale.[2.21] 

single cell application load cell. A load cell intended for use in a weighing system which incorporates one or more load 

cells. A single cell application load cell is designated with the letter "S" or the term "Single." (See also “multiple cell 

application load cell”)[2.20] 

(Added 1999) 

single-tariff taximeter. One that calculates fares at a single rate only.[5.54] 

skirting. Stationary side boards or sections of belt conveyor attached to the conveyor support frame or other stationary 

support to prevent the bulk material from falling off the side of the belt.[2.21] 

slow-flow meter. A retail device designed for the measurement, at very slow rates (less than 40 L (10 gal) per hour), of 

liquid fuels at individual domestic installations.[3.30] 

small-delivery device. Any device other than a large-delivery device.[3.34, 3.38] 

span (structural). The distance between adjoining sections of a scale.[2.20] 

(Added 1988) 

specification. A requirement usually dealing with the design, construction, or marking of a weighing or measuring 

device. Specifications are directed primarily to the manufacturers of devices.[1.10] 

static monorail weighing system. A weighing system in which the load being applied is stationary during the weighing 

operation.[2.20] 

(Added 1999) 

strain-load test. The test of a scale beginning with the scale under load and applying known test weights to determine 

accuracy over a portion of the weighing range. The scale errors for a strain-load test are the errors observed for the 

known test loads only. The tolerances to be applied are based on the known test load used for each error that is 

determined.[2.20, 2.22] 

subordinate graduation. Any graduation other than a main graduation. (Also see "graduation.")[1.10] 

subsequent distance or time intervals. The intervals corresponding to money drops following the initial money 

drop.[5.54] 

substitution test. A scale testing process used to quantify the weight of material or objects for use as a known test load.[2.20] 

(Added 2003) 

substitution test load. The sum of the combination of field standard test weights and any other applied load used in the 

conduct of a test using substitution test methods.[2.20] 

(Added 2003) 

surface gauge. A combination of (1) a stationary indicator, and (2) a movable, graduated element designed to be brought 

into contact with the surface of the liquid from above.[4.42] 

systematic (average) error ( ) X . The mean value of the error (of indication) for a number of consecutive automatic 

weighings of a load, or loads, passed over the load-receiving element (e.g., weigh-table), shall be expressed 

mathematically as: 

X

X

n = ∑

D-19 
Appendix D – Definitions Handbook 44 - 2008 

where: x = error of a load indication 

n = the number of loads 

[2.24] 

T 

tail pulley. The pulley at the opposite end of the conveyor from the head pulley.[2.21] 

take-up. A device to provide sufficient tension in a conveyor belt so that the belt will be positively driven by the drive 

pulley. A counter-weighted take-up consists of a pulley free to move in either the vertical or horizontal direction with 

dead weights applied to the pulley shaft to provide the tension required.[2.21] 

tare-weighbeam elements. The combination of a tare bar and its fractional bar, or a tare bar alone if no fractional bar is 

associated with it.[2.20] 

tare mechanism. A mechanism (including a tare bar) designed for determining or balancing out the weight of packaging 

material, containers, vehicles, or other materials that are not intended to be included in net weight determinations.[2.20] 

taximeter. A device that automatically calculates, at a predetermined rate or rates, and indicates the charge for hire of a 

vehicle.[5.54] 

testing. An operation consisting of a series of volumetric determinations made to verify the accuracy of the volume chart 

that was developed by gauging.[4.42] 

test chain. A device used for simulated tests consisting of a series of rollers or wheels linked together in such a manner as to 

assure uniformity of weight and freedom of motion to reduce wear, with consequent loss of weight, to a minimum.[2.21] 

test liquid. The liquid used during the test of a device.[3.30, 3.31, 3.34, 3.35, 3.36, 3.37, 3.38] 

test object. An object whose dimensions are verified by appropriate reference standards and intended to verify 

compliance of the device under test with certain metrological requirements.[5.58] 

test puck. A metal, plastic, or other suitable object that remains stable for the duration of the test, used as a test load to simulate 

a package. Pucks can be made in a variety of dimensions and have different weights to represent a wide range of package sizes. 

Metal versions may be covered with rubber cushions to eliminate the possibility of damage to weighing and handling 

equipment. The puck mass is adjusted to an accuracy specified in N.1.2. Accuracy of Test Pucks or Packages.[2.24] 

(Amended 2004) 

test train. A train consisting of or including reference weight cars and used to test coupled-in-motion railway track 

scales. The reference weight cars may be placed consecutively or distributed in different places within a train.[2.20] 

(Added 1990) (Amended 1991) 

test weight car. A railroad car designed to be a stable mass standard to test railway track scales. The test weight car may 

be one of the following types: a self-contained composite car, a self-propelled car, or a standard rail car.[2.20] 

(Added 1991) 

time recorder. A clock-operated mechanism designed to record the time of day. Examples of time recorders are those 

used in parking garages to record the "in" and "out" time of day for parked vehicles.[5.55] 

timing device. A device used to measure the time during which a particular paid-for service is dispensed. Examples of 

timing devices are laundry driers, car-wash timers, parking meters, and parking-garage clocks and recorders.[5.55] 

tolerance. A value fixing the limit of allowable error or departure from true performance or value. (See also "basic 

tolerances.")[1.10] 

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Handbook 44 - 2008 Appendix D – Definitions 

training idlers. Idlers of special design or mounting intended to shift the belt sideways on the conveyor to assure the belt 

is centered on the conveying idlers.[2.21] 

transfer standard. A measurement system designed for use in proving and testing cryogenic liquid-measuring 

devices.[3.38] 

tripper. A device for unloading a belt conveyor at a point between the loading point and the head pulley.[2.21] 

U 

uncoupled-in-motion railroad weighing system. A device and related installation characteristics consisting of (1) the 

associated approach trackage, (2) the scale (i.e., the weighing element, the load-receiving element, and the indicating 

element with its software), and (3) the exit trackage which permit the weighing of railroad cars uncoupled in 

motion.[2.20] 

(Added 1993) 

underregistration. See "overregistration" and "underregistration."[1.10] 

unit price. The price at which the product is being sold and expressed in whole units of measurement.[1.10, 3.30] 

(Added 1992) 

unit weight. One contained within the housing of an automatic-indicating scale and mechanically applied to and 

removed from the mechanism. The application of a unit weight will increase the range of automatic indication, normally 

in increments equal to the reading-face capacity.[2.20] 

unit train. A unit train is defined as a number of contiguous cars carrying a single commodity from one consignor to one 

consignee. The number of cars is determined by agreement among the consignor, consignee, and the operating 

railroad.[2.20] 

user requirement. A requirement dealing with the selection, installation, use, or maintenance of a weighing or 

measuring device. User requirements are directed primarily to the users of devices.[1.10] 

usual and customary. Commonly or ordinarily found in practice or in the normal course of events and in accordance 

with established practices.[1.10] 

V 

value of minimum graduated interval. The value represented by the interval from the center of one graduation to the 

center of the succeeding graduation. Also, the increment between successive recorded values. (Also see "graduated 

interval.")[1.10] 

vapor equalization credit. The quantity deducted from the metered quantity of liquid carbon dioxide when a vapor 

equalizing line is used to facilitate the transfer of liquid during a metered delivery.[3.38] 

vapor equalization line. A hose or pipe connected from the vapor space of the seller's tank to the vapor space of the 

buyer's tank that is used to equalize the pressure during a delivery.[3.38] 

vehicle on-board weighing system. A weighing system designed as an integral part of or attached to the frame, chassis, 

lifting mechanism, or bed of a vehicle, trailer, industrial truck, industrial tractor, or forklift truck.[2.20] 

(Amended 1993) 

vehicle scale. A scale adapted to weighing highway, farm, or other large industrial vehicles (except railroad freight cars), 

loaded or unloaded.[2.20] 

verification scale division, value of (e). A value, expressed in units of weight (mass) and specified by the manufacturer 

of a device, by which the tolerance values and the accuracy class applicable to the device are determined. The 

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Appendix D – Definitions Handbook 44 - 2008 

verification scale division is applied to all scales, in particular to ungraduated devices since they have no graduations. 

The verification scale division, e, may be different from the displayed scale division, d, for certain other devices used for 

weight classifying or weighing in pre-determined amounts, and certain other Class I and II scales.[2.20] 

visible type. A type of device in which the measurement takes place in a see-through glass measuring chamber.[3.30] 

vmin (minimum load cell verification interval). The smallest load cell verification interval, expressed in units of mass*

into which the load cell measuring range can be divided.[2.20, 2.24] 

[*Nonretroactive as of January 1, 2001]

(Added 1996) (Amended 1999) 

W 

weigh-labeler. An automatic weighing system that determines the weight of a package and prints a label or other 

document bearing a weight declaration for each discrete item (usually a label also includes unit and total price 

declarations). Weigh-labelers are sometimes used to weigh and label standard and random packages (also called 

"Prepackaging Scales").[2.24] 

(Amended 2004) 

weighbeam. An element comprising one or more bars, equipped with movable poises or means for applying 

counterpoise weights or both.[2.20] 

weighing element. That portion of a scale that supports the load-receiving element and transmits to the indicating 

element a signal or force resulting from the load applied to the load-receiving element.[2.20, 2.21, 2.22] 

(Added 1988) 

weighment. A single complete weighing operation.[2.20, 2.21] 

(Added 1986) 

weight, unit. See "unit weight."[2.20] 

weight classifier. A digital scale that rounds weight values up to the next scale division. These scales usually have a 

verification scale division, e, that is smaller than the displayed scale division.[2.20] 

(Added 1987) 

weight ranges. Electrical or electro-mechanical elements incorporated in an automatic indicating scale through the 

application of which the range of automatic indication of the scale is increased, normally in increments equal to the 

reading-face capacity.[2.20] 

wet basis. See "moisture content (wet basis)."[5.56(a), 5.56(b)] 

wet hose. A discharge hose intended to be full of product at all times. (See "wet-hose type.")[3.30, 3.31, 3.38] 

(Amended 2002) 

wet-hose type. A type of device designed to be operated with the discharge hose full of product at all times. (See "wet 

hose.")[3.30, 3.32, 3.34, 3.37, 3.38] 

(Amended 2002) 

wheel-load weighers. Compact, self-contained, portable weighing elements specially adapted to determining the wheel 

loads or axle loads of vehicles on highways for the enforcement of highway weight laws only.[2.20] 

wholesale device. Any device other than a retail device. (See "retail device.")[3.30, 3.32] 

wing pulley. A pulley made of widely spaced metal bars in order to set up a vibration to shake loose material off the 

underside (return side) of the belt.[2.21] 

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Handbook 44 - 2008 Appendix D – Definitions 

Z 

zero-load balance. A correct weight indication or representation of zero when there is no load on the load-receiving 

element. (See also "zero-load balance for an automatic-indicating scale," "zero-load balance for a nonautomatic-indicating scale," "zero-load balance for a recording scale.")[2.20] 

zero-load balance, automatic-indicating scale. A condition in which the indicator is at rest at, or oscillates through 

approximately equal arcs on either side of, the zero graduation.[2.20] 

zero-load balance, nonautomatic-indicating scale. A condition in which (a) the weighbeam is at rest at, or oscillates 

through approximately equal arcs above and below, the center of a trig loop; (b) the weighbeam or lever system is at rest 

at, or oscillates through approximately equal arcs above and below, a horizontal position or a position midway between 

limiting stops; or (c) the indicator of a balance indicator is at rest at, or oscillates through approximately equal arcs on 

either side of, the zero graduation.[2.20] 

zero-load balance for a recording scale. A condition in which the scale will record a representation of zero load.[2.20] 

zero-load reference (belt-conveyor scales). A zero-load reference value represents no load on a moving conveyor belt. 

This value can be either; a number representing the electronic load cell output, a percentage of full scale capacity, or other 

reference value that accurately represents the no load condition of a moving conveyor belt. The no load reference value 

can only be updated after the completion of a zero load test.[2.21] 

(Added 2002) 

zero-setting mechanism. Means provided to attain a zero balance indication with no load on the load-receiving element. 

Three types of these mechanisms are:[2.20] 

automatic zero-tracking mechanism. Automatic means provided to maintain the zero balance indication, within 

certain limits, without the intervention of an operator.[2.20, 2.22, 2.24] 

manual zero-setting mechanism. Nonautomatic means provided to attain a zero balance indication by the direct 

operation of a control.[2.20] 

semiautomatic zero-setting mechanism. Automatic means provided to attain a direct zero balance indication 

requiring a single initiation by an operator.[2.20] 

zero-setting mechanism (belt-conveyor scale). A mechanism enabling zero totalization to be obtained over a whole 

number of belt revolutions.[2.21, 2.23]

(Added 2002) 

zero-tracking mechanism. Automatic means provided to maintain zero balance indication without the intervention of an 

operator.[2.20] 

zone of uncertainty. The zone between adjacent increments on a digital device in which the value of either of the 

adjacent increments may be displayed.[2.20] 

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