Handbook 44 – 2010 3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices 

Table of Contents 

Section 3.32. Liquefied Petroleum Gas and Anhydrous Ammonia Liquid-Measuring 

Devices......................................................................................................... 3-45

A. Application. ................................................................................................................................................. 3-45

S. Specifications............................................................................................................................................... 3-45

S.1. Design of Indicating and Recording Elements and of Recorded Representations............................. 3-45

S.1.1. Primary Elements................................................................................................................. 3-45

S.1.2. Graduations.......................................................................................................................... 3-46

S.1.3. Indicators. ............................................................................................................................ 3-46

S.1.4. For Retail Devices Only....................................................................................................... 3-47

S.1.5. For Stationary Retail Devices Only. .................................................................................... 3-47

S.1.6. For Wholesale Devices Only. .............................................................................................. 3-48

S.2. Design of Measuring Elements.......................................................................................................... 3-48

S.2.1. Vapor Elimination................................................................................................................ 3-48

S.2.2. Provision for Sealing............................................................................................................ 3-49

S.2.3. Directional Flow Valves. ..................................................................................................... 3-50

S.2.4. Maintenance of Liquid State................................................................................................ 3-50

S.2.5. Thermometer Well............................................................................................................... 3-50

S.2.6. Automatic Temperature Compensation. .............................................................................. 3-50

S.3. Design of Discharge Lines and Discharge Line Valves..................................................................... 3-50

S.3.1. Diversion of Measured Liquid. ............................................................................................ 3-50

S.3.2. Delivery Hose. ..................................................................................................................... 3-50

S.4. Marking Requirements....................................................................................................................... 3-51

S.4.1. Limitation of Use................................................................................................................. 3-51

S.4.2. Discharge Rates. .................................................................................................................. 3-51

S.4.3. Location of Marking Information; Retail Motor-Fuel Dispensers....................................... 3-51

S.4.4. Temperature Compensation. ................................................................................................ 3-51

N. Notes............................................................................................................................................................. 3-51

N.1. Test Liquid......................................................................................................................................... 3-51

N.2. Vaporization and Volume Change..................................................................................................... 3-51

N.3. Test Drafts. ........................................................................................................................................ 3-51

N.4. Testing Procedures............................................................................................................................. 3-51

N.4.1. Normal Tests........................................................................................................................ 3-51

N.4.2. Special Tests. ....................................................................................................................... 3-52

N.4.3. Money-Value Computation Tests. ....................................................................................... 3-53

N.5. Temperature Correction..................................................................................................................... 3-53

T. Tolerances.................................................................................................................................................... 3-53

T.1. Application......................................................................................................................................... 3-53

T.1.1. To Underregistration and to Overregistration. ..................................................................... 3-53

T.2. Tolerance Values. .............................................................................................................................. 3-53

T.3. Repeatability. ..................................................................................................................................... 3-53

T.4. Automatic Temperature-Compensating Systems............................................................................... 3-54

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3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices Handbook 44 – 2010 

UR. User Requirements ..................................................................................................................................... 3-54

UR.1. Installation Requirements. ................................................................................................................. 3-54

UR.1.1. Discharge Rate..................................................................................................................... 3-54

UR.1.2. Length of Discharge Hose. .................................................................................................. 3-54

UR.2. Use Requirements. ............................................................................................................................. 3-54

UR.2.1. Return of Indication and Recording Elements to Zero. ....................................................... 3-54

UR.2.2. Condition of Fill of Discharge Hose.................................................................................... 3-54

UR.2.3. Vapor-Return Line............................................................................................................... 3-54

UR.2.4. Temperature Compensation. ................................................................................................ 3-54

UR.2.5. Ticket in Printing Device..................................................................................................... 3-55

UR.2.6. Ticket Printer; Customer Ticket........................................................................................... 3-55

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Handbook 44 – 2010 3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices 

Section 3.32. Liquefied Petroleum Gas and Anhydrous Ammonia LiquidMeasuring Devices1

A. Application. 

A.1. This code applies to devices used for the measurement of liquefied petroleum gas and anhydrous ammonia in 

the liquid state, whether such devices are installed in a permanent location or mounted on a vehicle. 

A.2. Insofar as they are clearly appropriate, the requirements and provisions of the code may be applied to devices 

used for the measurement of other liquids that do not remain in a liquid state at atmospheric pressures and 

temperatures. 

A.3. See also Section 1.10. General Code requirements. 

A.4. This code does not apply to mass flow meters (see Section 3.37. Code for Mass Flow Meters). 

(Added 1994) 

S. Specifications 

S.1. Design of Indicating and Recording Elements and of Recorded Representations. 

S.1.1. Primary Elements. 

S.1.1.1. General. – A device shall be equipped with a primary indicating element and may also be 

equipped with a primary recording element. 

Note: Vehicle-mounted metering systems shall be equipped with a primary recording element as required by 

paragraph UR.2.6. Ticket Printer; Customer Ticket. 

S.1.1.2. Units. – A device shall indicate, and record if the device is equipped to record, its deliveries in 

terms of liters, gallons, quarts, pints, or binary-submultiple or decimal subdivisions of the liter or gallon. 

(Amended 1987) 

S.1.1.3. Value of Smallest Unit. – The value of the smallest unit of indicated delivery, and recorded 

delivery if the device is equipped to record, shall not exceed the equivalent of: 

(a) 0.5 L (1 pt) on retail devices, or 

(b) 5 L (1 gal) on wholesale devices. 

(Amended 1987) 

S.1.1.4. Advancement of Indicating and Recording Elements. – Primary indicating and recording 

elements shall be susceptible to advancement only by the mechanical operation of the device. However, a 

device may be cleared by advancing its elements to zero, but only if: 

(a) the advancing movement, once started, cannot be stopped until zero is reached, or 

(b) in the case of indicating elements only, such elements are automatically obscured until the 

elements reach the correct zero position. 

 

1

Title amended 1986. 

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3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices Handbook 44 – 2010 

S.1.1.5. Money Values, Mathematical Agreement. – Any digital money-value indication and any 

recorded money value on a computing-type device shall be in mathematical agreement with its associated 

quantity indication or representation to within 1 cent of money value; except that a stationary retail 

computing-type device must compute and indicate to the nearest 1 cent of money value. (See Section 1.10. 

G-S.5.5. Money Values, Mathematical Agreement) 

(Amended 1984 and 1988) 

S.1.1.6. Printed Ticket. – Any printed ticket issued by a device of the computing type on which there is 

printed the total computed price, shall have printed clearly thereon the total volume of the delivery in terms 

of liters or gallons, and the appropriate decimal fraction of the liter or gallon, and the corresponding price 

per liter or gallon. 

(Added 1979) (Amended 1987) 

S.1.2. Graduations. 

S.1.2.1. Length. – Graduations shall be so varied in length that they may be conveniently read. 

S.1.2.2. Width. – In any series of graduations, the width of a graduation shall in no case be greater than 

the width of the minimum clear interval between graduations, and the width of main graduations shall be 

not more than 50 % greater than the width of subordinate graduations. Graduations shall in no case be less 

than 0.2 mm (0.008 in) in width. 

S.1.2.3. Clear Interval Between Graduations. – The clear interval shall be not less than 1.0 mm 

(0.04 in). If the graduations are not parallel, the measurement shall be made: 

(a) along the line of relative movement between the graduations at the end of the indicator, or 

(b) if the indicator is continuous, at the point of widest separation of the graduations. 

S.1.3. Indicators. 

S.1.3.1. Symmetry. – The index of an indicator shall be symmetrical with respect to the graduations, at 

least throughout that portion of its length associated with the graduations. 

S.1.3.2. Length. – The index of an indicator shall reach to the finest graduations with which it is used, 

unless the indicator and the graduations are in the same plane, in which case the distance between the end 

of the indicator and the ends of the graduations, measured along the line of graduations, shall be not more 

than 1.0 mm (0.04 in). 

S.1.3.3. Width. – The width of the index of an indicator in relation to the series of graduations with 

which it is used shall be not greater than: 

(a) the width of the narrowest graduation*, and 

[*Nonretroactive as of January 1, 2002]

(Amended 2001) 

(b) the width of the minimum clear interval between graduations. 

When the index of an indicator extends along the entire length of a graduation, that portion of the index of 

the indicator that may be brought into coincidence with the graduation shall be of the same width 

throughout the length of the index that coincides with the graduation. 

S.1.3.4. Clearance. – The clearance between the index of an indicator and the graduations shall in no 

case be more than 1.5 mm (0.06 in). 

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Handbook 44 – 2010 3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices 

S.1.3.5. Parallax. – Parallax effects shall be reduced to the practicable minimum. 

S.1.4. For Retail Devices Only. 

S.1.4.1. Indication of Delivery. – A retail device shall be constructed to show automatically its initial 

zero condition and the amounts delivered up to the nominal capacity of the device. 

S.1.4.2. Return to Zero.

(a) Primary indicating elements shall be readily returnable to a definite zero indication. 

(b) Primary recording elements on a stationary retail device shall be readily returnable to a definite 

zero indication if the device is equipped to record. 

(c) Means shall be provided to prevent the return of primary indicating elements, and of primary 

recording elements if these are returnable to zero, beyond their correct zero position. 

(Amended 1990) 

S.1.5. For Stationary Retail Devices Only. 

S.1.5.1. Display of Unit Price and Product Identity. – In a device of the computing type, means shall 

be provided for displaying on each face of the device the unit price at which the device is set to compute or 

to deliver as the case may be, and there shall be conspicuously displayed on each side of the device the 

identity of the product that is being dispensed. If a device is so designed as to dispense more than one 

grade, brand, blend, or mixture of product, the identity of the grade, brand, blend, or mixture being 

dispensed shall also be displayed on each face of the device. 

S.1.5.2. Money-Value Computations. – A computing device shall compute the total sales price at any 

single-purchase unit price (excluding fleet sales and other price contract sales) for which the product is 

offered for sale at any delivery possible within either the measurement range of the device or the range of 

the computing elements, whichever is less. The analog money value indication shall not differ from the 

mathematically computed money value (quantity x unit price = sales price), for any delivered quantity, by 

an amount greater than the values shown in Table 1. 

(Amended 1995) 

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3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices Handbook 44 – 2010 

Table 1. 

Money-Value Divisions and 

Maximum Allowable Variations for Money-Value 

Computations on Mechanical Analog Computers 

Unit Price Maximum 

Allowable Variation 

From To and Including 

Money 

Value 

Division Design 

Test 

Field 

Test 

0 $0.25/liter or 

$1.00/gallon 1¢ ± 1¢ ± 1¢ 

$0.25/liter or 

$1.00/gallon 

 $0.75/liter or 

 $3.00/gallon 1¢ or 2¢ ± 1¢ ± 2¢ 

$0.75/liter or 

$3.00/gallon 

 $2.50/liter or 

 $10.00/gallon 1¢ or 2¢ ± 1¢ ± 2¢ 

$0.75/liter or 

$3.00/gallon 

 $2.50/liter or 

 $10.00/gallon 5¢ ± 21⁄2¢ ± 5¢ 

S.1.5.2.1. Money-Value Divisions, Analog. – The value of the graduated intervals representing 

money values on a computing-type device with analog indications shall be as follows: 

(a) Not more than 1 cent at all unit prices up to and including $0.25 per liter or $1.00 per gallon. 

(b) Not more than 2 cents at unit prices greater than $0.25 per liter or $1.00 per gallon up to and 

including $0.75 per liter or $3.00 per gallon. 

(c) Not more than 5 cents at all unit prices greater than $0.75 per liter or $3.00 per gallon. 

(Amended 1984) 

S.1.5.2.2. Money-Value Divisions, Digital. – A computing-type device with digital indications 

shall comply with the requirements of paragraph G.-S.5.5. Money Values, Mathematical Agreement, 

and the total price computation shall be based on quantities not exceeding 0.01-gallon intervals for 

devices indicating in inch-pound units and 0.05 liter for devices indicating in metric units. 

S.1.5.2.3. Money-Value Divisions, Auxiliary Indications. – In a system equipped with auxiliary 

indications, all indicated money-value divisions shall be identical. 

[Nonretroactive as of January 1, 1985.]

S.1.6. For Wholesale Devices Only. 

S.1.6.1. Travel of Indicator. – A wholesale device shall be readily operable to deliver accurately any 

quantity from 180 L (50 gal) to the capacity of the device. If the most sensitive element of the indicating 

system uses an indicator and graduations, the relative movement of these parts corresponding to a delivery 

of 5 L (1 gal) shall be not less than 5 mm (0.20 in). 

(Amended 1987) 

S.2. Design of Measuring Elements. 

S.2.1. Vapor Elimination. – A device shall be equipped with an effective vapor eliminator or other effective 

means to prevent the passage of vapor through the meter. 

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Handbook 44 – 2010 3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices 

S.2.2. Provision for Sealing. – Adequate provision shall be made for an approved means of security 

(e.g., data change audit trail) or for physically applying a security seal in such a manner that requires the 

security seal to be broken before an adjustment or interchange may be made of: 

(a) any measuring or indicating element; 

(b) any adjustable element for controlling delivery rate, when such rate tends to affect the accuracy of 

deliveries; and 

(c) any metrological parameter that will affect the metrological integrity of the device or system. 

When applicable, the adjusting mechanism shall be readily accessible for purposes of affixing a security seal. 

[Audit trails shall use the format set forth in Table S.2.2. Categories of Device and Methods of Sealing.]* 

[*Nonretroactive as of January 1, 1995] 

(Amended 2006) 

Table S.2.2. 

Categories of Device and Methods of Sealing 

Categories of Device Methods of Sealing 

Category 1: No remote configuration capability. Seal by physical seal or two event counters: one for 

calibration parameters and one for configuration 

parameters. 

Category 2: Remote configuration capability, but access 

is controlled by physical hardware. 

The device shall clearly indicate that it is in the remote 

configuration mode and record such message if capable 

of printing in this mode or shall not operate while in this 

mode.

The hardware enabling access for remote communication 

must be on-site. The hardware must be sealed using a 

physical seal or an event counter for calibration 

parameters and an event counter for configuration 

parameters. The event counters may be located either at 

the individual measuring device or at the system 

controller; however, an adequate number of counters 

must be provided to monitor the calibration and 

configuration parameters of the individual devices at a 

location. If the counters are located in the system 

controller rather than at the individual device, means 

must be provided to generate a hard copy of the 

information through an on-site device.

Category 3: Remote configuration capability access may 

be unlimited or controlled through a software switch 

(e.g., password). 

The device shall clearly indicate that it is in the remote 

configuration mode and record such message if capable 

of printing in this mode or shall not operate while in this 

mode. 

An event logger is required in the device; it must include 

an event counter (000 to 999), the parameter ID, the date 

and time of the change, and the new value of the 

parameter. A printed copy of the information must be 

available through the device or through another on-site 

device. The event logger shall have a capacity to retain 

records equal to ten times the number of sealable 

parameters in the device, but not more than 1000 records 

are required. (Note: Does not require 1000 changes to 

be stored for each parameter.)

[Nonretroactive as of January 1, 1995]

(Table Added 2006) 

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3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices Handbook 44 – 2010 

S.2.3. Directional Flow Valves. – A measuring system shall be equipped with a valve or other effective 

means, automatic in operation and installed in or adjacent to the measuring element, to prevent reversal of flow 

of the product being measured. 

(Amended 1982) 

S.2.4. Maintenance of Liquid State. – A device shall be so designed and installed that the product being 

measured will remain in a liquid state during the passage through the meter. 

S.2.5. Thermometer Well. – For test purposes, means shall be provided to determine the temperature of the 

liquid either: 

(a) in the liquid chamber of the meter, or 

(b) in the meter inlet or discharge line and immediately adjacent to the meter. 

(Amended 1987) 

S.2.6. Automatic Temperature Compensation. – A device may be equipped with an adjustable automatic 

means for adjusting the indication and registration of the measured volume of product to the volume at 15 °C 

(60 °F). 

S.2.6.1. Provision for Deactivating. – On a device equipped with an automatic temperaturecompensating mechanism that will indicate or record only in terms of liters or gallons adjusted to 15 °C 

(60 °F), provision shall be made to facilitate the deactivation of the automatic temperature-compensating 

mechanism so that the meter may indicate, and record if it is equipped to record, in terms of the 

uncompensated volume. 

(Amended 1972) 

S.2.6.2. Provision for Sealing. – Provision shall be made for applying security seals in such a manner 

that an automatic temperature-compensating system cannot be disconnected and that no adjustment may be 

made to the system. 

S.3. Design of Discharge Lines and Discharge Line Valves. 

S.3.1. Diversion of Measured Liquid. – No means shall be provided by which any measured liquid can be 

diverted from the measuring chamber of the meter or the discharge line therefrom. However, two or more 

delivery outlets may be permanently installed if means are provided to insure that: 

(a) liquid can flow from only one such outlet at one time, and 

(b) the direction of flow for which the mechanism may be set at any time is definitely and conspicuously 

indicated. 

In addition, a manually controlled outlet that may be opened for the purpose of emptying a portion of the system 

to allow for repair and maintenance operations shall be permitted. Effective means shall be provided to prevent 

the passage of liquid through any such outlet during normal operation of the device and to indicate clearly and 

unmistakably when the valve controls are so set as to permit passage of liquid through such outlet. 

(Amended 1975) 

S.3.2. Delivery Hose. – The delivery hose of a retail device shall be of the wet-hose type with a shutoff valve 

at its outlet end. 

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Handbook 44 – 2010 3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices 

S.4. Marking Requirements. 

S.4.1. Limitation of Use. – If a device is intended to measure accurately only products having particular 

properties, or to measure accurately only under specific installation or operating conditions, or to measure 

accurately only when used in conjunction with specific accessory equipment, these limitations shall be clearly 

and permanently stated on the device. 

S.4.2. Discharge Rates. – A device shall be marked to show its designed maximum and minimum discharge 

rates. The marked minimum discharge rate shall not exceed: 

(a) 20 L (5 gal) per minute for stationary retail devices, or 

(b) 20 % of the marked maximum discharge rate for other retail devices and for wholesale devices. 

(Amended 1987) 

Note: See example in Section 3.30. Liquid-Measuring Devices Code, paragraph S.4.4.1. Discharge Rates. 

(Added 2003) 

S.4.3. Location of Marking Information; Retail Motor-Fuel Dispensers. – The marking information 

required in General Code, paragraph G-S.1. Identification shall appear as follows: 

(a) within 60 cm (24 in) to 150 cm (60 in) from the base of the dispenser; 

(b) either internally and/or externally provided the information is permanent and easily read; and 

(c) on a portion of the device that cannot be readily removed or interchanged (i.e., not on a service access 

panel). 

Note: The use of a dispenser key or tool to access internal marking information is permitted for retail motor-fuel dispensers.

[Nonretroactive as of January 1, 2003] 

(Added 2006) 

S.4.4. Temperature Compensation. – If a device is equipped with an automatic temperature compensator, 

the primary indicating elements, recording elements, and recorded representation shall be clearly and 

conspicuously marked to show that the volume delivered has been adjusted to the volume at 15 °C (60 °F). 

N. Notes 

N.1. Test Liquid. – A device shall be tested with the liquid to be commercially measured or with a liquid of the 

same general physical characteristics. 

N.2. Vaporization and Volume Change. – Care shall be exercised to reduce to a minimum, vaporization and 

volume changes. 

N.3. Test Drafts. – Test drafts should be equal to at least the amount delivered by the device in 1 minute at its 

normal discharge rate. 

(Amended 1982) 

N.4. Testing Procedures. 

N.4.1. Normal Tests. – The “normal” test of a device shall be made at the maximum discharge flow rate 

developed under the conditions of the installation. Any additional tests conducted at flow rates down to and 

including one-half the sum of the maximum discharge flow rate and the rated minimum discharge flow rate 

shall be considered normal tests. 

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3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices Handbook 44 – 2010 

(Amended 1998) 

N.4.1.1. Automatic Temperature Compensation. – On devices equipped with automatic 

temperature-compensating systems, normal tests shall be conducted as follows: 

(a) by comparing the compensated volume indicated or recorded to the actual delivered volume 

adjusted to 15 °C (60 °F); and, 

(b) with the temperature-compensating system deactivated, comparing the uncompensated volume 

indicated or recorded to the actual delivered volume. 

The first test shall be performed with the automatic temperature-compensating system operating in the “as 

found” condition. On devices that indicate or record both the compensated and uncompensated volume for 

each delivery, the tests in (a) and (b) may be performed as a single test. 

(Amended 1987) 

N.4.1.2. Repeatability Tests. – Tests for repeatability should include a minimum of three consecutive 

test drafts of approximately the same size and be conducted under controlled conditions where variations in 

factors such as temperature, pressure, and flow rate are reduced to the extent that they will not affect the 

results obtained. 

(Added 2001) 

N.4.2. Special Tests. – “Special” tests shall be made to develop the operating characteristics of a device and 

any special elements and accessories attached to or associated with the device. Any test except as set forth in 

N.4.1. Normal Tests shall be considered a special test. 

N.4.2.1. For Motor-Fuel Devices. – A motor-fuel device shall be so tested at a minimum discharge rate 

of: 

(a) 20 L (5 gal) per minute, or 

(b) the minimum discharge rate marked on the device, whichever is less. 

N.4.2.2. For Other Retail Devices. – A retail device other than a motor-fuel device shall be tested at a 

minimum discharge rate of: 

(a) the minimum discharge rate that can be developed under the conditions of installation, or 

(b) the minimum discharge rate marked on the device, whichever is greater. 

(Amended 1973) 

N.4.2.3. For Wholesale Devices. – A wholesale device shall be so tested at a minimum discharge rate 

of: 

(a) 40 L (10 gal) per minute for a device with a rated maximum discharge less than 180 L (50 gal) per 

minute. 

(b) 20 % of the marked maximum discharge rate for a device with a rated maximum discharge of 

180 L (50 gal) per minute or more, or 

(c) the minimum discharge rate marked on the device, whichever is least. 

(Amended 1987) 

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Handbook 44 – 2010 3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices 

N.4.3. Money-Value Computation Tests. 

N.4.3.1. Laboratory Design Evaluation Tests. – In the conduct of laboratory design evaluation tests, 

compliance with paragraph S.1.5.2. Money-Value Computations shall be determined by using the cone gear 

as a reference for the total quantity delivered. The indicated delivered quantity shall agree with the cone 

gear representation with the index of the indicator within the width of the graduation. The maximum 

allowable variation of the indicated sales price shall be as shown in Table 1. Money-Value Divisions and 

Maximum Allowable Variations for Money-Value Computations on Mechanical Analog Computers. 

N.4.3.2. Field Tests. – In the conduct of field tests to determine compliance with 

paragraph S.1.5.2. Money-Value Computations the maximum allowable variation in the indicated sales 

price shall be as shown in Table 1. Money-Value Divisions and Maximum Allowable Variations for 

Money-Value Computations on Mechanical Analog Computers. 

(Added 1984) 

N.5. Temperature Correction. – Adjustments shall be made for any changes in volume resulting from the 

differences in liquid temperatures between time of passage through the meter and time of volumetric determination 

in the prover. When adjustments are necessary, appropriate petroleum measurement tables should be used. 

T. Tolerances 

T.1. Application. 

T.1.1. To Underregistration and to Overregistration. – The tolerances hereinafter prescribed shall be 

applied to errors of underregistration and errors of overregistration, whether or not a device is equipped with an 

automatic temperature compensator. 

T.2. Tolerance Values. – The maintenance and acceptance tolerances for normal and special tests shall be as 

shown in Table T.2. Accuracy Classes and Tolerances for LPG and Anhydrous Ammonia Liquid-Measuring 

Devices. 

(Amended 2003) 

Table T.2. 

Accuracy Classes and Tolerances for LPG and Anhydrous Ammonia Liquid-Measuring Devices 

Accuracy 

Class 

Application Acceptance 

Tolerance 

Maintenance 

Tolerance 

Special Test 

Tolerance 

1.0 Anhydrous ammonia, LPG (including 

vehicle-mounted meters) 0.6 % 1.0 % 1.0 % 

(Added 2003) 

T.3. Repeatability. – When multiple tests are conducted at approximately the same flow rate and draft size, the 

range of the test results for the flow rate shall not exceed 40 % of the absolute value of the maintenance tolerance 

and the results of each test shall be within applicable tolerance. This tolerance does not apply to the test of the 

automatic temperature-compensating system. See also N.4.1.2. Repeatability Tests. 

(Added 1992) (Amended 1997 and 2001) 

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3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices Handbook 44 – 2010 

T.4. Automatic Temperature-Compensating Systems. – The difference between the meter error (expressed as a 

percentage) for results determined with and without the automatic temperature-compensating system activated shall 

not exceed: 

(a) 1.0 % for mechanical automatic temperature-compensating systems; and 

(b) 0.5 % for electronic automatic temperature-compensating systems. 

The delivered quantities for each test shall be approximately the same size. The results of each test shall be within 

the applicable acceptance or maintenance tolerance. 

(Added 1991) (Amended 1992, 1996, and 1997) 

UR. User Requirements 

UR.1. Installation Requirements. 

UR.1.1. Discharge Rate. – A device shall be so installed that the actual maximum discharge rate will not 

exceed the rated maximum discharge rate. If necessary, means for flow regulation shall be incorporated in the 

installation, in which case this shall be fully effective and automatic in operation. 

UR.1.2. Length of Discharge Hose. – The length of the discharge hose on a stationary motor-fuel device 

shall not exceed 5.5 m (18 ft), measured from the outside of the housing of the device to the inlet end of the 

discharge nozzle, unless it can be demonstrated that a longer hose is essential to permit deliveries to be made to 

receiving vehicles or vessels. Unnecessarily remote location of a device shall not be accepted as justification 

for an abnormally long hose. 

(Amended 1991) 

UR.2. Use Requirements. 

UR.2.1. Return of Indication and Recording Elements to Zero. – The primary indicating elements 

(visual), and the primary recording elements when these are returnable to zero, shall be returned to zero before 

each delivery. 

UR.2.2. Condition of Fill of Discharge Hose. – The discharge hose shall be completely filled with liquid 

before the “zero” condition is established prior to the start of a commercial delivery, whether this condition is 

established by resetting the primary indicating elements to zero indication or by recording the indications of the 

primary indicating elements. (Also see UR.2.1. Return of Indication and Recording Elements to Zero.) 

UR.2.3. Vapor-Return Line. – During any metered delivery of liquefied petroleum gas from a supplier’s 

tank to a receiving container, there shall be no vapor-return line from the receiving container to the supplier’s 

tank: 

(a) in the case of any receiving container to which normal deliveries can be made without the use of such 

vapor-return line, or 

(b) in the case of any new receiving container when the ambient temperature is below 90 °F. 

UR.2.4. Temperature Compensation. 

UR.2.4.1. Use of Automatic Temperature Compensators. – If a device is equipped with an automatic 

temperature compensator, this shall be connected, operable, and in use at all times. Such automatic 

temperature compensator may not be removed, nor may a compensated device be replaced with an 

uncompensated device, without the written approval of the weights and measures authority having 

jurisdiction over the device. 

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Handbook 44 – 2010 3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices 

UR.2.4.2. Temperature Compensated Sale. – All sales of liquefied petroleum gas in a liquid state, 

when the quantity is determined by an approved measuring system equipped with a temperaturecompensating mechanism, or by weight and converted to liters or gallons, or by a calibrated container, shall 

be in terms of liters or the U.S. gallon of 231 in3

 at 15 °C (60 °F). 

(Added 1984) 

UR.2.4.3. Invoices. – Any invoice based on a reading of a device that is equipped with an automatic 

temperature compensator or based on a weight converted to gallons, or based on the volume of a calibrated 

container, shall have shown thereon that the volume delivered has been adjusted to the volume at 15 °C 

(60 °F). 

(Amended 1984) 

UR.2.4.4. Automated Temperature-Compensating Systems. – Means for determining the temperature 

of measured liquid in an automatic temperature-compensating system shall be so designed and located that, 

in any “usual and customary” use of the system, the resulting indications and/or recorded representations 

are within applicable tolerances. 

(Added 1987) 

UR.2.5. Ticket in Printing Device. – A ticket shall not be inserted into a device equipped with a ticket 

printer until immediately before a delivery is begun, and in no case shall a ticket be in the device when the 

vehicle is in motion while on a public street, highway, or thoroughfare. 

UR.2.6. Ticket Printer; Customer Ticket. – Vehicle-mounted metering systems shall be equipped with a 

ticket printer. The ticket printer shall be used for all sales; a copy of the ticket issued by the device shall be left 

with the customer at the time of delivery or as otherwise specified by the customer. 

(Added 1992) 

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