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Chapter 3. Test Procedures – For Packages Labeled by Volume

3.1. Scope

Use these procedures to determine the net contents of packaged goods labeled in fluid volume such as milk, 

water, beer, oil, paint, distilled spirits, soft drinks, juices, liquid cleaning supplies, or chemicals. This 

chapter also includes procedures for testing the capacities of containers such as paper cups, bowls, glass 

tumblers, and stemware.

These procedures do not cover berry baskets and rigid-dry measures that are covered by specific code 

requirements in NIST Handbook 44 “Specifications, Tolerances, and Other Technical Requirements for 

Weighing and Measuring Devices.” 

If Multiunit or Variety Packages are to be inspected, refer to Chapter 5. “Specialized Test Procedures” for 

guidance in testing. If a total quantity declaration is being verified and the MAV to be applied is not based 

on a percentage of the labeled quantity, refer to Section 1.2.4.1. “Total Quantity MAV for Multiunit and 

Variety Packages.”

(Note Added 2022) 

3.1.1. Test Methods

The gravimetric procedure may be used to verify the net quantity of contents of packages labeled in 

volume when the density (density means the weight of a specific volume of liquid determined at a 

reference temperature) of the product being tested does not vary excessively from one package to 

another. 

If the density varies from one package to another, test each package using the volumetric test procedures 

described in this chapter. Special test methods are required for a number of unique products so care 

should be taken to select the correct test procedure.

Reference Temperature:

In addition to possible package-to-package variations in product density, the temperature of the liquid 

will affect the volume. The product will expand or contract based on a rise or fall in product 

temperature.

Example: 

The volume of a liquid cleaning product might be 5 L (1.32 gal) at 20 °C (68 °F) and 5.12 L 

(1.35 gal) at 25 °C (77 °F), which represents a 2.2 % change in volume. 

Notes: 

(1) This extreme example is for illustrative purposes. A 2.2 % volume change will not occur in 

normal testing.
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Use the reference temperature specified in Table 3-1. “Reference Temperatures for Liquids” to 

determine volume. When checking liquid products labeled by volume using the gravimetric 

procedure, maintain the packages used to determine product densities at reference 

temperatures. If testing the packages in a sample volumetrically, each package in the sample 

must be maintained at or corrected to the reference temperature when its volume is determined.

(2) When checking liquid products using a volumetric or gravimetric procedure, the temperature 

of the samples must be maintained at the reference temperature ± 2 °C (± 5 °F).

Table 3-1. 

Reference Temperatures for Liquids

If the liquid commodity is: Volume is determined at the 

reference temperature of:

Code of Federal Regulation

(CFR) Reference*

Malt (Beer) 4 °C (39.1 °F) 27 CFR 7.10

Distilled Spirits 15.56 °C (60 °F) 27 CFR 5.11

Frozen food - sold and consumed 

in the frozen state At the frozen temperature 21 CFR 101.7(b)(2)(i)

Petroleum 15.6 °C (60 °F) 16 CFR 500.8(b)

Refrigerated food (e.g., milk and 

other dairy products labeled 

“KEEP REFRIGERATED”)

4 °C (40 °F) 21 CFR 101.7(b)(2)(ii)

Other liquids and wine (e.g., 

includes liquids sold in a 

refrigerated state for immediate 

customer consumption such as 

soft-drinks, bottled water and 

others that do not require 

refrigeration)

20 °C (68 °F)

Food: 21 CFR 101.7(b)(2)(iii)

Non-Food: 16 CFR 500.8(b)

Wine: 27 CFR 4.10 (b)

*The Code of Federal Regulations (CFR) can be accessed online at: www.ecfr.gov or 

www.govinfo.gov/app/collection/cfr.

(Amended 2010)

3.2. Gravimetric Test Procedure for Non-Viscous Liquids

3.2.1. Test Equipment

• A scale that meets the requirements in Chapter 2, Section 2.2. “Measurement Standards and 

Test Equipment.”

Note: To verify that the scale has adequate resolution for use, it is first necessary to determine 

the density of the liquid; next verify that the scale division is no larger than MAV/6 for the 

package size under test. The smallest graduation on the scale must not exceed the weight value 

for MAV/6 (see Example for Determining Scale Suitability).
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Example: 

Assume the inspector is using a scale with 1 g (0.002 lb) increments to test packages 

labeled 1 L (33.8 fl oz) that have an MAV of 29 mL (1 fl oz). Also, assume the inspector 

finds that the weight of 1 L of the liquid is 943 g (2.078 lb). This will result in an 

MAV/6 value in weight of 4.557 g (0.010 lb):

Example for Determining Scale Suitability 

(based on the example above)

1. Determine the MAV based on the 

labeled quantity. 

MAV: 29 mL MAV: 1 fl oz

2. Determine the density of the 

liquid. 

Density: 1 Liter = 943 g 

÷ 1000 mL = 0.943 g/mL

Density: 33.8 fl oz = 2.07 

8 lb ÷ 33.8 fl oz = 0.061 

4 lb/fl oz 

3. Convert the MAV from volume to 

weight by multiplying the (volume) 

MAV by the density factor (step 2). 

Divide this result by 6 (MAV/6) and 

compare it to the scale division. 

MAV in Volume 

Converted to Weight 

Divided by 6.

29 mL × 0.943 g/mL ÷ 6

= 4.557 g*

MAV in Volume 

Converted to Weight 

Divided by 6.

1 fl oz × 0.061 4 lb/fl oz

÷ 6 = 0.010 lb 

*In this example, the 1 g (0.002 lb) scale division is smaller than the MAV/6 value of 4.557 g 

(0.010 lb) so the scale is suitable for making a density determination.

• Partial immersion thermometer or equivalent with 1 °C (2 °F) graduations and a − 35 °C to 

+ 50 °C (− 30 °F to + 120 °F) accurate to ± 1 °C (± 2 °F).

• Volumetric measures

Note: When checking packages labeled in SI units, flask sizes of 100 mL, 200 mL, 500 mL, 

1 L, 2 L, 4 L, and 5 L and a 50 mL cylindrical graduate with 1 mL divisions may be used. 

When checking packages labeled in U.S. customary units the use of measuring flasks and 

graduates with capacities of gill, half-pint, pint, quart, half-gallon, gallon, and a 2 fl oz 

cylindrical graduate, graduated to 1

/2 fl dr is recommended.

• Defoaming agents may be necessary for testing liquids such as beer and soft drinks that 

effervesce or are carbonated. Two such products are Hexanol or Octanol (Capryl Alcohol).

• Bubble level at least 152 mm (6 in) in length

• Stopwatch

3.2.2. Test Procedure

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection. Select a random sample.

2. Bring the sample packages and their contents to the reference temperature as specified in 

Table 3-1. “Reference Temperatures for Liquids.” To determine if the liquid is at its reference 

temperature, immerse the thermometer in the liquid before starting the test. Verify the 
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temperature again immediately after the flask and liquid is weighed. If the product requires 

mixing for uniformity, mix it before opening in accordance with any instructions specified on 

the package label. Shaking liquids, such as flavored milk, often entraps air that will affect 

volume measurements, so use caution when testing these products. Often, less air is entrapped 

if the package is gently rolled to mix the contents.

3. For milk, select a volumetric measure equal to or one size smaller than the label declaration. 

For all other products, select a volumetric measure that is one size smaller than the label 

declaration.

(Amended 2004)

Example: 

If testing a 1 L bottle of juice or a soft drink, select a 500 mL volumetric measure.

Note: When determining the density of milk, if the product from the first container does not fill 

the volumetric measure to the nominal capacity graduation, product may be added from another 

container as long as product integrity is maintained (i.e., brand, identity, lot code, and temperature).

4. Prepare a clean volumetric measure to use according to the following procedure:

 Because flasks are ordinarily calibrated on a “to deliver” basis, they must be “wet down” 

before using. Immediately before use, fill the volumetric flask(s) or graduate with water. 

The water should be at the reference temperature of the product being tested. Fill the 

flask(s) with water to a point slightly below the top graduation on the neck. The flask 

should be emptied in 30 seconds (± 5 seconds). Tilt the flask gradually so the flask walls 

are splashed as little as possible as the flask is emptied. When the main flow stops, the 

flask should be nearly inverted. Hold the flask in this position for 10 seconds more and 

touch off the drop of water that adheres to the tip. If necessary, dry the outside of the flask. 

This is called the “wet down” condition. The flask or graduate is then ready to fill with 

liquid from a package. 

Note: When using a volumetric measure that is calibrated “to contain,” the measure must be dry 

before each measurement.

 If the liquid effervesces or foams when opened or poured (such as carbonated beverages), 

add two drops of a defoaming agent to the bottom of the flask before filling with the liquid. 

If working with a carbonated beverage, make all density determinations immediately upon 

placing the product into the standard. This reduces the chance of volume changes occurring 

from the loss of carbonization.

5. If the flask capacity is equal to the labeled volume, pour the liquid into the volumetric measure 

tilting the package to a nearly vertical position. If the flask capacity is smaller than the 

package’s labeled volume, fill the flask to its nominal capacity graduation. 

6. Position the flask on a level surface at eye level. For clear liquids, place a material of some 

dark color outside the flask immediately below the level of the meniscus. Read the volume 

from the lowest point of the meniscus. For opaque liquids, read volume from the center top 

rim of the liquid surface.

7. Evaluate the density variation.
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 Select a volumetric measure equal to or one size smaller than the labeled volume 

(depending on the product) and prepare it as described in Step 4 of this section. Then 

determine and record its empty weight.

 Determine acceptability of the liquid density variation, using two packages as follows:

• Determine the gross weight of the first package.

• Pour the liquid from the first package into a flask. Measure exactly to the nominal 

capacity marked on the neck of the measure.

• Weigh the filled flask and subtract its empty weight to obtain the weight of the liquid. 

Determine density by dividing the weight of the liquid by the capacity of the flask.

• Determine the weight of the liquid from a second package using the same procedure.

• If the difference between the densities of the two packages exceeds one division, use 

the volumetric procedure in Section 3.3. “Volumetric Test Procedure for Non-Viscous 

Liquids.”

8. Determine the Average Used Dry Tare Weight of the sample according to provisions of 

Section 2.3.5. “Procedures for Determining Tare.”

9. Calculate the Average Product Density by adding the densities of the liquid from the two 

packages and dividing the sum by two.

10. Calculate the “nominal gross weight” using the following formula if the flask capacity is equal 

to the labeled volume:

Nominal Gross Weight = (Average Product Density [in weight units]) +

(Average Used Dry Tare Weight)

Note: If the flask size is smaller than the labeled volume, the following formula is used:

Nominal Gross Weight = (Average Product Density ×

[Labeled Volume/Flask Capacity]) + (Average Used Dry Tare Weight)

11. Weigh the remaining packages in the sample.

12. Subtract the nominal gross weight from the gross weight of each package to obtain package 

errors in terms of weight. All sample packages are compared to the nominal gross weight.

13. To convert the average error or package error from weight to volume, use the following 

formula:

Package Error in Volume = Package Error in Weight ÷ Average Product Density Per 

Volume Unit of Measure.
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3.2.3. Evaluation of Results

Follow the procedures in Chapter 2, Section 2.3.7. “Evaluate for Compliance” to determine lot 

conformance.

3.3. Volumetric Test Procedure for Non-Viscous Liquids

If it is determined that the densities of the liquids vary beyond the specified limit, use the volumetric test 

procedure below to test the product.

3.3.1. Test Equipment

• Partial immersion thermometer or equivalent with 1 °C (2 °F) graduations and a − 35 °C to 

+ 50 °C (− 30 °F to + 120 °F) accurate to ± 1 °C (± 2 °F).

• Volumetric measures

Note: When checking packages labeled in SI units, flask sizes of 100 mL, 200 mL, 500 mL, 

1 L, 2 L, 4 L, and 5 L and a 50 mL cylindrical graduate with 1 mL divisions may be used. 

When checking packages labeled in U.S. customary units the use of measuring flasks and 

graduates with capacities of gill, half-pint, pint, quart, half-gallon, gallon, and a 2 fl oz 

cylindrical graduate, graduated to 1

/2 fl dr is recommended.

• Defoaming agents may be necessary for testing liquids such as beer and soft drinks that 

effervesce or are carbonated. Two such products are Hexanol or Octanol (Capryl Alcohol).

• Bubble level at least 152 mm (6 in) in length

• Stopwatch

3.3.2. Test Procedure

1. Follow Steps 1 through 6 in Section 3.2. “Gravimetric Test Procedure for Non-Viscous 

Liquids” for each package in the sample.

2. In Step 5, drain the container into the flask for one minute after the stream of liquid breaks into 

drops.

3. Read the package errors directly from the graduations on the measure. The reference 

temperature must be maintained within ± 2 °C (± 5 °F) for the entire sample.

3.3.3. Evaluation of Results

Follow the procedures in Chapter 2, Section 2.3.7. “Evaluate for Compliance” to determine lot 

conformance.

3.4. Volumetric Test Procedures for Viscous Fluids – Headspace

Depending on how level the surface of the commodity is, use one of the two headspace test procedures. 

Use Section 3.4.2.a. “Test Procedure for Testing Oils, Syrups, and other Viscous Liquids with a Smooth 

and Level Surface” to determine volume where the liquid has a level surface (e.g., oils, syrups, and other 
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viscous liquids). Use Section 3.4.2.b. “Test Procedure for Testing Mayonnaise, Salad Dressing, and Water 

Immiscible Products with no Smooth and Level Surface” to determine volume where the commodity does 

not have a level surface (e.g., mayonnaise and salad dressing).

Before conducting either of the following volumetric test procedures, follow Section 2.3.1. “Define the 

Inspection Lot.” Use a “Category A” sampling plan in the inspection; select a random sample.

(Amended 2019)

3.4.1. Test Equipment

• Micrometer depth gage (ends of rods may be flat or fully rounded) 0 mm to 225 mm (0 in to 

9 in) or longer.

• Level (at least 152 mm [6 in] in length)

• Laboratory pipets and/or buret

 Class A 100 mL buret as defined by the latest version of ASTM E287, “Standard 

Specification for Laboratory Glass Graduated Burets.”

 Class A pipets, calibrated “to deliver “as defined by the latest version of ASTM E969, 

“Standard Specification for Glass Volumetric (Transfer) Pipets.”

• Volumetric measures

• Distilled Water or Reverse Osmosis Water (for use with laboratory pipets and/or burets)

• Water

• Rubber bulb syringe

• Plastic disks that are 3 mm (1/8 in) thick with diameters equal to the seat diameter or larger than 

the brim diameter of each container to be tested. The diameter tolerance for the disks is 50 μm 

(± 0.05 mm [± 0.002 in]). The outer edge should be smooth and beveled at a 30° angle with 

the horizontal to 800 μm (0.8 mm [1/32 in]) thick at the edge. Each disk must have a 20 mm 

(

3

/4 in) diameter hole through its center and a series of 1.5 mm (1/16 in) diameter holes 25 mm 

(1 in) apart around the periphery of the disk and 3 mm (1/8 in) from the outer edge. All edges 

must be smooth.

• Stopwatch

• Partial immersion thermometer (or equivalent) with 1 °C (2 °F) graduations and a range of 

− 35 °C to + 50 °C (− 30 °F to + 120 °F) accurate to ± 1 °C (± 2 °F)

(Amended 2019)
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3.4.2. Test Procedures

Use the volumetric headspace procedure described in this section to determine volume when the 

commodity has a level surface. Open every package in the sample.

1. Bring the temperature of both the liquid and the water to be used to measure the volume of 

the liquid to the reference temperature specified in Table 3-1. “Reference Temperatures for 

Liquids.” Verify with a thermometer that the product has maintained the reference 

temperature.

2. Place the package on a level surface and open it. Measure the headspace of the package at 

the point of contact with the liquid using a depth gage. If necessary, support the package to 

prevent deflection in the bottom of the container that may affect the volume.

3. Empty, clean, and dry the package.

4. Refill the container with water measured from a volumetric standard to the original liquid 

headspace level measured in Step 2 of this procedure until the water touches the depth gage.

5. Determine the amount of water used in Step 4 of this procedure to obtain the volume of the 

liquid and calculate the “package error” based on that volume.

“Package Error” = Labeled Value – Measured Volume

Use the following volumetric headspace procedure to determine volume when the commodity does not 

have a level surface (e.g., mayonnaise, salad dressing, and other water immiscible products without a 

level liquid surface). The procedure guides the inspector to determine the amount of headspace above 

the product in the package and the volume of the container. Determine the product volume by 

subtracting the headspace volume from the container volume. Open and test every package in the 

sample.

(Amended 2010)

Note: Make all measurements on a level surface.

1. Bring the temperature of both the commodity and the water used to measure the volume to 

the appropriate temperature designated in Table 3-1. “Reference Temperatures for Liquids.”

2. Open the first package and place a disk larger than the package container opening over the 

opening.

3. Measurement Procedure:

 Deliver water from a flask (or flasks), graduate, or buret, through the central hole in the 

disk onto the top of the product until the container is filled. If it appears that the contents 

of the flask may overfill the container, do not empty the flask. Add water until all of the 
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air in the container has been displaced and the water begins to rise in the center hole of 

the disk. Stop the filling procedure when the water fills the center disk hole and domes 

up slightly due to the surface tension. Do not add additional water after the level of the 

water dome has dropped.

 If the water dome breaks on the surface of the disk, the container has been overfilled and 

the test is void; dry the container and start over.

4. To obtain the headspace capacity, record the volume of water used to fill the container and 

subtract 1 mL (0.03 fl oz), which is the amount of water held in the hole in the disk specified.

5. Empty, clean, and dry the package container.

6. Using Steps 3 and 4 of this procedure, refill the package container with water measured from 

a volumetric measure to the maximum capacity of the package, subtract 1 mL (0.03 fl oz), 

and record the amount of water used as the container volume; and

7. From the container volume determined in Step 6 of this procedure, subtract the headspace 

capacity in Step 4 of this procedure to obtain the measured volume of the product.

8. Calculate the “package error” for that volume where “package error” equals labeled volume 

minus the measured volume of the product.

3.4.3. Evaluation of Results

For either of the above procedures, follow the procedures in Section 2.3.7. “Evaluate for Compliance”

to determine lot conformance.

3.5. Goods Labeled by Capacity – Volumetric Test Procedure

3.5.1. Test Equipment

Use the test equipment in Section 3.4. “Volumetric Test Procedures for Viscous Fluids – Headspace” 

(except for the micrometer depth gage) to perform this test procedure.

3.5.2. Test Procedure

Note: Make all measurements on a level surface.

1. Before conducting any of the following volumetric test procedures, refer to 

Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection; select a random sample.

2. When testing goods labeled by capacity, use water at a reference temperature of 20 °C ± 2 °C 

(68 °F ± 5 °F).

3. Select a sample container and place a disk larger than the container opening over the opening.

4. Measurement Procedure:
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 Add water to the container using flask (or flasks), graduate, or buret corresponding to 

labeled capacity of the container. If it appears that the contents of the flask may overfill 

the container, do not empty the flask. Add water until all of the air in the container has 

been displaced and the water begins to rise in the center hole of the disk. Stop filling the 

container when the water fills the center disk hole and domes up slightly due to the surface 

tension.

 If the water dome breaks on the surface of the disk, the container has been overfilled and 

the test is void; dry the container and start over.

 Record the amount of water used to fill the container and subtract 1 mL (0.03 fl oz) this is the 

amount of water held in the hole in the disk specified) to obtain the total container volume.

5. Test the other containers in the sample according to Steps 3 and 4 of this procedure.

6. To determine package errors, subtract the total container volume obtained in Step 4 of this 

procedure from the labeled capacity of the container.

3.5.3. Evaluation of Results

Follow the procedures in Section 2.3.7. “Evaluate for Compliance” to determine lot compliance.

3.6. Pressed and Blown Glass Tumblers and Stemware

This handbook provides a tolerance to the labeled capacity of glass tumblers and stemware. The average 

requirement does not apply to these products. (see Table 3-2. “Allowable Differences for Pressed and 

Blown Glass Tumblers and Stemware.”)

3.6.1. Test Equipment

Use the test equipment in Section 3.4. “Volumetric Test Procedures for Viscous Fluids – Headspace” 

(except for the micrometer depth gage) to perform this test procedure.

3.6.2. Test Procedure

1. Follow Section 2.3.1. “Define the Inspection Lot” and determine which sampling plan to use 

in the inspection, select a random sample, and then use the volumetric test procedure in Section 

3.5. “Goods Labeled by Capacity – Volumetric Test Procedure” to determine container 

capacity and volume errors.

2. Compare the individual container error with the allowable difference that applies in Table 3-2. 

“Allowable Differences for Pressed and Blown Glass Tumblers and Stemware.” If a package 

contains more than one container, all of the containers in the package must meet the allowable 

difference requirements in order for the package to pass.
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Table 3-2. 

Allowable Differences for Pressed and Blown Glass Tumblers and Stemware

Unit of Measure

If the capacity in metric units is: The allowable difference is:

200 mL or less ± 10 mL

More than 200 mL ± 5 % of the labeled capacity 

If the capacity in U.S. customary units is: Then the allowable difference is:

5 fl oz or less ± 1/4 fl oz

More than 5 fl oz ± 5 % of the labeled capacity

3.6.3. Evaluation of Results

Count the packages in the sample with volume errors greater than the allowable difference and compare 

the resulting number with the number given in Column 3. (Appendix A, Table 2-11. “Sampling Plans 

and Accuracy Requirements for Packages Labeled by Low Count [50 or Fewer] and Packages Given 

Tolerances [Glass and Stemware]) 

• If the number of containers in the sample with errors exceeding the allowable difference 

exceeds the number allowed in Column 3, the lot fails.

• If the number of packages with errors exceeding the allowable difference is less than or equal 

to the number in Column 3, the lot passes.

Note: The average capacity error is not calculated because the lot passes or fails based on the individual 

volume errors. Take action on the individual units containing errors exceeding the allowable difference.

3.7. Volumetric Test Procedure for Paint, Varnish, and Lacquers – Non-Aerosol 

The following procedure is used to verify the net quantity of contents of containers of paint, varnish, wood 

stains, sealants, lacquers or like products labeled by volume. For the purposes of this test procedure the 

term “paint” includes any liquid or product (i.e., varnish lacquers, and other coatings). 

(Amended 2019) 

3.7.1. Test Equipment

• A scale that meets the requirements in Section 2.2. “Measurement Standards and Test 

Equipment” 

• Volumetric measures

• Partial immersion thermometer (or equivalent with 1 °C (2 °F) graduations and a range of – 35 °C 

to + 50 °C (– 30 °F to + 120 °F) accurate to ± 1 °C (± 2 °F) 

• Micrometer depth gage (ends of rods may be flat or fully rounded), 0 mm to 225 mm (0 in to 9 in) 

• Spanning bar, 25.4 mm × 25.4 mm × 304 mm or (1 in × 1 in × 12 in) 
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• Ruler, 304 mm (12 in)

• Paint solvent or other solvent suitable for the product being tested

• Cloth, 304 mm (12 in) square

• Wood, 50 mm (2 in) thick × 150 mm (6 in) wide × 300 mm (12 in) long

• Rubber mallet

• Metal disk or other appropriate shape, 6.4 mm (1⁄4 in) thick and slightly smaller than the 

diameter of package container bottom

• Rubber spatula

• Level at least 152 mm (6 in) in length

• Distilled water or reverse osmosis water

• Micrometer (optional)

• Stopwatch

(Amended 2019)

3.7.2. Test Procedures

Use the following procedure to conduct an audit inspection in a production facility. This method applies 

to containers in a sample that are the lightest in weight and likely to contain the smallest volume of 

product. Duplicate the level of fill with water in an empty unused container of the same dimensions 

and capacity as the one under test. Use this method to check any size rigid container, if the liquid level 

is within the measuring range of the depth gage. If any paint is clinging to the sidewall or lid, carefully 

scrape the paint into the container using a rubber spatula to ensure the full content volume is measured.

Note: Do not shake or invert the containers selected as the sample.

1. Follow Section 2.3.1. “Define the Inspection Lot” to determine which “Category A” sampling 

plan to use; select a random sample. 

Note: The sample containers shall be identically labeled as to volume, brand, commodity, color, 

and lot.

2. Determine the gross weight of the sample container. Record the gross weight of the lightest 

and heaviest container.

3. Select the lightest container and place it on a level work surface and open it. Place a spanning 

bar and depth gage across the top center of the container. Lower the depth gage rod until its 

point touches the surface of the paint and lock the rod adjustment. 
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4. Obtain an empty, unused – undamaged container of the same type and capacity as the 

container under test from the packer. Place the container on a rigid level work surface and 

place a disk or other appropriate support under the bottom to prevent deflection.

5. Use a volumetric flask or cylinder to fill the container with water [water reference temperature 

20 °C ± 2 °C (68 °F ± 5 °F)] to the largest labeled quantity declared on the container.

6. Place the spanning bar and depth gage (locked at the surface depth of the paint in the container 

measured in Step 3.) across the top center of the container. If the point of the depth gage is at 

or below the surface of the water added in Step 4. assume the container is not short measure. 

When the audit test indicates that a short measure may exist in the sample container, then use 

Section 3.7.2.b. “Compliance Test Procedure”.

(Added 2019)

Use the following procedure when testing rigid containers of paint when they have failed the plant audit 

test. This procedure is used to test paint or other liquid whether testing is performed inside the plant or 

at retail.

Note: Do not shake or invert the containers selected as the sample.

1. Follow Section 2.3.1. “Define the Inspection Lot” to determine which “Category A” sampling 

plan to use; select a random sample. 

Note: The sample containers shall be identically labeled as to the volume, brand, commodity, 

color, and lot. The steps noted with an (*) are required if there is paint adhering to the lid and it 

cannot be removed by scraping into the container.

2. Determine the gross weight of these containers and record in Column 2 of the “Example 

Worksheet for Determing Possible Violation in Checking Paint” (in this section). Select and 

test the containers in order of the lightest to the heaviest.

3. Record the labeled volume of the first tare sample package in Column 1 of the worksheet. 

Place the container on a level surface and use a circular (or appropriately shaped) metal or 

other solid disk to eliminate deflection in the bottom of the container and remove the lid. If 

paint clings to the lid of the container, scrape it off with a spatula and place back into the 

container.

4. *If paint that adheres to the lid cannot be completely removed then by scraping the paint into 

the container, determine the weight of the lid plus any adhering paint. Clean (dry) the paint 

lid with solvent and weigh again. Subtract the clean (dry) lid weight from the lid weight with 

paint (wet) to determine the weight of the paint adhering to the lid. Record this weight in

Column 3.

5. Place the spanning bar and depth gage across the top center of the container. Mark the location 

of the spanning bar on the rim of the container. Lower the depth gage rod until the point 

touches the paint surface and lock the rod adjustment.

6. Empty and clean the sample container and lid with solvent; dry and weigh the container and 

lid. Record the tare weight in Column 5.
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7. Set up the container in the same manner as in Step 3.

8. Place the spanning bar at the same location on the rim of the paint container as marked in 

Step 5. With the depth gage set as described in Step 5, deliver water into the container in 

known amounts until the water reaches the same level occupied by the paint as indicated by 

the depth gage. Record this volume of water (in mL or fl oz) in Column 6 of the worksheet. 

This is the volume occupied by the paint in the container. Follow Steps 9a, 10a, and 11a if 

scraping does not remove the paint from the lid. To determine if gravimetric testing can be 

used to test the other containers in the sample, follow only Steps 9, 10, and 11 when no paint 

adheres to the lid.

9. Subtract the weight of the container (Column 5) from the gross weight (Column 2) to arrive 

at the net weight of paint in the selected container. Record the net weight in Column 7 of the 

worksheet.

9a.* Subtract the weight of the container (Column 5) and the weight of product on the lid 

(Column 3) from the gross weight (Column 2) to arrive at the net weight of paint in 

the container. Record in Column 7 (excluding the weight of the paint on the lid).

10. Calculate the weight of the labeled volume of paint (for the first container opened for tare).

net weight (Column 7) × labeled volume (Column 1) ÷ volume of paint in can (Column 6)

Record this value in Column 8.

10a.* Calculate the package volume = 

volume in container (Column 6) + (lid weight [Column 3] ×

volume in container [Column 6] ÷ net weight [Column 7])

Record it in Column 9 of the worksheet.

11. Calculate the package error. Use the following formula if paint does not adhere to the lid.

Package error = (Column 6 value) − (labeled volume)

11a.* Use the following formula if paint does adhere to the lid and will not come off by 

scraping.

Package error = (Column 9 value) − (labeled volume)

12. Repeat Steps 2 through 11 for the second package chosen or tare

(Amended 2010 and 2019)
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Example Worksheet for Determining Possible Violation in Checking Paint

(add additional rows as needed)

1.

Labeled 

Volume

2.

Gross 

Weight

3.

Lid Weight

(Wet − Dry)

4. 

Liquid 

Level

5.

Tare

6.

Water 

Volume

7.

Net Wt. = 

2 − 5

8.

Weight of 

Labeled 

Volume = 

7 × 1 ÷ 6

9.

Package 

Volume =

6+[(3 ÷7)×6)]

Note: A gravimetric procedure can be used if the weights of the labeled volume for the first two 

containers do not differ from each other by more than one division on the scale (if they meet this 

criterion, check the rest of the sample gravimetrically and record in Column 8). The weight of a 

given volume of paint often varies considerably from container to container; therefore, 

volumetric measurement may prove necessary for the entire sample using the headspace 

procedure in Step 8. To determine the volume and enter the Package Volume in Column 9. 

Proceed to procedures in Section 2.3.7. “Evaluate for Compliance”.

Note: To conserve inspection time and reduce destructive testing the inspector may stop testing 

and consider this test as an audit if the first few containers contain the correct. However, the 

inspector may continue to test the complete sample to determine the average fill level of the entire 

sample.

13. Use Section 2.3.6. “Determine Nominal Gross Weight and Package Error” to determine the 

“Nominal Gross Weight” as follows:

The nominal gross weight equals the sum of the average weight of the labeled volume 

(average of values recorded in Column 8) plus the average tare (average of values recorded 

in Column 3) for the containers selected for tare. 

3.7.3. Evaluation of Results

Follow the procedures in Section 2.3.7. “Evaluate for Compliance” to determine lot conformance.

(Amended 2019)

3.8. Testing Viscous Materials – Such As Caulking Compounds and Pastes

Use the following procedure for any package of viscous material labeled by volume. It is suitable for very 

viscous materials such as cartridge-packed caulking compounds, glues, pastes, and other similar products. 

It is best to conduct this procedure in a laboratory using a hood to ventilate solvent fumes. If used in the 

field, perform the test in a well-ventilated area. Except for the special measurement procedures to determine 

the weight of the labeled volume, this procedure follows the basic test procedure.

3.8.1. Test Equipment

• A scale that meets the requirements in Section 2.2. “Measurement Standards and Test 

Equipment.”
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• Pycnometer (pik·nämˊ ət ər), a vessel of known volume used for weighing semifluids. The 

pycnometer can be bought or made. If it is made, refer to it as a “density cup.” To make a 

150 mL or 5 fl oz density cup, cut off the lip of a 150 mL beaker with an abrasive saw and 

grind the lip flat on a lap wheel. The slicker plate is available commercially. The metrology 

laboratory should calibrate the density cup gravimetrically with respect to the contained volume 

using the procedure as defined by the latest version of ASTM E542, “Standard Practice for 

Calibration of Laboratory Volumetric Apparatus.”

Note: If applicable, comply with any special instructions furnished by the manufacturer to calibrate a 

pycnometer that has not been calibrated. It is not necessary to reweigh or recalibrate for each test; 

however, mark the pieces of each unit to prevent interchange of cups and slicker plates.

• Appropriate solvents (water, Stoddard solvent, kerosene, alcohol, etc.)

• Caulking gun (for cartridge packed products)

3.8.2. Test Procedure

1. Follow the procedures in Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” 

sampling plan in the inspection; and select a random sample.

2. Weigh a calibrated pycnometer and slicker plate and record as “pycnometer weight” and record 

the volume of the pycnometer.

3. Determine the gross weight of the first package and record the weight value. Open the package 

and transfer the product to the pycnometer by filling it to excess. Use a caulking gun to transfer 

product from the caulking cartridges. If using a pycnometer, cover it with a lid and screw the 

cap down tightly. Excess material will be forced out through the hole in the lid, so the lid must 

be clean. If using a density cup, place the slicker plate over 3⁄4 of the cup mouth, press down 

and slowly move the plate across the remainder of the opening. With the slicker plate in place, 

clean all the exterior surfaces with solvent and dry.

4. Completely remove the product from the package container; clean the package container with 

solvent; dry and weigh it to determine the tare weight.

5. Weigh the filled pycnometer or filled density cup with slicker plate and record this weight. 

Subtract the weight of the empty pycnometer from the filled weight to determine the net weight 

of the product contained in the pycnometer and record this weight.

6. Clean the pycnometer and repeat Steps 3, 4, and 5 for the second package in the tare sample.

7. Determine acceptability of the density variation on the two packages selected for tare. If the 

difference between the densities of the two packages exceeds one division of the scale, do not 

use the gravimetric procedure to determine the net quantity of contents. Instead, use the 

procedure in steps 9, 10, and 11.

Weight of Product in Pycnometer ÷ Pycnometer Volume = Product Density

Note: If the gravimetric procedure can be used, perform Steps 8, 10, and 11 for each package in 

the sample.
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8. Calculate the weight of product corresponding to the labeled volume of product according to 

the following formula:

Product Density × Labeled Volume = Labeled Weight

9. Test each package individually by determining the product density in each package using the 

pycnometer and record the gross, tare, and net weight of each package. Subtract the weight of 

the labeled volume (determined for each package) from the net weight of product to arrive at 

each individual package error in units of weight.

10. Convert the package errors to units of volume using the following formula:

Package Error (volume) =

(Package Error [weight] × Pycnometer Volume) ÷ (Weight of Product in Pycnometer)

11. Record the package errors on the report form, using an appropriate unit of measure.

3.8.3. Evaluation of Results

Follow the procedures in Section 2.3.7. “Evaluate for Compliance” to determine lot conformance.

3.9. Peat Moss

3.9.1. Dimensional Test Procedure for Compressed Quantity

(Added 2015)

3.9.1.1. Test Equipment

• Calculator or spreadsheet Software (programmed to make volume calculations

• Worksheet for Peat Moss Labeled by Volume – Dimensional Procedure (see Appendix C. 

“Model Inspection Report Forms.”)

• Non-permanent marking pen.

• Knife or razor cutter (for use in opening packages and unwrapping shrink-wrapped pallets 

in warehouses)

• Cellophane or duct tape (for use in securing packaging tails)

• Dimensional Measuring Frame (see Figure 3-1. “Dimensional Measuring Frame”).
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• Rigid Rulers – Starrett or equal with 1.0 mm graduations. The edges of a ruler used with 

a measuring frame must be straight and the edges must be the zero point (see 

Figure 3-1. “Dimensional Measuring Frame”).

 304 mm (12 in)

 500 mm (19.5 in)

 1 m (39 in)

• Carpenter square

 304 mm (12 in)

 600 mm (24 in)

(Amended 2015)

3.9.1.2. Test Procedure

Test Notes:

Rounding: When a package measurement falls between graduations on a ruler, round the 

value up. This practice eliminates the issue of rounding from the volume determination and 

provides the packager the benefit of the doubt. If a ruler with a graduation of 1.0 mm is used, 

the rounding error will be limited to 0.5 mm or less. It is good practice to circle a measurement 

that has been rounded up or make a statement to such effect so that it becomes a part of the 

record.

Dimension Identification: The following package nomenclature is used to identify the 

dimensions measured in this test procedure (see Figure 3-2. “Dimensional Identification”).

Figure 3-1. Dimensional Measuring 

Frame
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Note: Packages of compressed peat moss do not have 

declaration of expanded volume.

Safety Precautions:

This procedure does not address all of the safety issues that users need to be aware of in order to 

carry out the following tasks. Users are sometimes required to conduct tests in warehouse spaces 

or retail stores where forklift trucks are in motion – care must be taken to warn others to avoid or 

exercise care around the test site. The procedure requires users to lift heavy objects including large 

bulky packages and test measures and includes the use of sharp instruments to obtain packages 

from shrink-wrapped pallets. Users may be required to climb ladders or work platforms to obtain 

sample packages. When opening and emptying packages, dust, or other particles may be present 

or escape from the packages, which may cause eye injuries and respiratory or other health problems. 

Users must utilize appropriate safety equipment and exercise good safety practices. If safe working 

conditions cannot be ensured, suspend testing until the situation is corrected. 

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” Sampling Plan for 

the inspection. Collect the sample packages from the Inspection Lot using random 

sampling. If the packages are not randomly selected, the sample will not be representative 

of the lot and the test results will not be valid for use in enforcement action. Place the 

sample packages in a location where there is adequate lighting and ample space for the 

packages and test equipment. 

2. Examine the package for excess packaging material (i.e., packaging tails). Fold the 

packaging material consistent with design of the packaging and tape the material securely 

to the package so that its effect on the dimensional measurement is minimized. If the 

thickness of packaging tail appears excessive, it is appropriate to determine its average 

thickness by making at least three measurements along its length using a dead weight dial 

micrometer specified in Section 4.5. “Polyethylene Sheeting” and subtract the thickness 

from the measurement of length, width or height. Any deduction from a measurement 

should be noted on the inspection report. 

3. If a Dimensional Measuring Frame is used, place it on a solid support. If a table is used, 

select one of sufficient load capacity to hold the weight of the frame and the heaviest 

package to be tested. 

Figure 3-2. Dimensional Identification
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4. Position the frame so that the zero end of the ruler can be placed squarely and firmly against 

a surface of the frame and so that the ruler graduations can be read. Position yourself so 

that you can read both the ruler and the edge of the carpenter square in Figure 3-3. “Rigid 

Frame.”

5. Place the package against two sides of the frame without compressing the package. Place 

a carpenter square against the package at the point of measurement and align the ruler 

perpendicular to the edge of the carpenter square as shown in Figure 3-4. “Length 

Measurement” where the package length and Figure 3-5. “Height Measurement” where the 

package height are being determined. 

6. Measurements – take at least five measurements* of each of the dimensions as follows:

*On small packages (height or length dimensions of 152 mm [6 in] or less), at least three 

measurements are taken using the following instructions.

Figure 3-3. Rigid Frame. The rigid frame 

allows the observer to hold the zero reference 

point firmly in place.

Figure 3-4. Length Measurement.

Using a Measuring Frame for 

Dimensional Testing Ruler and 

Carpenter Square Define Zero 

Reference and Measurement Point.
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Inspect the package for shape and place the flattest surfaces against the measuring frame.

Length (see Figure 3-4. “Length Measurement”)

(a) Take the first measurement across the center line of the 

length axis of package.

(b) Take the second measurement at half the distance 

between the center line and either of the package edges.

(c) Take the third measurement half the distance between the 

second measurement and the package edge.

(d) Take the fourth measurement on the opposite end of the 

package at half of the distance between the center line 

and the package edge.

(e) Take the fifth measurement at half of the distance 

between the fourth measurement and the package edge.

Height (see Figure 3-5. “Height Measurement”):

(a) Take the first measurement across the center line of the 

height axis of the package.

(b) Take the second measurement at half the distance 

between the center line and the package edge.

(c) Take the third measurement half the distance between the 

second measurement and the package edge.

(d) Take the fourth measurement on the opposite end of the 

package at half of the distance between the center line and 

the package edge.

(e) Take the fifth measurement at half of the distance 

between the fourth measurement and the package edge.

Width (see Figure 3-6. “Width Measurement”): If using one, 

turn the measuring frame on end and place the package on its 

bottom and against the frame as shown in the picture and on 

the right where the package width is being measured. 

(a) Take the first measurement across the center line of width 

axis of the package.

(b) Take the second measurement at half the distance 

between the center line and the package edge.

(c) Take the third measurement half the distance between the 

second measurement and the package edge.

(d) Take the fourth measurement on the opposite end of the 

package at half the distance between the center line and 

the package edge.

(e) Take the fifth measurement half of the distance between 

the forth measurement and the package edge.

Center

Second

Third

Fourth

Fifth

Length 

Center Line

Height

Width

Center 

Line
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7. Record the dimensions of each package in millimeters in a software program or inspection 

form that includes the information shown in the sample worksheet “Calculate the 

Compressed Volume of the Package in Liters” (below). Enter the measurements in the 

appropriate spaces and calculate the volume in liters. Calculate the package error by 

following the steps listed in the table and then calculate the average error for the sample. 

Note: The following table is an example of the information from an actual test that is included 

in a worksheet for verifying the compressed volume on packages of peat moss. The Peat Moss 

Labeled by Volume Package Worksheet – Dimensional Procedure (see Appendix C. Model 

Inspection Forms) has space for a sample of 12 packages and includes the steps for calculating 

the Average Package Error. Here, the package error in the dimensional volume was + 6.8 L 

(+ 0.24 ft3

). To determine the value of the MAV, look up the labeled quantity in Appendix A., 

Table 2-6. “Maximum Allowable Variations for Packages Labeled by Liquid and Dry 

Volume.” 

Sample Worksheet

Calculate the Compressed Volume of the Package in Liters

Unit of Measure = 1.0 mm Length (L) Width (W) Height (H)

1. 482 282 690

2. 490 278 690

3. (Center Line) 493 276 681

4. 499 272 677

5. 493 269 657

a. Average: 491 275.4 679

b. L × W × H = Volume/1 000 000 91.8L 

c. Labeled Compressed Quantities: 85.0 L NA cu in 3.0 cu ft

Figure 3-5. Height Measurement. The 

packaging tail on the end of the package 

can affect this measurement so it has been 

folded over and taped against the end of the 

package.

Figure 3-6. Width Measurement. 

The frame is rotated on its end to 

vertical so that the carpenter square 

does not compress the product.
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Sample Worksheet

Calculate the Compressed Volume of the Package in Liters

Unit of Measure = 1.0 mm Length (L) Width (W) Height (H)

d. Conversion Factors NA (b) × 61.02374 (b) × 0.03531467

e. Converted Volume 85.0 L NA cu in 3.24 cu ft

f. Package Error = (b – c) 6.8 L NA cu in 0.24 cu ft

(Amended 2010 and 2015)

3.9.2. Uncompressed Volume Packages

Use the following method to test peat moss sold using an uncompressed volume as the declaration of 

content. The procedure as defined by the latest version of ASTM D2978, “Standard Test Method for 

Volume of Processed Peat Materials.”

3.9.2.1. Test Equipment

• 12.7 mm (or 1

/2 in) sieve

• Use a measure appropriate for the package size. (Refer to Table 3-4. “Specifications for 

Test Measures for Mulch and Soils” for additional information on test measure size and 

construction.)

• Straight edge, 508 mm (20 in) in length

• Sheet for catching overflow of material

• Level (at least 152 mm [6 in] in length)

(Amended 2015)

3.9.2.2. Test Procedure

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in 

the inspection; select a random sample.

2. Open each package and pour the contents from a height of 2 ft through the sieve directly 

into the measuring container (overfilling it). Use this method for particulate solids (such 

as soils or other garden materials) labeled in cubic dimensions or dry volume. Some 

materials may not pass through the sieve for peat moss; in these instances, separate the 

materials by hand (to compensate for packing and settling of the product after packaging) 

before filling the measure.

Note: Separated material (product not passing through the sieve) must be included in the 

product volume.

3. Shake the measuring container with a rotary motion at one rotation per second for five 

seconds. Do not lift the measuring container when rotating it. If the package contents are 

greater than the measuring container capacity, level the measuring container contents with 

a straightedge using a zigzag motion across the top of the container.
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4. Empty the container. Repeat the filling operations as many times as necessary, noting the 

partial fill of the container for the last quantity delivered using the interior horizontal 

markings as a guide.

5. Record the total volume.

6. To compute each package error, subtract the labeled quantity from the total volume and 

record it.

(Amended 2015)

3.9.3. Evaluation of Results

Follow the procedures in Section 2.3.7. “Evaluate for Compliance” to determine lot conformance for 

either procedure.

(Amended 2015)

3.10. Mulch and Soils Labeled by Volume

Mulch is defined as “any product or material except peat or peat moss that is advertised, offered for sale, 

or sold for primary use as a horticultural, above-ground dressing, for decoration, moisture control, weed 

control, erosion control, temperature control, or other similar purposes.”

Soil is defined as “any product or material, except peat or peat moss that is advertised or offered for sale, 

or sold for primary use as a horticultural growing media, soil amendment, and/or soil replacement.”

3.10.1. Test Equipment

• A test measure appropriate for the package size that meets the specifications for test measures 

in Table 3-4. “Specifications for Test Measures for Mulch and Soils”

• Drop cloth/polyethylene sheeting for catching overflow of material

• Level (at least 152 mm [6 in] in length)
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Table 3-4. 

Specifications for Test Measures for Mulch and Soils

Nominal

Capacity of 

Test Measure4

Actual

Volume of 

the 

Measure4

Interior

Length1

Interior

Width1

Interior

Height2

Marked 

Intervals 

on Interior

Wall3

Volume 

Equivalent

of Marked 

Intervals

30.2 L

(1.07 cu ft)

for testing 

packages that 

contain less than 

28.3 L

(1 cu ft or

25.7 dry qt)

31.9 L

(1.13 cu ft)

213.4 mm

(8.4 in)

203.2 mm

(8 in)

736.6 mm

(29 in)

12.7 mm

(

1

/2 in)

550.6 mL

(33.6 in3)

28.3 L

(1 cu ft)

33.04 L

(1.16 cu ft)

304.8 mm

(12 in)

304.8 mm

(12 in) 355.6 mm

(14 in)

1179.8 mL

(72 cu in)

406.4 mm

(16 in)

228.6 mm

(9 in)

56.6 L

(2 cu ft)

63.7 L

(2.25 cu ft)

304.8 mm

(12 in)

304.8 mm

(12 in)

685.8 mm

(27 in)

406.4 mm

(16 in)

228.6 mm

(9 in)

685.8 mm

(27 in)

84.9 L

(3 cu ft)

92 L

(3.25 cu ft)

304.8 mm

(12 in)

304.8 mm

(12 in)

990.6 mm

(39 in)

406.4 mm

(16 in)

228.6 mm

(9 in)

990.6 mm

(39 in)

Measures are typically constructed of 1.27 cm (1/2 in) marine plywood. The measure must accommodate the entire 

contents of the package being tested, and a transparent sidewall is useful for determining the level of fill, but must 

be reinforced if it is not thick enough to resist distortion. If the measure has a clear front, place the level gage at 

the back (inside) of the measure so that the markings are read over the top of the mulch. 

Notes

1

Other interior dimensions are acceptable if the test measure approximates the configuration of the package under 

test, can accommodate the entire contents of the package at one time and does not exceed a base configuration of 

the package cross-section. 

2

The height of the test measure shall be 355.6 mm (14 in) for a 1 cu ft package, 685.8 mm (27 in) for a 1.5 cu ft to 

2 cu ft package or 990.6 mm (39 in) for a 3 cu ft package.

3

When lines are marked in boxes, they should extend to all four sides of the measure, if possible to improve 

readability. It is recommended that a line indicating the MAV level also be marked to reduce the possibility of 

reading errors when the level of the mulch is at or near the MAV.

4

The Nominal Capacity is given to identify the size of packages that can be tested in a single measurement using 

the dry measure with the listed dimensions. It is based on the most common package sizes of mulch in the 

marketplace. If the measures are built to the dimensions shown above the actual volume will be larger than the 

nominal volume so that plus errors (overfill) can be measured accurately. 

(Amended 2010 and 2017)
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3.10.2. Test Procedure 

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection, and select a random sample.

2. Some types of mulch are susceptible to clumping and compacting. To ensure that the material 

is loose and free flowing when placed into the test measure, gently massage the package while 

rolling the bag on the ground (or flat surface) at least four full rotations (but not more than eight 

full rotations), without lifting or dropping the package, before opening to reduce the clumping 

and compaction of the material.

Note: Mulch products stored exposed to the elements may become saturated with moisture. 

Excessive moisture adds weight to mulch particles and distorts the volume test results. Test 

samples with flowing or excessive collected moisture in the package shall be excluded from the 

test procedure.

3. Placing contents into the test measure. 

 Open the bag, gather the bag opening to ensure that no product is lost. Place the gathered 

bag opening as far into the top of the measure as possible without disturbing or leaning 

against the measure.

 Release the bag opening and quickly dump the contents of the package into a test measure 

in a continuous flow.

Note: Do not touch the product or disturb the test measure by rocking, shaking, dropping or 

tamping it during the test procedure.

 Massage the outside of the bag to maintain a continuous flow of the product but not for the 

purpose of de-clumping the product. 

 Using your hand, gently level the contents, being careful not to affect the compaction of 

the product.

4. Read the horizontal marks at a position level with the product and round the readings between 

two marked intervals up to the nearest 38.1 mm (1/2 in) increment to determine the package net 

volume.

5. Determine package errors by subtracting the labeled volume from the package net volume in 

the measure. Record each package error.

Package Error = Package Net Volume − Labeled Volume

(Amended 2017)

3.10.3. Evaluation of Results

Follow the procedures in Section 2.3.7. “Evaluate for Compliance” to determine lot conformance.

Note: In accordance with Appendix A, Table 2-10. “Exceptions to the Maximum Allowable Variations

for Textiles, Polyethylene Sheeting and Film, Mulch and Soil Labeled by Volume, Packaged Firewood

and Stove Wood Labeled by Volume, and Packages Labeled by Count with 50 Items or Fewer, and 
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Specific Agricultural Seeds Labeled by Count”, apply an MAV of 5 % of the declared quantity to mulch 

and soil sold by volume. When testing mulch and soil with a net quantity in terms of volume, one 

package out of every 12 in the sample may exceed the 5 % MAV (e.g., one in a sample of 12 packages; 

two in a sample of 24 packages; four in a sample of 48 packages). However, the sample must meet the 

average requirement of the “Category A” Sampling Plan. 

3.11. Ice Cream Novelties

Note: The following procedure can be used to test packaged products that are solid or semisolid and that 

will not dissolve in, mix with, absorb, or be absorbed by the fluid into which the product will be immersed. 

For example, ice cream labeled by volume can be tested using ice water or kerosene as the immersion fluid.

Exception: Pelletized ice cream is beads of ice cream which are quick frozen with liquid nitrogen. The 

beads are relatively small, but can vary in shape and size. On April 17, 2009, the FDA issued a letter stating 

that this product is considered semisolid food, in accordance with 21 CFR 101.105(a). The FDA also 

addresses that the appropriate net quantity of content declaration for pelletized ice cream products be in 

terms of net weight.

(Added 2010)

The following volume displacement procedure uses a displacement vessel specifically designed for ice 

cream novelties such as ice cream bars, ice cream sandwiches, or cones. The procedure determines the 

volume of the novelty by measuring the amount of water displaced when the novelty is submerged in the 

vessel. Two displacements per sample are required to subtract the volume of sticks or cups.

The procedure first determines if the densities of the novelties are the same from package to package (in 

the same lot) so that a gravimetric test can be used to verify the labeled volume. If a gravimetric procedure 

is used, compute an average weight for the declared volume from the first two packages and weigh the 

remainder of the sample. If the gravimetric procedure cannot be used, use the volume displacement 

procedure for all of the packages in the sample. 

3.11.1. Test Equipment

• A scale that meets the requirements in Section 2.2. “Measurement Standards and Test 

Equipment” 

• Volumetric measures

• Displacement vessel with dimensions appropriate for the size of novelties being tested (see 

Figure 3-7, “Example of a Displacement Vessel”). It should include an interior baffle that 

reduces wave action when the novelty is inserted and a downward angled overflow spout to 

reduce dripping. Other designs may be used.
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• Thin wire, clamp, or tongs

• Freezer or ice chest and dry ice

• Single-edged razor or sharp knife (for sandwiches only)

• Ice water/kerosene maintained at 1 °C (33 °F) or below

• Indelible marker (for ice pops only)

• Level, at least 152 mm (6 in) in length

• Partial immersion thermometer or equivalent with 1 °C (2 °F) graduations and a − 35 °C to 

+ 50 °C (− 30 °F to + 120 °F) accurate to ± 1 °C (± 2 °F)

• A table top, laboratory-type jack of sufficient size to hold the displacement vessel

• Stopwatch

3.11.2. Test Procedure

1. Follow the procedures in Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” 

sampling plan in the inspection; and select a random sample.

2. Maintain the samples at the reference temperature for frozen products that is specified in 

Table 3-1. “Reference Temperatures for Liquids.” Place the samples in the freezer or ice chest 

until they are ready to be tested, and then remove packages from the freezer one at a time.

3. According to the type of novelty, prepare the sample products as follows:

 *Ice-pop. Mark on the stick(s) with the indelible marker the point to which the ice-pop 

will be submerged in the ice water. (After the ice-pop contents have been submerged, 

remove the novelty to determine the volume of the stick.)

Figure 3-7. Example of a Displacement Vessel.
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 *Cone. Make a small hole in the cone below the ice cream portion to allow air to escape.

 Sandwich. Determine whether the declared volume is (a) the total volume of the novelty 

(that is, including the cookie portion) or (b) the volume of the ice-cream-like portion only. 

If the declared volume is the volume of only the ice-cream-like portion, shave off the 

cookie with a razor or knife, leaving some remnants of cookie to ensure that no ice cream 

is accidentally shaved off. Work quickly, and return the novelty to the freezer before the 

sandwich softens.

 Cup. Remove the cap from the cup.

4. Fill the displacement vessel with ice water until it overflows the spout. Allow it to sit until 

dripping stops. Raise the displacement vessel as necessary and place the graduate beneath the 

spout.

5. Remove a package from the freezer, determine its gross weight, and record it.

6. Submerge the novelty as suggested until it is below the surface level of the water.

 Ice-pop. Use a clamp, tongs, or your fingers to hold the stick(s) and submerge the icepop to the level marked in Step 3 of the Test Procedure.

 Cone. Shape the wire into a loop, and use it to push the cone, headfirst (ice cream portion 

first) into the ice water. Do not completely submerge the cone immediately: let water fill 

the cone through the hole made in Step 3 of the Test Procedure before completely 

submerging the novelty.

 Sandwich or cup. Skewer the novelty with the thin wire or form a loop on the end of the 

wire to push the sandwich or ice cream portion or cup completely below the liquid level.

7. Record the total water volume in the graduate. 

 For a cone or sandwich, record the water volume as the net volume and go to Step 9. 

 For ice-pops or cups, record the water volume in the graduate as the gross volume and go 

to Step 8.

8. Refill the displacement vessel with water to overflowing and reposition the empty graduate 

under the spout. After the cup and novelty contents have been submerged, remove the novelty 

from the cup to determine the volume of the cup. 

 Ice-pop. Melt the ice-pop off the stick or sticks. Submerge the stick or sticks to the line 

marked in Step 3. Record the volume of tare material (i.e., stick) by measuring the water 

displaced into the graduate. The net volume for the ice-pop is the gross volume recorded 

in Step 7 minus the volume of the tare materials in this step. Record this volume as the 

“volume of novelty.” To determine the error in the package, subtract the labeled quantity 

from the volume of novelty.

 Cup. Remove the novelty from the cup. Rinse the cup, and then submerge it in the 

displacement vessel. Small pinholes in the base of the cup can be made to make 

submersion easier. Record the volume of water displaced into the graduate by the cup as 
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the volume of tare material. The net volume for the novelty is the gross volume 

determined in Step 7 minus the volume of the tare materials determined in this step. 

Record this as the net volume of the novelty. To determine the error in the package, 

subtract the labeled quantity from the volume of novelty.

9. Clean and air-dry the tare materials (sticks, wrappers, cup, lid, etc.). Weigh and record the 

weight of these materials for the package.

10. Subtract the tare weight from the gross weight to obtain the net weight and record this value.

11. Compute the weight of the labeled volume for the package using the following formula and 

then record the weight:

Product Density = (product net weight in Step 10) ÷ (the total water volume in Step 7 –

volume of tare material in Step 8)

Weight of labeled volume = (labeled volume) × (Product Density)

12. Repeat Steps 3 through 11 for a second package.

13. If the weight of the labeled volumes in Step 11 for the two packages differs from each other 

by more than one division on the scale, the gravimetric test procedure cannot be used to test 

the sample for compliance. If this is the case, use Steps 3 through 8 for each of the remaining 

packages in the sample to determine their net volumes and package errors. Then go to 

evaluation of results. If the weights of the labeled volumes agree within one division, continue 

to Step 14 to test the rest of the sample using the gravimetric test procedure.*

14. Use Section 2.3.5.1. “Determination of Tare Sample and Average Tare Weight” to determine 

the Average Used Dry tare Weight of the sample.

15. Find the Average Product Density by adding the densities of the product from the two 

packages and dividing the sum by two.

16. Using the weight of labeled volume determined in Step 11, calculate the Average Product 

Weight by multiplying the weight of the labeled volume by the average product density. 

*Average Product Weight = Labeled Volume × Average Product Density

17. Calculate the “nominal gross weight” using the formula:

Nominal Gross Weight = Average Product Weight + Average Used Dry Tare Weight

18. Weigh the remaining packages in the sample.

19. Subtract the nominal gross weight from the gross weight of each package to obtain package 

errors in terms of weight.

Note: Compare the sample packages to the nominal gross weight.

20. Determine the average package error by totaling all package errors and dividing by the number 

of packages in the sample.
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To convert the average error or package error from weight to volume, use the following 

formula:

Package Error in Volume = (Package Error in Weight) ÷ (Average Product Density)

3.11.3. Evaluation of Results

Follow the procedures in Section 2.3.7. “Evaluate for Compliance” to determine lot conformance.

3.12. Fresh Oysters Labeled by Volume

Packaged fresh oysters removed from the shell must be labeled by volume. The maximum amount of 

permitted free liquid is limited to 15 % by weight. (see NIST Handbook 130, Method of Sale of 

Commodities, Section 1.5.2.3. “Fresh Oysters Removed From Shell.”) Testing the quantity of contents of 

fresh oysters requires the inspector to determine total volume, total weight of solids and liquid, and the 

weight of the free liquid.

3.12.1. Test Equipment

• A scale that meets the requirements in Section 2.2. “Measurement Standards and Test 

Equipment”

• Volumetric measures

• Micrometer depth gage (ends of rods fully rounded), 0 mm to 228 mm (0 in to 9 in)

• Strainer for determining the amount of drained liquid from shucked oysters. Use a strainer and 

a slightly smaller bottom receiving pan or tray constructed to the following specifications:

 Sides: 50 mm (2 in)

 Area: 1935 cm2 (300 in2

) or more for each 3.78 L (1 gal) of oysters 

Note: Strainers of smaller area dimensions are permitted to facilitate testing smaller containers.

 Perforations:

Diameter: 6.35 mm (1

/4 in)

Location: 3.17 cm (11

/4 in) apart in a square pattern, or perforations of equivalent area 

and distribution.

• Spanning bar, 25.4 mm × 25.4 mm × 304 mm (1 in × 1 in × 12 in)

• Rubber spatula

• Partial immersion thermometer, 1 °C (2 °F) graduations and a range of – 35 °C to + 50 °C 

(− 30 °F to + 120 °F) accurate to ±1 °C (± 2 °F)

• Level, at least 152 mm (6 in) in length
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• Stopwatch

(Amended 2014)

3.12.2. Test Procedure

Note: Test the oysters at a temperature of 7 °C (± 1 °C) (45 °F [± 2 °F]) 

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection; and select a random sample.

2. Determine and record the gross weight of a sample package.

3. Set the container on a level surface and open it. Use a depth gage to determine the level of fill. 

Lock the depth gage. Mark the location of the gage on the package.

4. Weigh a dry receiving pan and record the weight. Set strainer over the receiving pan.

5. Pour the contents from the container onto the strainer without shaking it. Drain for 

two minutes. Remove strainer with oysters. It is normal for oysters to include mucous (which 

is part of the product) that will not pass through the strainer, so do not force it.

6. Weigh the receiving pan and liquid and record the weight. Subtract the weight of the dry 

receiving pan from the weight of pan and liquid to obtain the weight of free liquid and record 

the value.

7. Clean, dry, and weigh the container and record the tare weight. Subtract the tare weight from 

the gross weight to obtain the total weight of the oysters and liquid and record this value.

8. Determine and record the percent of free liquid by weight as follows:

Note: This handbook provides a worksheet for Determining the Free Liquid and Net Volume of 

Oysters in Appendix C. “Model Inspection Report Forms.”

Percent of free liquid by weight = [(weight of free liquid) ÷ (weight of oysters + liquid)] × 100

or

(f ÷ c) × 100 = Percentage of Free Liquid by Weights

Where:

f = Weight of Free Liquid

c = (Net Weight of Oysters + Liquid)

9. Set up the depth gage on the dry package container as in Step 3. Pour water from the flasks 

and graduate as needed to re-establish the level of fill obtained in Step 3. Add the volumes 

delivered as the actual net volume for the container and record the value. 

Note: Some containers will hold the declared volume only when filled to the brim; they may have been 

designed for other products, rather than for oysters. If the net volume is short measure (per Step 9), 
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determine if the container will reach the declared volume only if filled to the brim. Under such 

circumstance, the package net volumes will all be short measure because the container cannot be filled to 

the brim with a solid and liquid mixture. A small headspace is required in order to get the lid into the 

container without losing any liquid.

(Amended 2014)

3.12.3. Evaluation of Results

Follow the procedures in Section 2.3.7. “Evaluate for Compliance” to determine lot conformance.

3.13. Determining the Net Contents of Compressed Gas in Cylinders

These procedures are for industrial compressed gas. Compressed gas may be labeled by weight (for 

example, Liquefied Petroleum [LP] gas, or carbon dioxide) or by volume. Acetylene, liquid oxygen, 

nitrogen, nitrous oxide, and argon are all filled by weight. Acetylene is sold by liters or by cubic feet. 

Helium, gaseous oxygen, nitrogen, air, and argon are filled according to pressure and temperature tables.

Checking the net contents of compressed gas cylinders depends on the method of labeling; those labeled 

by weight are generally checked by weight. Cylinders filled by using pressure and temperature charts must 

be tested using a pressure gage that is connected to the cylinder. The volume is determined using the 

pressure and temperature of the cylinder.

Safety Precautions:

Be aware of the hazards of the high pressure found in cylinders of compressed gas. An inspector should 

handle compressed gas only if the inspector has been trained and is knowledgeable regarding the product, 

cylinder, fittings, and proper procedures (see Compressed Gas Association [CGA] pamphlet P-1, “Safe 

Handling of Compressed Gases in Containers,” for additional information). Additional precautions that 

are necessary for personal safety are described in the CGA Handbook of Compressed Gases. All personnel 

testing compressed gases should have this manual for reference and be familiar with its contents. It is 

essential that the inspector be certain of the contents before connecting to the cylinder. Discharging a gas 

or cryogenic liquid through a system for which the material is not intended could result in a fire and/or 

explosion or property damage due to the incompatibility of the system and the product. Before connecting 

a cylinder to anything, be certain of the following:

1. Always wear safety glasses.

2. The cylinder is clearly marked or labeled with the correct name of the contents and that no 

conflicting marks or labels are present. Do not rely on the color of the cylinder to identify the 

contents of a cylinder. Be extremely careful with all gases because some react violently when 

mixed or when coming in contact with other substances. For example, oxygen reacts violently 

when it comes in contact with hydrocarbons.

3. The cylinder is provided with the correct Compressed Gas Association (CGA) connection(s) for 

the product. A proper connection will go together smoothly; so excessive force should not be 

used. Do not use an adapter to connect oxygen to non-oxygen cleaned equipment. When a 

cylinder valve is opened to measure the internal pressure, position the body away from the 

pressure gage blowout plug or in front of the gage if the gage has a solid cast front case. If the 

bourdon tube should rupture, do not be in a position to suffer serious injuries from gas pressure 

or fragments of metal.
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Note: The acetone in acetylene cylinders is included in the tare weight of the cylinder. Therefore, as 

acetylene is withdrawn from the cylinder, some acetone will also be withdrawn, changing the tare 

weight.

4. Thoroughly know the procedure and place emphasis on safety precautions before attempting any 

tests. Do not use charts referred to in the procedure until the necessary training has been 

completed. When moving a cylinder, always place the protective cap on the cylinder. Do not 

leave spaces between cylinders when moving them. This can lead to a “domino” effect if one 

cylinder is pushed over.

5. Open all valves slowly. A failure of the gage or other ancillary equipment can result in injuries 

to nearby persons. Remember that high gas pressure can propel objects with great force. Gas 

ejected under pressure can also cause serious bodily injuries if someone is too close during release 

of pressure.

6. One of the gages will be reserved for testing oxygen only and will be prominently labeled “For 

Oxygen Use Only.” This gage must be cleaned for oxygen service and maintained in that “clean” 

condition. The other gage(s) may be used for testing a variety of gases if they are compatible with 

one another.

7. Observe special precautions with flammable gas in cylinders in addition to the several precautions 

necessary for the safe handling of any compressed gas in cylinders. Do not “crack” cylinder 

valves of flammable gas before connecting them to a regulator or test gage. This is extremely 

important for hydrogen or acetylene.

3.13.1. Test Equipment

• Scale that meets the requirements in Section 2.2. “Measurement Standards and Test 

Equipment.” Use a wooden or non-sparking metal ramp to roll the cylinders on the scale to 

reduce shock loading.

• Two calibrated precision bourdon tube gages or any other approved laboratory-type pressuremeasuring device that can be accurately read within plus or minus 40 kPa (5 psi). A gage

having scale increments of 200 kPa (25 psi) or smaller shall be considered as satisfactory for 

reading within plus or minus 40 kPa (5 psi). The range of both gages shall be a minimum of 

0 kPa to 23 MPa (0 psi to 5000 psi) when testing cylinders using standard industrial cylinder 

valve connections. These standardized connections are listed in “CGA Standard V-1, Standard 

for Compressed Gas Cylinder Valve Outlet and Inlet Connections for use with Gas Pressures 

up to 21 MPa (3000 psi).” For testing cylinders with cylinder valve connections rated for over 

21 MPa (3000 psi), the test gage and its inlet connection must be rated at 14 MPa (2000 psi) 

over the maximum pressure that the connection is rated for in CGA V-1. 

Notes: 

(1) There are standard high-pressure industrial connections on the market that are being used 

up to their maximum pressure of 52 MPa (7500 psi).

(2) Any gage or connectors used with oxygen cylinders must be cleaned for oxygen service, 

transported in a manner which will keep them clean and never used for any other gas 

including air or oxygen mixtures. Oxygen will react with hydrocarbons and many foreign 

materials that may cause a fire or explosion.
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(3) Use a separate gage and fitting for each gas to be tested. If adapters must be used, do not 

use on oxygen systems.

• An approved and calibrated electronic temperature measuring device or three 

calibrated liquid-in-glass thermometers having either a digital readout or scale division 

of no more than 1 °F (0.5 °C). The electronic device equipped with a surface 

temperature sensor is preferred over a liquid-in-glass thermometer because of its 

shorter response time.

• Two box-end wrenches of 29 mm (11

/8 in) for oxygen, nitrogen, carbon dioxide, argon, 

helium, and hydrogen and 22 mm (7

/8 in) for some sizes of propane. All industrial CGA 

connections are limited to these two hex sizes. Avoid using an adjustable wrench 

because of the tendency to round the edges of the fittings, which can lead to 

connections not being tightened properly.

3.13.2. Test Procedures

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection; select a random sample.

2. The cylinder should be marked or stenciled with a tare weight. The marked value may or may 

not be used by the filling plant when determining the net weight of those cylinders sold or 

filled by weight. If there is a tare weight marked on the net contents tag or directly on the 

cylinder, then an actual tare weight was determined at the time of fill. If there is no tare weight 

marked on a tag or on the cylinder, then the stamped or stenciled tare weight is presumed to 

have been used to determine the net contents.

Note: Check the accuracy of the stamped tare weights on empty cylinders whenever possible. 

The actual tare weight must be within (a) 1/2 % of the stamped tare weight for 9.07 kg (20 lb) tare 

weights or less or (b) 1

/4 % of the stamped tare weight for greater than 9.07 kg (20 lb) tare weights. 

(see NIST Handbook 130, Method of Sale Regulation, Section 2.16. “Compressed or Liquefied 

Gases in Refillable Cylinders.”) The cap is not included in the tare weight.

3. Place cylinder on scale and remove protective cap. Weigh the cylinder and determine net 

weight, using either the stamped or stenciled tare weight, or the tare weight marked on the 

tag. Compare actual net weight with labeled net weight, or use the actual net weight to look 

up the correct volume declaration (for Acetylene Gas), and compare that with the labeled 

volume.

Note: Most producers will replace acetone in the cylinder before the cylinder is refilled, filling 

the cylinder with acetone to the stamped tare weight. Other producers, although not following 

recommended procedures, do not replace the acetone until it drops to a predetermined weight. In 

the latter situation, the refilling plant must note the actual tare weight of the cylinder and show it 

on the tag containing the net content statement or on the cylinder itself. Refer to tables for 

acetylene if necessary (if the acetylene is labeled by volume).
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1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection; select a random sample.

2. Determine the temperature of the cylinders in the sample. Place the thermometer 

approximately halfway up a cylinder in contact with the outside surface. Take the temperature 

of three cylinders selected at random and use the average temperature of the three values.

3. Using the appropriate pressure gage, measure the pressure of each cylinder in the sample.

4. Determine the cylinder nominal capacity from cylinder data tables or from the manufacturer. 

(These tables must be obtained in advance of testing.)

5. The SCF/CF volume of compressed gases (e.g., oxygen, argon, nitrogen, helium, or hydrogen) 

shall be determined using NIST Standard Reference Database 23 “Reference Fluid 

Thermodynamic and Transport Properties Database” (REFPROP). (see www.nist.gov/srd/ref

prop) (Note: Weights and measures officials should contact the NIST Office of Weights and 

Measures at (301) 975-4004 or owm@nist.gov for access to the database.)

6. Multiply the cylinder nominal capacity by the value (SCF/CF) obtained from the content tables. 

This is the actual net quantity of gas.

7. Subtract the labeled net quantity from the actual net quantity to determine the error.

3.13.3. Evaluation of Results

Follow Section 2.3.7. “Evaluate for Compliance” to determine lot conformance.

3.14. Firewood – Volumetric Test Procedure for Packaged Firewood with a Labeled 

Volume of 113 L [4 ft3] or Less and Stacked Firewood Sold by the Cord or Fractions 

of a Cord.

Unless otherwise indicated, take all measurements without rearranging the wood or removing it from the 

package. However, if the layers of wood are crosshatched or not ranked in discrete sections in the package, 

remove the wood from the package, re-stack, and measure according to the procedures described in this 

section. For boxed firewood, it is the volume of the wood in the box that is determined not the volume of 

the box.

(Amended 2016)

3.14.1. Test Equipment 

Linear Measurement

The maximum value of graduations on a ruler or tape shall be equal to or less than:

For Testing SI Units U.S. Customary Units

Packaged Firewood 1 mm 1/16 in (0.0625 in)

Stacked Firewood 0.5 cm 1/8 in (0.125 in)
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Other Equipment: 

Except where a long tape measure is needed for measuring stacks of wood and unless otherwise 

noted below, a precision tempered steel ruler should be used for linear measurements. Current 

calibration certificates issued by a NIST recognized or accredited laboratory should be available 

for all measuring devices. 

• To test boxes of firewood, use a straightedge and a 150 mm (6 in) tempered steel pocket 

ruler to measure the box headspace. A rigid 610 mm (24 in) tempered steel ruler is required 

to measure piece length and the dimensions of the box.

• To test bundles of firewood, use a rigid 610 mm (24 in) tempered steel ruler to measure 

typical piece length. If the circumference based auditing method is to be conducted, a 

precision 610 mm (24 in) diameter (pi) tape or flexible steel tape with 1 mm (1

/16 in) 

graduations may be used to approximate the package volume for screening and audit 

purposes.

For testing stacks of firewood, a precision tape or long tape measure is used. For testing bundles 

and bags of firewood, the following equipment and materials are used in addition to the linear 

measures listed above:

• Binding Straps: Straps with ratchet type closures are easily tightened to secure the wood 

tightly. The binding straps are used to hold wood bundles together if the bundles need to 

be removed from the package/wrapping material. 

• Graph Paper: 279.4 mm × 431.8 mm (11 in × 17 in) with 0.5 centimeter or 1/4 inch squares. 

This paper is used for tracing and calculating the areas of the ends of a bundle of firewood. 

Prior to using any graph paper use a calibrated ruler to verify the dimensions of squares at 

several random points across the page. 

• Ruler: 300 mm (12 in) with 0.5 cm (1/4 in) graduations. This ruler is used with the graph 

paper to calculate the area of the bundle ends. 

(Amended 2016)

3.14.2. Test Procedure

General Instructions

• When testing packaged firewood Section 2.3.1. “Define the Inspection Lot.” Use a 

“Category A” sampling plan in the inspection; and select a random sample.

• Measurements shall be read to the smallest graduation on the ruler or tape. Round any value 

that falls between two graduations up to the higher value except when making headspace depth 

measurements in the test procedure for boxes where a value falling between two graduations is 

rounded down.

• Samples for Length. Use Table 3-5. “Minimum Number of Pieces to be Measured for Length” 

to determine the minimum number of pieces to measure to determine the average length of the 

firewood pieces in a package or stack.
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Table 3-5.

Minimum Number of Pieces to be Measured for Length

Volume Minimum Number of Pieces 

to be Measured for Length* 1. Packaged firewood 453 L (16 cu ft) (1

/8 cord) or less

a. For packages with 12 pieces or less All

b. For packages with 13 to 50 pieces At least 12 pieces

c. For packages with more than 50 pieces At least 24 pieces

2. Stacked wood At least 12 pieces for each 

1

/2 cord or fraction thereof

*Note: While the packages of firewood to be included in the sample must be selected using the 

random sampling techniques described in NIST Handbook 133, Section 2.3.4. “Random Sample 

Selection,” those techniques are not used in selecting the individual pieces for measurement of 

length. Since the packages were selected at random, the assumption is made that the length of 

any piece selected for measuring is generally representative of the other pieces that the packer 

cut or selected for inclusion in the package under inspection. When selecting pieces of wood for 

measurement, take them from different locations in the package or stack so they are representative 

of the total amount of wood under test.

• Measuring Procedures for Length. – Use the instructions and graphics in Table 3-6. 

“Determining Piece Length” when measuring the length of the pieces to determine the average 

length of a piece of firewood based on its shape in a package or stack. If a piece of wood does 

not appear to fall within the examples shows, measure it as if it were an irregular shape and 

take three or more measurements and average them. 

Table 3-6.

Determining Piece Length 

(a) Uniform Shapes

Errors in the length measurement can result in a significant volume errors especially with the small 

quantities typical of packaged wood. When the pieces are generally cut in a uniform manner, a 

single measurement along the center line of the longitudinal axis is used to determine piece length. 

Take the measurement along a straight line between two points over solid wood. 

(i) Most wood pieces are cut perpendicular to their longitudinal axis so one measurement 

taken from the face of one end to the face of the other end will provide an accurate 

length determination. 
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Table 3-6.

Determining Piece Length 

(ii) On pieces of wood with “reverse bias” and “bias” end cuts estimate where the center

line of the piece is and then measure to these points as shown below. The intent of this 

measurement is to determine an “average” length that is assumed to fall along the center 

line of the piece. The top piece is an example of a “reverse” bias cut.

The bottom piece is an example of a bias cut

(b) Irregular Shapes

When the pieces have irregular shapes, cuts, or shattered ends, it is necessary to take at least three 

measurements and average the results to obtain the length of the piece. Take the measurements 

along a straight line between two points which cover solid wood that appear to be the shortest and 

longest dimensions and a third measurement at or near the center line of the piece.

(iii) This piece has a bias cut end on the left and an irregular end on the right. The 

measurements are taken at the longest and shortest points where the line crosses over 

solid wood. The lowest measurement (dotted line over the air space) is not used because 

it does not cross wood. Only the three upper measurements are used to calculate the 

average length for this piece unless additional measurements across solid wood are 

taken.
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Table 3-6.

Determining Piece Length 

(iv) This is a piece with a bias cut on the left end and irregular end on the right. Note how 

the measurements are taken at the longest and shortest points where the line crosses over 

solid wood. The lowest measurement (the dotted line) would not be used because it 

does not crossover wood. 

(v) This piece of wood has a “shattered end.” Shattering occurs when wood is stressed 

beyond its breaking point and the end is not trimmed. The inspector will take additonal 

measurements to account at the shortest point of the voids and longest points at the 

extensions. In this example, five measurements were taken and averaged to account for 

the voids and extensions. 

Note: A packer may place wrapped bundles of firewood in boxes for ease of handling as well as for display 

on retail store shelves. When a box contains a bundle of wrapped firewood, the volume of the bundle is 

verified using the test procedure in c. “Bundled and Bagged Firewood.” 

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection; and select a random sample.

2. Open the box to determine the average height of wood.

3. Measure the internal height of the box. (see Figure 3-8. “Measuring the Internal Height of

the Box.”)
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4. Determining the Height of the Wood. Take at least five measurements spaced at intervals 

along each end and center of the wood stack (record as “d1, d2. . .etc.; taking at least 

15 measurements). (see Figure 3-9. “Top View of the Box” – Measure at cross bars and 

Figure 3-9a. “Examples of the Headspace Measurement.”) Measure from the bottom of a 

straightedge placed across the top of the box to the highest point on the wood (round the 

measurements down to the nearest 0.5 cm [1

/8 in] or less). Calculate the average height of 

the stack by averaging these measurements and subtracting the result from the internal 

height of the box using the following formula:

Average Height of Wood Stack =

(Internal Height of Box) − (Sum of Depth Measurements ÷ Number of Measurements)

Figure 3-9. Top View of the Box. 

Measure at the cross bars.

Figure 3-8. Measuring the Internal Height of

the Box.
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Figure 3-9a. Examples of the Headspace Measurement.

5. Width of Wood Stack. Open the box and measure the width of the wood stack. Take at least 

five measurements at intervals spaced along the length of the stack. Average these values to 

obtain an Average Width of Wood Stack. (see Figure 3-10. “Top View of the Box,” and 

Figure 3-10a. “Measuring the Width of the Firewood in a Box.”) You are measuring the 

width of the wood, not the width of the box.

Average Width of Wood Stack = (W1 + W2 + W3 + W4 + W5) ÷ 5

Figure 3-10. Top View 

of the Box. Measure at 

crosslines.
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Figure 3-10a. Measuring 

the Width of the Firewood 

in a Box.

6. Individual Piece Length. Remove the wood from the package and measure the length of 

each piece of wood (see Table 3-5. “Minimum Number of Pieces to be Measured for 

Length”). If the piece of wood is uniform in shape, take at least one point-to-point 

measurement along the center line of the longitudinal axis (see Table 3-6. “Determining 

Piece Length, (a) Uniform Shapes” for examples) and record the value. 

If the wood is irregularly shaped (see Table 3-6. “Determining Piece Length, (b) Irregular 

Shapes” for examples), take at least three measurements along a straight line between two 

points crossing solid wood that appear to be the shortest and longest dimensions, and a third 

at or near the center line of the piece. Calculate the average of the measurements to obtain 

the Average Individual Piece Length and record the length of the piece. 

To determine Average Individual Piece Length (AIPL) of irregularly shaped pieces:

AIPL = (L 1 + L2 + L3) ÷ 3

After all pieces are measured, total the lengths and divide that total by the number of 

samples to obtain the Average Piece Length for the package.

To determine Average Piece Length (APL) for the package:

APL = (L1 + L2 + L3 + Ln) ÷ (Number of Pieces in Sample)

7. Use the average values for height, width, and length to calculate the volume of wood in the 

box.

Volume in liters = (height in mm × width in mm × length in mm) ÷ 1,000,000

Volume in cubic feet = (height in inches × width in inches × length in inches) ÷ (1728)

Note: 1 cubic foot = 1728 in3

, 1 cubic liter = 1,000,000 L3
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8. For boxes of wood that are packed with the wood ranked in two discrete sections 

perpendicular to each other, calculate the volume of wood in the box as follows: 

(1) determine the average height, width, and length as in 1, 2, and 3 above for each discrete 

section, compute total volume, and (2) total the calculated volumes of the two sections. 

Compute total volume by adding Volume 1 (V1) and Volume 2 (V2) according to the 

following formula. 

Total Volume = V1 + V2 

This illustration shows how the width of the firewood is measured when two perpendicular 

stacks of firewood are in a box. The height, width, and length of the pieces are used to 

determine the volume of the separate stacks which are then added together to obtain the volume 

of wood in the package.

Bulk deliveries of firewood are typically required by law or regulation to be on the basis of cord 

measurements. The “cord” is defined as the amount of wood contained in a space of 128 ft3 when the wood 

is ranked and well stowed. The standard dimensions for a cord of wood are 4 ft (height) × 4 ft

(width) × 8 ft (length) but wood may be stacked and measured in any configuration. See Figure 3-11. “A 

Cord of Wood” for an illustration of how a cord may be stacked.

1. Wood Delivered to a Consumer. If a delivery ticket or sales receipt is available (these are often 

required by state regulation), review the delivery ticket or sales receipt and determine the quantity 

Volume 1 Volume 2

Figure 3-11. A Cord of 

Wood.

A cord of wood measures 

Length (8 ft) × Width (4 ft) × 

Height (4 ft). 
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delivered. Identify the wood to be measured and verify the wood delivered was not mixed with 

wood that was already present at the location. Also, determine if the delivery was partial or 

complete (i.e., no additional deliveries are expected) and if any of the delivered wood has been 

used.

If necessary, stack the firewood in a ranked and well-stowed geometrical shape that facilitates 

volume calculations (i.e., rectangular). Any voids that will accommodate a piece of wood in the 

stack shall be deducted from the measured volume.

Note: The length measurements of the individual pieces may be made during the stacking process.

2. Determine the Average Measurements of the Stack. The number of measurements for each 

dimension given below is the minimum that should be taken.

 Height of Stack. A height measurement is the vertical distance between the top edge of a piece 

of wood in the top row and the bottom edge of a piece of wood on the bottom row. Start at one 

end of the front of the stack; measure the height of the stack at five equally spaced intervals 

(e.g., approximately 18 in to 24 in) along the length of stack. If the length of the stack is over 

10 ft, take additional height measurements at equally spaced intervals along its length. If the 

height of the stack varies significantly (e.g., the pieces are stacked in peaks along the length of 

the stack), take additional height measurements. Calculate and record the average height for 

the front of the stack. Repeat the same height measurement procedure along the back of the 

stack and then calculate and record the average height for the back of the stack. Calculate the 

average height of the stack by averaging the two results. If the wood to be measured is stacked 

on a slope, take the height measurements at right-angles to the slope. 

Average HeightFront = (h1 + h2 + h3 + h4 + h5) ÷ 5

Average HeightBack = (h1 + h2 + h3 +h4 + h5) ÷ 5

Average Height of Stack = Average HeightFront + Average HeightBack ÷ 2

Average Height Measurement (front and back)

 Length of Stack. A length measurement is the horizontal distance between the left edge of a 

piece of wood on the left side of the stack and the right edge of a piece of wood on the opposite 

side of the stack. Start at either side of the stack; measure the length of the stack in five equal 

intervals. Calculate and record the average length. If the length of the stack varies significantly 
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(e.g., the ends of the stack bulge out along the height of the stack), take additional 

measurements.

Average Length Measurement (front and back)

 Calculate and record the Average Length or the Front of the Stack. Repeat the length 

measurement procedure along the back of the stack and then calculate and record the average 

length for the stack.

Average Stack LengthFront = (l1 + l2 + l3 + l4 + l5) ÷ 5

Average Stack LengthBack = (l1 + l2 + l3 + l4 + l5) ÷ 5

Average Stack Length = (Average LengthFront + Average LengthBack ) ÷ 2

 Width of Stack. This is equal to the Average Length of Pieces that make up the Width of the 

Stack. Refer to Table 3-5. “Minimum Number of Pieces to be Measured for Length” to 

determine how many pieces are to be measured. This dimension is calculated by averaging the 

length of individual pieces of wood in the stack and multiplying it by the number of rows. The 

wood can be stacked in a single or multiple rows. If the wood is stacked in several rows deep, 

select a representative random sample from each row. If the wood needs to be stacked, measure 

the pieces prior to stacking. If the wood is already stacked, select the pieces at random by 

moving up and down and across the stack. If it is necessary to remove the wood from a stack 

to measure the individual piece lengths, always complete the height and length measurements 

before disturbing the stacked wood.

Width of Stack = Average Piece Length (APL) × Number of Rows

3. Individual Piece Length. Table 3-5. “Minimum Number of Pieces to be Measured for Length” 

requires that at least 12 pieces of wood be measured for every half cord estimated to be in the stack. 

 If the wood is uniform in shape, take at least one point-to-point measurement along the center 

line of the longitudinal axis (see Table 3-6. “Determining Piece Length, (a) “Uniform Shape” 

for examples) and record the value. 

 If the wood is irregularly shaped (see Table 3-6. “Determining Piece Length, (b) Irregular 

Shape” for examples), take at least three measurements along a straight line between two points 

crossing solid wood that appear to be the shortest and longest dimensions, and a third at or near 
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the center line of the piece. Calculate the average of the measurements to determine Average 

Individual Piece Length (AIPL) of irregularly shaped pieces: 

AIPL = (L1 + L2 + L3) ÷ 3

 After all the pieces are measured, total the lengths and divide the total by the number of samples 

to obtain the Average Piece Length for the stack. To determine Average Piece Length (APL) 

for the package: 

APL = (L1 + L2 + L3 + ... Ln) ÷ (Number of Pieces in Sample)

4. Calculate Volume.

Volume in liters = (Avg. Height [cm] × Avg. Width [cm] × Average Piece Length [cm]) ÷ 1000

Volume in cubic feet = (Avg. Height [in] × Avg. Width [in] × Average Piece Length [in]) ÷ 1728

5. Supplemental Measurement of Stacked Wood:

 Volume of a Triangle Stack of Wood (see Figure 3-12. “Triangular Stack of Wood”). To 

calculate the volume of a triangular stack, take at least two measurements (one each side) of 

the height and length, and five measurements of the width of the stack and average each result. 

Use this formula to calculate the volume.

Volume of Triangular Stack = (Avg. Height × Avg. Length of Base × Avg. Width) ÷ 2

 The volume of the triangular stack may be added to the volume of other stacks.

Figure 3-12. Triangular Stack of Wood.
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3.14.3. Field Audit Procedure – Bundled and Bagged Firewood

A circumference estimating method can be used for quickly identifying potentially short measure 

bundles. The procedure is based on measuring the circumference of the package ends and calculating 

the areas without using graph paper. It shall be used for audit purposes only and must not be used for 

official inspection. 

1. After the bundle or bag is secured, use a flexible measuring tape to measure the circumference 

near each end of the bundle or bag of firewood (see Figure 3-13a. “Strapping the Ends of a 

Bundle”). Using one movement, extend the measuring tape around the end of the bundle or 

bag to obtain its circumference (see Figure 3-13b. “Measuring the Circumference of the 

Bundle”). The tape must be pulled tight. If the wood at the ends of a bag or bundle is not 

accessible due to plastic wrapping, the wrapping should be moved away from the ends so the 

measuring tape can be placed tightly around the bundle so circumference measurements can be 

taken.

Figure 3-13a. Strapping the Ends of a 

Bundle.

Figure 3-13. Firewood Bundle and Bag
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Note: The tape used has a blank end so the “0” line is visible immediately under the 10 in mark.

2. Calculate the Average Circumference:

Average Circumference = (circumference1 + circumference2) ÷ 2

Example: 

If circumference1 is 34 in and circumference2 is 33.75 in then:

Average Circumference: 34 + 33.75 ÷ 2 = 33.875 in

3. Calculate the Radius:

Radius = Average Circumference ÷ 2π

Where: π = 3.1415

Example: 

radius = 33.875 ÷ (2 × π or 6.283) = 5.39 in

4. Calculate the Average Area 

Average Area = πr2

Example: 

Average Area = 3.1415 × 5.392 (or 29.06) = 91.3 in2

5. Calculate the Average Length of the Pieces:

Average length of the pieces of wood – measure the length of several pieces of wood in 

the bundle or bag. Measurements are to be taken from center to center at the end of each 

piece. 

Then calculate the average:

Average length = sum of the length of all pieces ÷ number of pieces

Figure 3-13b. Measuring the Circumference 

of the Bundle. 

At the point of the arrow, the circumference 

of the bundle is 2 ft 10 in (34 in).
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6. Calculate Volume:

Volume in liters = (Average area [cm2] × Average Length [cm]) ÷ 1000

Volume in cubic feet = (Average Area [in2] × Average Length [in]) ÷ 1728

Example: 

Assume the Average Length of the Pieces is 16 in and Average Area is 91.3 in2

Bundle Volume = 91.3 in2 × 16 in = 1460 in3 or 0.84 ft3

If results indicate that the sample fails, conduct further testing using the reference test procedure 

for bundles and bags. Do not take any legal action based solely on this audit procedure.

(Amended 2016)

3.14.4. Test Procedure - Bundled and Bagged Firewood

1. Follow Section 2.3.1. “Define the Inspection Lot.” Use a “Category A” sampling plan in the 

inspection; and select a random sample.

2. Average Area of Bundle Ends: 

 Place a binding strap around each end of the bundle (or bag of firewood) to prevent 

movement of the pieces during test. Place the straps approximately 10 cm (4 in) from the 

ends (see Figure 3-14. “A Tightly Wrapped Bundle with Straps Placed at 10 cm [4 in]”)

and tighten them securely.

Test Note: To test a bag of firewood remove the firewood from the bag and form a compact 

bundle and strap it as shown in Figure 3-14. “A Tightly Wrapped Bundle with Straps Placed at 

10 cm (4 in),” and follow the procedures for measuring a bundle of firewood.

Notice: Do not use shrink wrap or packaging to 

define the perimeter because it can result in 

inaccurate measurements. 

If necessary, trim the shrink wrap back from the 

ends to allow for the bundle to sit flat on the 

graph paper.

Figure 3-14. A Tightly Wrapped Bundle with 

Straps Placed at 10 cm (4 in).
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 Set one end of the bundle or bag of firewood on graph paper large enough to cover the end 

completely. Draw a line around the outside of the wood perimeter on the graph paper using 

a sharp point marking pen (see Figure 3-15. “Tracing Perimeter of the Wood”).

 Count the number of square centimeters or square inches that are enclosed within the 

perimeter line. Determine portions of square centimeters or square inches not completely 

within the perimeter line to the nearest one-quarter square inch. Repeat this process on the 

opposite end of the bundle or bag.

Figure 3-15. Tracing the Perimeter of the Wood.

Examples:

(1) Using 1/4 sq in graph paper and a ruler with 1/4 in graduations, large blocks of the area 

within the perimeter are quickly measured. This is done by using the ruler to determine 

the length and then width of the area which are each divided by 0.25 (1

/4 in) {or multiply 

4 × 7.25} to obtain the number of blocks in that dimension. These two values are 

multiplied to obtain the total number of blocks enclosed in the area. The areas in the 

partially covered blocks are rounded up or down to the nearest 1

/4 in by enclosing the 

whole square and placing an “x” in the partial spaces which are included in the blocks 

where the area has been rounded up. One reason for squaring the graph squares is to 

simplify the counting. 

(2) Use a ruler to count graph squares, the rulers as shown in Figure 3-16. “Perimeter of 

a Bundle as Defined by the Wood” indicate the dimensions of the square are 

71

/4 × 73/4 in. To obtain the number of blocks divide 7.25 by 0.25 {or multiply 4 × 7.25}.

To obtain the number of blocks along the left hand line (7.25 ÷ 0.25 = 29). The bottom 

line measures 73

/4 in so 7.75 ÷ 0.25 = 31 {or 4 × 7.75 = 31}. Multiple the two values to 

obtain the total number of squares within the area which is: 29 × 31 = 899. To obtain 

square inches divide 899 by 16 (the number of 1

/4 in graph squares in a square inch) or 

899 ÷ 16 = for area of 56.19 in2 for this area of the bundle. 
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(3) Continue to divide the area into blocks to make counting easier and then count the 

blocks in the remaining areas and sum these values to obtain the total. (see the example 

in Figure 3-17. “Perimeter of a Bundle of as Defined by the Wood.”) The total number 

of blocks was calculated by adding: 

46 + 45 + 899 + 25 + 8 + 54 = 1177 squares ÷ 16 = 73.56 sq in

for this end of the bundle. 

Calculate the Average Area: Average Area = (Area1 + Area2) ÷ 2

Figure 3-16. Perimeter of a Bundle as Defined by the Wood.

3. Average Length of the Pieces of Wood. Individual piece length, remove the wood from the 

package and measure the length of each piece of wood (see Table 3-5. “Minimum Number of 

Pieces to be Measured for Length” for the number of pieces to be measured.) If the piece of 

wood is uniform in shape, take at least one point-to-point measurement along the center line of 

the longitudinal axis (see Table 3-6. “Determining Piece Length,” (a) Uniform Shapes for 

examples) and record the value. 

 If the wood is irregularly shaped (see Table 3-6. “Determining Piece Length,” (b) Irregular 

Shapes for examples), take at least three measurements along a straight line between two 

points crossing solid wood that appear to be the shortest and longest dimensions, and a 

third at or near the center-line of the piece. Calculate the average of the measurements to 

obtain the Average Individual Piece Length and record the length of the piece. 

To determine Average Individual Piece Length (AIPL) of irregularly shaped pieces:

AIPL = (L1 + L2 + L3) ÷ 3
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Note: If length measurements are made in millimeters divide the total by 10 to obtain 

centimeters.

 After all pieces are measured, total the lengths and divide that total by the number of 

samples to obtain the Average Piece Length for the package.

To determine Average Piece Length (APL) for the package:

APL = (L1 + L2 + L3 + ... Ln) ÷ (Number of Pieces in Sample)

4. Use the average values for height, width, and length to calculate the volume of wood in the 

bundle or bag

 Calculate Volume:

Volume in liters = (Average Area [cm2

] × Average Length [cm]) ÷ 1000

Volume in cubic feet = (Average Area [in2

] × Average Length [in]) ÷ 1728

Note: 1 Cubic Foot = 1728 in3

, 1 L3 = 1000 cm

(Amended 2016)

3.14.5. Evaluation of Results

Follow Section 2.3.7. “Evaluate for Compliance” to determine lot conformance.

Note: Specified in Appendix A, Table 2-10. “Exceptions to the Maximum Allowable Variations for 

Textiles, Polyethylene Sheeting and Film, Mulch and Soil Labeled by Volume, Packaged Firewood and 

Stove Wood Labeled by Volume, and Packages Labeled by Count with 50 Items or Fewer, and Specific 

Agricultural Seeds Labeled by Count.”

3.15. Test Procedure for Verifying the Useable Volume Declaration on Packages of Animal 

Bedding

3.15.1. Test Equipment

• Calculator or spreadsheet software

• Standard Package Report Form – Animal Bedding 

• Measurement Grid and Package Error Worksheet for Cylindrical and Square or Rectangular 

Test Measures

• Permanent ink marking pen

• Knife or razor cutter (for use in opening packages and unwrapping shrink-wrapped pallets in 

warehouses)

• Cellophane tape, Duct tape (for repairing chutes and sealing packages)

• Polyethylene bags (49 L to 113.5 L [13 gal to 30 gal]) (to hold product once it is uncompressed)
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• Rigid Rulers – Starrett or equal with 1.0 mm graduations. The edges of a ruler used with a 

measuring frame must be straight and the edges must be the zero point. 

 300 mm (12 in)

 500 mm (19.5 in)

 1 m (39 in) 

• Tarp – canvas 3 m × 3 m (10 ft × 10 ft) 

• Broom and dust pan

• Levels – for verifying the level of the test measure and taking headspace readings.

 152 mm (6 in) Bubble Level 

 1 m (40 in) Carpenter Level

• Scale 15 kg (30 lb) (only used if the audit procedure is utilized.) 

• Chutes for uncompressing and pouring the bedding into a test measure

• Test Measures (see Table 3-8. “Test Measures for Animal Bedding”)

Table 3-7. 

Recommended Chute Dimensions

Nominal Capacity Height Width Length

70 L (2.5 ft3) 254 mm (10 in) 228 mm (9 in) 1219 mm (48 in)

100 L (3.5 ft3) 254 mm (10 in) 279 mm (11 in) 1397 mm (55 in)

170 L (6 ft3) 279 mm (11 in) 355 mm (14 in) 1727 mm (68 in)

240 L (8.5 ft3) 304 mm (12 in) 406 mm (16 in) 2006 mm (79 in)

283 L (10 ft3) 304 mm (12 in) 406 mm (16 in) 2286 mm (90 in)

Note: 

Chutes (see Illustration 1. Testing Chutes) may be constructed using hinges and pins so that they lie flat 

for transporting. They can be constructed of sheet metal or with other slick surface material which 

enable the bedding to flow easily. The construction of the chutes used in this study allows the sides to 

move in or out slightly so that the bedding does not become clogged at the outlet. The heights and 

lengths may be adjusted slightly to fit into vehicles for transport but the widths should not be reduced 

because narrowing the opening can restrict material flow and result in “bridging” where the bedding 

collects and creates a block. Also, the width should be kept smaller than the opening of the test measure 

so that spillage does not occur during pouring. 
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Table 3-8. 

Test Measures for Animal Bedding NOTES: a, b, c, and d

Only Interior Dimensions are Used for Volume Calculations.

Must Be Calibrated with Traceable Measurement Standards Prior to Use.

Rectangular Test Measures 

Actual 

Volume of the 

Measure b & d

Interior Wall Dimensions

Surface Area

Marked 

Increments 

on Ruler

Increment 

Volume Length Width Heightd

31.9 L

1.13 ft3

213.4 mm

(8.4 in)

203.2 mm

(8 in)

736.6 mm

(29 in)

43 362 mm2

(67.2 in2)

12.7 mm

(0.5 in)

550.6 mL*

0.55 L

(33.6 in3)

28.3 L

1 ft3

304.8 mm 

(12 in)

304.8 mm 

(12 in)

304.8 mm 

(12 in)

92 903 mm2

(144 in2

)

1.18 L**

(72 in3)

63.7 L

2.25 ft3

304.8 mm 

(12 in)

304.8 mm 

(12 in)

685.8 mm

(27 in)

406.4 mm

(16 in)

228.6 mm

(9 in)

685.8 mm

(27 in)

92 L

3.25 ft3

304.8 mm 

(12 in)

304.8 mm 

(12 in)

990.6 mm

(39 in)

406.4 mm

(16 in)

228.6 mm

(9 in)

990.6 mm

(39 in)

*1.0 mm = 43 mL (2.6 cu in) 

** 1.0 mm = 92 mL or 0.09 L (5.6 cu in) 

Illustration 1. Testing Chutes
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Square Test Measures

Actual Volume of 

the Measure b & d

Interior Wall Dimensions

Surface Area

Marked 

Increments

on Ruler

Increment 

Volume Length Width Heightd

77.4 L

(2.73 ft3)

381 mm

(15 in)

381 mm

(15 in)

533.4 mm

(21 in)

145 161 mm2

(225 in2)

1.0 mm 

(0.03937 in) 

0.14 L

(8.5 in3)

144 L

(5.09 ft3)

508 mm

(20 in)

508 mm

(20 in)

558.8 mm

(22 in)

258 064 mm2

(400 in2)

0.25 L

(15.2 in3)

283 L

(10 ft3)

609.6 mm

(24 in)

609.6 mm

(24 in)

762 mm

(30 in)

371 612 mm2

(576 in2)

0.37 L

(22.5 in3)

Cylindrical Test Measures 

These dimensions are based on the tube having a 1/4 inch wall thickness. Other tube thicknesses may be 

used.

Actual Volume

Volume = πr2h

Interior Diameter

(Outside Diameter) Height Surface AreaArea = πr2 Increment IncrementVolume

52 L

(1.8 ft3)

292.1 mm (304.8 mm)

11.5 in (12 in)

780 mm

(30.70 in)

67 012 mm2

(103.8 in2)

1.0 mm 

(0.03937 in) 

0.06 L

(4 in3)

124 L

(4.3 ft3)

444.5 mm (457.2 mm)

17.5 in (18 in)

800 mm

(31.49 in)

155 179 mm2

(240.52 in2)

0.15 L

(9.4 in3)

279 L

(9.8 ft3)

596.9 mm (609.6 mm)

23.5 in (24 in)

1000 mm

(39.37 in)

279 829 mm2

(433.76 in2)

0.27 L

(16.4 in3)

Notes 

a. Rectangular and Square Based Dry Measures are typically constructed of 12.7 mm to 19.05 mm 

(0.5 in to 0.75 in) marine plywood. A 4.76 mm (3/16 in) transparent sidewall is useful for 

determining the level of fill, but must be reinforced or be made of thicker material if it distorts 

when the measure is filled. If the measure has a clear front, place the level gage at the back 

(inside) of the measure so that the markings are read over the top of the animal bedding. Any of 

these measures may be made without an attached bottom for ease of emptying if they are placed 

on a solid level base during filling and measurement. 

b. Other size measures may be used if calibrated and the volume equivalence of the increment of 

1.0 mm is no greater than 1/6 the MAV. Widening the base of a measure reduces the column 

height of the product and will reduce compression but the trade-off is that the larger surface area 

increases the volume so the potential for measurement errors increase. One of the benefits of the 

cylindrical design is that, in addition to eliminating the 90 degree angles of the corners where 

gaps in fill frequently occur, the surface area of a cylinder is less than an equal volume square 

measure and that results in better resolution in the volume measurements (i.e., compare the 

readability of a 24 in sq box which has a surface area of 576 in2, to the 24 in cylinder which has 

a surface area of 433 in2). The height of the test measure may be reduced, but this will limit the 

volume of the package that can be tested. 

c. If lines are marked in any test measures, they should extend around all sides of the measure if 

possible to improve readability. It is recommended that a line indicating the MAV level also be 
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marked to reduce the possibility of reading errors when the level of the product is at or near the 

MAV. 

d. If the measures are built to the dimensions shown above, the actual volume of most of the 

measures will be larger than the nominal volume so that plus errors (overfill) can be measured 

accurately.

Test Note: Nothing in this section should be construed or interpreted as prohibiting the use of test 

measures meeting these specifications, or constructed in other geometric shapes or dimensions, or 

those made of other materials to test any other products. 

3.15.2. Test Procedure 

Test Notes: 

Rounding: When a volume measurement falls between graduations on a ruler, round the value in 

the direction that favors the packer. This practice eliminates the issue of rounding from the volume 

determination and provides packagers the benefit of the doubt. The ruler graduation is 1.0 mm so 

the rounding error will be limited to 0.5 mm or less. It is good practice to circle a measurement 

that has been rounded up or make a statement to such effect so that it becomes a part of the 

inspection record. 

Safety Precautions:

This procedure does not address all of the safety issues that users need to be aware of in order to carry 

out the following tasks. Users are sometimes required to conduct test in warehouse spaces or retail 

stores where fork-trucks are in motion – care must be taken to warn others to avoid or exercise care 

around the test site. The procedure requires users to lift heavy objects including large bulky packages 

and test measures and includes the use of sharp instruments to obtain packages from shrink-wrapped 

pallets. Users may be required to climb ladders or work platforms to obtain packages. When opening 

and emptying packages, dust, and other particles may be present or escape from the packages which 

may cause eye injuries and respiratory or other health problems. Users must utilize appropriate safety 

equipment and exercise good safety practice. If safe working conditions cannot be ensured, suspend 

testing until the situation is corrected. 

1. Follow Section 2.3.1. “Define the Inspection Lot” select “Category A, Sampling Plan” in this 

inspection. Determine the Sample Size based on the size of the Inspection Lot using Category 

A. Collect the sample packages from the Inspection Lot using Section 2.3.4. “Random 

Sampling Selection.” 

Test Notes: 

(1) Place the test equipment and sample packages in a location where there is adequate lighting 

and ample space around the packages and equipment so the packages can be opened and the 

chutes and test measures used safely.

(2) If the package is not labeled with a usable volume, it is opened and the contents are poured 

directly into the test measure.
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Optional – Audit Screening by Weight

The full test procedure requires that all of the packages be opened for testing. Regardless of the 

type of bedding, the product cannot be returned to the original package. An alternative gravimetric 

auditing procedure may be used to reduce the amount of destructive testing and conserve inspection 

resources. 

Audit Procedure: After randomly selecting the sample packages from the Inspection Lot, obtain 

the gross weight for each package. Select the lightest and heaviest packages and conduct a usable 

volumetric test these two packages. If the lightest and heaviest packages pass (i.e., each contains 

at least the useable volume declared on the label), it is highly likely that the remaining packages in 

the sample will also pass. Accept these two package samples as an AUDIT TEST and move on to 

inspect other types of bedding or Inspection Lots of other types or brands of bedding. If either of 

the two packages is found to have a minus error that exceeds the Maximum Allowable Variation, 

the sample fails. No further testing is required (i.e., assuming no MAV is allowed for the sample 

size (see Appendix A, Table 2-1. “Sampling Plans for Category A”.) If either of the packages is 

found to have a minus error that does not exceed the MAV, continue to test all of the packages and 

take action based on the final results from the complete sample.

Test Note: If the gravimetric audit procedure is used, ensure the scale is placed on a solid level support,

and its accuracy has been verified to a test load that is at least 10 % more than the gross weight of the 

packages (e.g., to estimate the load, place one of the packages on the scale and then test the scale with 

a load above the package’s gross weight). See Section 2.2. “Measurement Standards and Test 

Equipment” for additional information. 

2. Select the appropriate test measure for the package size.

 Spread a tarp large enough to hold a chute and test measure. 

 Place the chute and test measure on the tarp. Verify that the test measure is level. 

3. Select a chute of appropriate capacity (see Table 3-7. “Recommended Chute Dimensions”) for 

the package size and position it on the tarp.

4. Open the packaging, uncompressing and pouring the bedding into the test measure twice.

 Open Package: Place the package in the chute and use a knife or box cutter to open and 

remove the wrapper. Spread the bedding uniformly along the length of the chute. The 

bedding is uncompressed in two steps. The first step is to loosen the clumps of bedding by 

gently pulling them apart (do not tear the fibers of cellulose bedding or “grind” any bedding 

between your hands because these practices break the material down). Spread your fingers 

and pick the material up using your hands from beneath to loosen it up. There should be 

no clumps of bedding in the chute. If any bedding has fallen out of the chute onto the tarp, 

collect it and return it to the chute. The following pictures illustrate this step of the 

procedure. The second step of the expanded volume recovery process is to pour the 

bedding into a test measure as described in Step 2.
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Figure 3-20. First Pour into the Test Measure.

 First Pour: The first pour into the test measure is only used to further un-compress the 

bedding so no measurements are taken. Hold the chute above the test measure and tilt it 

so that you pour the bedding into the center of the test measure. The bedding should be

poured slowly into the test measure in one continuous stream and not “dumped” (if it is 

“dumped” or poured too quickly some of the bedding will blow out of the measure or the 

bedding will be packed down and its volume reduced). The flow rate should be controlled 

by the tilt angle of the chute. The chute itself can be shaken but DO NOT HIT OR SHAKE 

THE TEST MEASURE. Also, do not touch the product to facilitate flow. (Do not adjust 

the flow by closing the opening of the chute as that may cause the bedding to heap up and 

then fall into the measure in clumps, which may result in impact compression). Empty the 

bedding back into the chute and spread it out evenly along its length.

Figure 3-18. Spreading Bedding Figure 3-19. Loosening the Clumps of 

Bedding Material.
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Figure 3-21. How to Hold a Chute for 

the Pour.

Figure 3-22. How to Cradle the Chute. 

Cradle the chute on one arm while 

holding it with one hand and tilting the 

cradle with the other hand. 

 Second Pour: The second pour into the test measure is used to make the volume 

determination. Hold the chute above the test measure and tilt it so that you pour the bedding 

into the center of the test measure. The bedding should be poured slowly into the test 

measure in one continuous stream and not “dumped.” The flow rate should be controlled 

by the tilt angle of the chute. The chute can be shaken but DO NOT HIT OR SHAKE THE 

TEST MEASURE. 

Test Note: Stop filling the measure if it appears that the test measure will overflow. The overflow 

product should be measured separately (use a smaller test measure of adequate size and capacity if 

one is available) and the multiple measurement volumes are added. If pouring into a square test 

measure, pour at an angle to two corners for the widest opening (see Figure 3-24. “Filling a Test 

Measure”).
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Figure 3-23. Filling a 44 L Test 

Measure.

Figure 3-24. Filling a Test 

Measure at an Angle to use 

the Larger Opening.

5. Volume Determination. 

DO NOT HAND LEVEL THE SURFACE OF THE BEDDING AS MANUAL LEVELING 

“PACKS” THE BEDDING AND REDUCES ITS VOLUME. DO NOT JAR OR SHAKE 

THE TEST MEASURE

Test Note: Before using a test measure for volume determinations, place a level of adequate 

length on top of the test measure at approximately three equal measuring points across the top. 

A permanent marking pen can be used to evenly space the marks across the top edge of the test 

measure so that it can be positioned to take the measurements. (see Figure 3-25. “Marking 

Evenly Spaced Measuring Points.”) 
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Figure 3-25. Marking Evenly Spaced Measuring 

Points across the top of the test measure.

 Place a rigid level or straight edge of adequate size on top the test measure and select a 

ruler of adequate length to reach to the lowest level of the top surface of the bedding. Start 

at the measuring points to your left or right, place the ruler against the side of the level, and 

hold it with either hand. The zero graduation is pointed down so the ruler can be lowered 

into the test measure for measurement. Lower the ruler into the test measure slowly until 

its end is at the surface level of the bedding (see Figure 3-26. “Placing the Ruler into the 

Test Measure with Zero End Down” and Figure 3-27. “Ruler Shown with Zero End at the 

Bedding Surface). 

Figure 3-26. Placing the Ruler into the 

Test Measure with Zero End Down.

Figure 3-27. Ruler Shown with the Zero 

End at the Bedding Surface.

 Determine the depth of each measurement point from the surface of the bedding to the 

bottom edge of the straight edge and record the value in the appropriate space on the 

worksheet. Take a minimum of nine measurements (at least 9 for cylindrical measures)
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across the top of the test measure in a grid pattern. Read the graduations on the ruler from 

a position that minimizes errors caused by parallax.

Table 3-9.

Illustrations of Depth Determinations with Cylindrical Test Measures

The picture on the left (Illustration 1) shows how 

to read the depth from the bottom of the 

straightedge (top edge of measure) down to the to 

bedding in a 44 L test measure from a position that 

reduces parallax. The graphic below (Illustration

2) illustrates the actual worksheet with the 

headspace procedure on the 44 L cylinder test 

measure (its internal radius is 151.77515 mm and 

its height is 610 mm). The bedding was poured 

into the test measure but not leveled. Then 

nine measurements were made at the locations 

shown on the grid to determine the depth of the 

product from the top edge of the measure. The 

average of the nine values was 479.88 mm which 

was subtracted from the height of the test measure 

to obtain 130.12 mm for the average height of the 

column of bedding in the measure. 

The volume was calculated using: 

Volume in liters = (πr2

h) 3.14159265 (Pi) ×

23035.69 mm × 130.12 mm = 9.41 L*

*After the calculation was completed the result 

was divided by 1 000 000 to obtain the volume in 

liters.

Illustration 1. Reading the Depth of the 

Container. This photo illustrates how to read 

the depth of container.

Illustration 2. Illustration of Worksheet.

439 430 419

475 492 462

542 528 532
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Table 3-9.

Illustrations of Depth Determinations with Cylindrical Test Measures

Illustration 3. Using the headspace measurement on a 279 L test measure. The ruler is read 

from the bottom edge of a straight edge or level 

from a position that reduces parallax.

Illustration 4. Illustrating how the ruler is 

placed on the bedding with the headspace 

method. The ruler is read from the bottom edge 

of a straight edge or level from a position that 

reduces parallax.
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Table 3-10.

Illustrations of Depth Determinations with Square Test Measures

Illustration 1. Depth Determination. Illustration 2. Measurement Grid 

for Headspace Measurement 

Procedure.

The picture on the left (Illustration 1. Depth Determination) shows how to read the depth from the bottom 

of the straightedge (top edge of measure) down to the bedding in a 283 L square test measure from a 

position that reduces parallax. The graphic on the right (Illustration 2. Measurement Grid for Headspace 

Measurement Procedure) illustrates the actual worksheet with the headspace procedure on the square 

test measure (its internal dimensions are 609.6 mm × 609.6 mm × 762 mm (24 in × 24 in × 30 in). The 

bedding was poured into the test measure but not leveled. Then nine measurements were made at the 

locations shown on the grid to determine the depth of the product from the top edge of the measure. The 

average of the nine values was 78.77 mm that was subtracted from the height of the test measure to 

obtain 683.23 mm for the average height of the column of bedding in the measure. 

The volume was calculated using:

Volume in liters = lwh 609.6 mm × 609.6 mm × 683.23 mm = 253.89 L*

*After the calculation was completed, the result was divided by 1 000 000 to obtain the volume in 

liters.

115 43 46

77 51 95

138 46 98
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Table 3-10.

Illustrations of Depth Determinations with Square Test Measures

Illustration 3. Using the headspace 

measurement on 56.6 L (2 cu ft) test 

measure. The ruler is read from the 

bottom edge of a straight edge or 

level from a position that reduces 

parallax.

Illustration 4. Showing how the ruler is 

placed on the bedding with the headspace 

method. The ruler is read from the bottom 

edge of a straight edge or level from a 

position that reduces parallax.

6. Using the Worksheet for Volume Calculation 

 Enter the sample number of the package on the worksheet along with its labeled usable 

volume. 

 Test Measure Information

• For a cylindrical test measure, enter its interior height and radius in the spaces labeled 

A and B.

• For a square or rectangular test measure enter its interior height and the area of its base 

(i.e., length × width) in spaces labeled A and B.

 Sum the measurements in the grid, divide the value by the number of measurements 

(i.e., 9), and enter this value in the space labeled C, Average Depth. 
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 Calculate the Average Height of the Bedding (subtract C [Average Depth] from A [Interior 

Height of Test Measure]) and enter this value in the space labeled D. 

 Calculate the Volume of Bedding in the Package:

• For a cylindrical test measure, the formula (Volume in Liters = πr2

h) is shown on line

E on the worksheet. It is:

Volume (Liters) = 3.14159265 × r

2 (B2

) × Average Height (D) ÷ 1 000 000.

Enter the package volume in the space provided for this value in line E.

• For a square or rectangular test measure the formula (Volume in Liters = LWH) is 

shown in line E on the worksheet. It is:

Volume (Liters) = B (Area of Test Measure Base) × D (Average Height) ÷ 1 000 000.

Enter the package volume in the space provided for this value in line E.

 Calculate the Package Error using the following formula: 

• Package Error = Labeled Usable Volume (Liters) − E Package Volume (Liters) 

Package Error (Liters) = Labeled Expanded Volume – Package Volume 

 Transfer the individual package errors (verify whether they are positive or negative) to the 

“Standard Package Report – Animal Bedding” in Appendix D. Fill in the required header 

information. For Box 7, “Number of Unreasonable Package Errors Allowed for Sample 

Size”, use Appendix A Table 2-1. “Sampling Plans for Category A”, “Column 4.”, Based 

on the sample size, determine how many packages may have minus package errors that 

exceed the MAV (i.e., unreasonable package error). 

THEN:

 Calculate the Total Error (Enter in Box 8. “Total Error”). 

(Amended 2016)

3.15.3. Evaluation of the Test Results and Determination of Pass or Fail

1. Determine if any of the minus package errors exceeds the MAV. Apply a MAV value of 5 % 

(0.05 × labeled expanded volume) to single measurement volume determinations. If none of 

the minus package errors exceeds the MAV, go to Step 3. If any of the minus package errors 

exceed the MAV, enter the number of packages in Box 9 “Number of Unreasonable Minus 

Errors”. Go to Box 10 “Is Box 9 Greater than Box 7?” and determine if the value exceeds the 

number in Box 7 “Number of Unreasonable Package Errors Allowed for Sample Size”. If the 

number of packages with unreasonable errors exceeds the number permitted in Box 7 “Number 

of Unreasonable Package Errors Allowed for Sample Size,” the sample fails. Go to Box 17 

“Disposition of the Inspection Lot” and reject the Inspection Lot.

2. Calculate the Average Error for the sample by dividing Box 8 “Total Error,” by Box 6 “Sample 

Size” and enter the value in Box 11 “Calculate Average Error,” then go Box 12 “Does Box 11 
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equal Zero or Plus?” If the Average Error is zero or a positive number the sample passes, go 

to Box 17 “Disposition of the Inspection Lot” and approve the inspection lot. If the Average 

Error is a negative value go to Step 3. 

3. Calculate the Sample Standard Deviation and enter in Box 13. “Compute Sample Standard 

Deviation.” To obtain the Sample Correction Factor for the sample size use Appendix A, Table 

2-1. “Sampling Plans for Category A,” Column 3 “Sample Correction Factor’ and enter that in 

Box 14 “Sample Correction Factor.” Then calculate the Sample Error Limit by multiplying 

Box 13 “Compute Sample Standard Deviation” and Box 14 “Sample Correction Factor.” Enter 

the value in Box 15 “Compute Sample Error Limit.”

 Disregarding the signs, determine if the minus in Box 11 “Calculate Average Error” is 

larger than the value in Box 15 “Compute Sample Error Limit.” 

 If yes, the sample fails, go to Box 17 “Disposition of Inspection” and reject the Inspection 

Lot. 

 If no, the sample passes, go to Box 17 “Disposition of Inspection” and approve the 

Inspection Lot 

4. Prepare a comprehensive report of the test results and enforcement action taken and present the 

information to the party responsible for the product. 

(Amended 2016)