Marketing and

Regulatory

Programs

Agricultural

Marketing 

Service

Specialty 

Crops

Program

Specialty

Crops

Inspection

Division

United States Standards

for Determination of

Fill Weights

Effective May 29, 1973

Reprinted October 18, 2019
This is a reprint of the United States Standards for Determination of Fill Weights 

which have been in effect since May 29, 1973 and were updated to modify the format

and update obsolete contact information. 

Voluntary U.S. grade standards are issued under the authority of the Agricultural 

Marketing Act of 1946, which provides for the development of official U.S. grades to 

designate different levels of quality. These grade standards are available for use by 

producers, suppliers, buyers, and consumers. As in the case of other standards for 

grades of fresh and processed fruits, vegetables, and specialty crops these 

standards are designed to facilitate orderly marketing by providing a convenient 

basis for buying and selling, for establishing quality control programs, and for 

determining loan values. 

The U.S. grade standards and inspection instructions for all fresh and processed fruits,

vegetables, and specialty crops are available on the internet and upon request at the 

address below. These documents provide detailed interpretations of the grade standards 

and provide step-by-step procedures for grading the product. 

Grade standards are issued by the U.S. Department of Agriculture (USDA) after careful 

consideration of all data and views submitted during rulemaking. The Department 

welcomes suggestions for improving the standards in future revisions. Comments may be 

submitted to, and copies of standards and inspection instructions obtained from: 

Director, Specialty Crops Inspection Division

Specialty Crops Program, 

USDA, Agricultural Marketing Service

1400 Independence Avenue, SW, STOP 0240 

Washington, D.C. 20250

Authority: 7 U.S.C. 1621-1627. 

Note: Compliance with the provisions of these standards shall not excuse failure to 

comply with the provisions of the Federal Food, Drug, and Cosmetic Act, or 

with applicable State laws and regulations.

Non-Discrimination Policy: In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and 

policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from 

discriminating based on race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, 

marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil 

rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing 

deadlines vary by program or incident.

Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American 

Sign Language, etc.) should contact the responsible Agency or USDA's TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA 

through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English.

To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at How to File a 

Program Discrimination Complaint and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information 

requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: 

U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-

9410; (2) fax: (202) 690-7442; or (3) email: program.intake@usda.gov.

USDA is an equal opportunity provider, employer, and lender.
United States Standards for Determination of Fill Weights (May 29, 1973)

1

United States Standards for Determination of Fill Weights

______________________________________________________________________

Section Page No.

General........................................................................................................................... 2

§52.221 Purpose.................................................................................................... 2

§52.222 Explanation............................................................................................... 2

§52.223 Options..................................................................................................... 2

§52.224 Type of specification and applicable limits. .............................................. 2

Procedure ...................................................................................................................... 3

§52.225 Preparation of forms................................................................................. 3

§52.226 Posting control charts............................................................................... 3

§52.227 Determination of tare of containers. ......................................................... 3

§52.228 Sampling. ................................................................................................. 4

§52.229 Measurements.......................................................................................... 4

§52.230 Calculations and recording data............................................................... 5

Interpretations ............................................................................................................... 6

§52.231 Interpretation of plotted values with respect to limits................................ 6

Optional Fill Weight Procedure for Small Lots ........................................................... 6

§52.232 Optional fill weight procedure for small lots. ............................................. 6

Attachments .................................................................................................................. 8

Attachment 1—Sample XX and R data sheets.................................................................. 8

Attachment 2—Sample control chart............................................................................... 9
United States Standards for Determination of Fill Weights (May 29, 1973)

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General

§52.221 Purpose.

These proposed standards supplement the proposed U.S. Standards for Inspection by 

Variables so as to adapt them to the determination of fill of container, based on fill 

weights, for canned fruits vegetables, and related products.

§52.222 Explanation.

(a) The variables inspection standards may be used, where applicable, by any 

food processor for quality control purposes. Certification by the U.S. 

Department of Agriculture (USDA) of fill weights based on these standards, 

however, is applicable only under on-line inspection when a USDA inspector is 

present at time of packing and maintains appropriate records of the filling 

process.

(b) The procedure for determination and certification of fill of container, based on

drained weights, may be used in the case of lot inspection as well as in-line

inspection. This procedure, where applicable, is outlined in the U.S. standards 

for the respective products.

§52.223 Options.

The options of the median or conventional average may be used for determining

compliance of fill weights with a specified minimum average fill weight.

§52.224 Type of specification and applicable limits.

(a) For the determination of fill weights, a low-sided specification applies.

(b) The specification limits, and values for such limits, are specified in those U.S. 

Standards for Grades of canned fruits, vegetables, and related products which 

incorporate the fill weight procedure. Suggested specification limits, and the 

values for such limits, for those products for which fill weights have been 

established—but are not yet incorporated in the USDA grade standards—may be 

obtained as supplements to these standards upon request to:

Director, Specialty Crops Inspection Division

Specialty Crops Program, 

USDA, Agricultural Marketing Service

1400 Independence Avenue, SW, STOP 0240 

Washington, D.C. 20250

(c) All of these limits, whether stated in the USDA grade standards or supplements

hereof, are to be applied in accordance with the proposed U.S. Standards for

Inspection by Variables.
United States Standards for Determination of Fill Weights (May 29, 1973)

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Procedure

§52.225 Preparation of forms.

(a) Prepare the data sheet and control charts prior to the start of a processing 

period. Draw lines representing the XX’min, LRLxx, and LRL values applicable for 

the product, container size, and style on the appropriate linear segment of the XX

chart in such a manner as to be clearly visible when posted in the plant. Lines 

representing LWLxx and LWL may be drawn on the chart at the option of the user; 

however, all the values representing each limit (XX’min, LWLxx, LRLxx, LWL and 

LRL) are placed on the XX chart adjacent to the appropriate limit and identified (in 

brief form) as XX’, WLxx, RLxx, WL, or RL accordingly).

(b) When the R chart is used, it is desirable to place it on lower portion of the control

chart, using the bottom as zero, which is the lower limit for R.

(c) Space the limits for RR’ and Rmax on the appropriate linear segment above the zero

line. The upper portion of the control chart is then used for the XX chart.

(d) Attachment 1 is an example of an XX and R data chart. Attachment 2 is an 

example of a control chart which combines the XX chart and the R chart.

However, use of the R chart is not required. The XX chart illustrates the use of the 

median option as prescribed in the proposed U.S. Standards for Inspection by 

Variables. The dots plotted on the XX chart represent the X values for the 

subgroup. The encircled dot represents the median of each subgroup. For 

easier identification the circle should be in a different color than the dots.

§52.226 Posting control charts.

It is desirable to post the control charts in such a place in the plant as to be clearly

visible to the filler operator as well as other responsible plant personnel. The control 

charts serve as an aid to responsible plant personnel in controlling the filling process.

§52.227 Determination of tare of containers.

(a) General. Variations in the weight between individual empty containers (tare)

must be taken into consideration when determining fill weights. These variations

may be accounted for by procedure 1 or procedure 2 of this section.

(b) Procedure 1. Determine tare weights of each container size at least twice a

week. In addition, determine tare weights whenever it is suspected that the 

present tare weight is no longer applicable. Some of the more common reasons 

for checking tare weights are changes in supply of containers, thickness of tin

plate, and type of container.
United States Standards for Determination of Fill Weights (May 29, 1973)

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(1) The number of empty containers taken at random from a given lot of 

containers to determine the average tare weight is as follows:

For containers equivalent to:

No. 2-1/2 containers and smaller----not less than 10 empty containers.

Larger than No. 2-1/2-------------------not less than 15 empty containers.

(c) Procedure 2. Preweigh a container (preferably stainless steel or other 

noncorrosive material) of suitable capacity and use this container as the standard 

tare. Drain the contents of the filled container as prescribed in §52.229 and 

transfer drained fruit or vegetable ingredient to the preweighed tare.

§52.228 Sampling.

(a) Subgroup size. Unless otherwise specified, the subgroup size shall be five

sample units.

(1) The control chart values, except for XX’min, will always be based on the 

specified subgroup size. When a subgroup size other than that specified 

is used, the values for the applicable limits must be changed accordingly.

(b) Time and point of sampling. The subgroups are drawn at a point in the process

where no further change in the fill weight of the fruit or vegetable ingredient can

occur.

(c) Sampling frequency. Unless otherwise specified, the sampling frequency for all

canned fruits, vegetables, and related products, for which fill weights have been

established shall be approximately every 45 minutes.

(1) The sampling frequency should be arranged to obtain subgroups at 

varying intervals and drawn in such a manner that the filler operators will 

not know when a subgroup will be drawn or which containers will be in the 

subgroup. This is important so that a nonbiased sample will be selected 

which will reflect the normal filling process.

§52.229 Measurements.

(a) Immediately after the subgroup has been drawn, invert each container on the 

hand or sieve and allow the product to drain until free from liquid, but in no case 

less than 10 seconds. In this step, do not remove the product from the container 

when procedure 1 as prescribed in §52.227 is used. The sample units are then 

weighed and the net weight of the fruit or vegetable ingredient (total weight minus 

tare weight) for each sample unit is recorded on the XX and R data sheet.

(b) In the case of procedure 1 if it is suspected that the weight of individual empty

containers deviate from the average tare weight to cause an individual 
United States Standards for Determination of Fill Weights (May 29, 1973)

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measurement to fall slightly below (or slightly above) LRL, the following 

procedure may be used:

(1) After the X value has been obtained as previously described, empty the 

contents of the suspected container and wipe it clean and dry.

(2) Weigh the suspected dry container. The amount of deviation is the 

difference between the weight of the individual container and the average 

tare weight.

(3) Adjust the suspected X value by the amount of deviation thus found.

(c) When adjustments for tare weight are made for individual measurements that fall

slightly below LRL, adjustments must also be made for individual measurements

that are slightly above LRL.

§52.230 Calculations and recording data.

(a) Immediately after the measurements have been obtained, the required 

calculations are made. All values are recorded to the nearest 0.1, rounding the 

values as follows:

(1) Drop any values less 0.050—

EXAMPLE:

XX calculated to be 18.743

Record XX as 18.7

(2) Increase any values to the next 0.1 when they are 0.050 or more—

EXAMPLE:

XX calculated to be 10.650

Record XX as 10.7

(b) After the required calculations are made and recorded, the appropriate values 

are plotted in accordance with the proposed U.S. Standards for Inspection by

Variables.
United States Standards for Determination of Fill Weights (May 29, 1973)

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Interpretations

§52.231 Interpretation of plotted values with respect to limits.

(a) Warning limits. The values representing LWL and LWLxx are provided for the

processor’s benefit to use for control purposes. These limits are not to be 

confused with reject limits.

(1) An X value that falls between LWL and LRL or XX value that falls between 

LWLxx and LRLxx may be expected occasionally, even when the process is 

still meeting requirements. This is the point, however, at which corrective 

action in the filling procedure may be taken.

(b) Code Segregation. The acceptance criteria specified in the proposed U.S.

Standards for Inspection by Variables requires all X values to be equal to or 

above LRL for a low-sided specification and all Mi or XX values to be equal to or 

above LRLxx.

(1) When an X, Mi, or XX value(s) causes a code or distinctive mark to be 

rejected, the code or mark for the remainder of the shift may be changed 

to provide a chance for subsequent production for that shift to pass.

(c) Sampling Allowances. The sampling allowance code for each can size and style 

is specified in the grade standards which incorporate fill weights and the 

supplement to these standards for the applicable product. To determine the 

sampling allowance, first obtain the letter code for the appropriate container size 

and style from the table containing the fill weight values. Locate the line 

represented by this code on the sampling allowance chart accompanying the 

U.S. Standards for Inspection by Variables. This line represents the sampling

allowance for the various sample sizes. Deduct this value from XX’min. Do not add 

this value to XX or MMi.

(1) The sampling allowance does not apply to a sample size of less than 10 

sample units.

Optional Fill Weight Procedure for Small Lots

§52.232 Optional fill weight procedure for small lots.

(a) For lots consisting of 100 cases or less which require 4 hours or more to pack, 

the following minimum sampling rate and acceptance criteria may be used in lieu 

of the requirements and procedures outlined in the U.S. Standards for Inspection 

by Variables. The conventional average option must be used for this procedure. 

Do not use the sample median (MMi).
United States Standards for Determination of Fill Weights (May 29, 1973)

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(b) Draw a minimum of 15 sample units, one or two at a time throughout the entire

production of the lot. The sampling intervals shall be such that the total sample

will be representative of the lot.

(c) Accept the lot if:

(1) No X value is less than LRL.

(2) XX is equal to or greater than XX’min adjusted; and

(3) The condition under paragraph (d) (3) of this section does not exist.

(d) Reject the lot if:

(1) XX is less than XX’min adjusted; or

(2) One or more X values are less than LRL; or

(3) All X values are less than XX’min.
United States Standards for Determination of Fill Weights (May 29, 1973)

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Attachments

Attachment 1—Sample XX and R data sheets.
United States Standards for Determination of Fill Weights (May 29, 1973)

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Attachment 2—Sample control chart.