ASTM D5639/D5639M-20

Standard Practice for Selection of Corrugated Fiberboard Materials and Box Construction Based on Performance Requirements

SIGNIFICANCE AND USE
4.1 This practice assists users in selecting appropriate performance characteristics of corrugated fiberboard or box construction, or both, commensurate with their user’s needs for packing and distribution of goods. This practice describes several attributes of fiberboard and boxes which relate to various hazards encountered in distribution and describes test parameters which may be specified by the user to ensure sufficient strength in the box for containment, storage, handling, transport and protection of contents.  
4.2 The user should specify only those attributes and related tests which are required for performance to the users satisfaction including their operations and distribution cycle(s). When using the carriers’packaging rules as the major basis for developing specifications, the reason for the rule and its function and importance should be understood. As previously stated, rules and regulations may be exceeded and should be when the minimum specifications are inadequate for the full effects of the distribution cycle, etc.. If the user decides to employ box compression strength or a rough handling performance protocol as the overriding specification, it should be noted that all minimum standards required by various organizations shall also be met or surpassed if using the related certificate. These minimum standards can be stated in the box drawing so as to ensure adherence to rules and regulations. If a Box Manufacturer’s Certificate (BMC) is printed on the box, then the ECT or Mullen Burst/Basis Weight values shall meet or exceed the minimum requirements for size and weight of the packaged product.  
4.3 See Appendix X7 for several examples of specification determinations.
SCOPE
1.1 This practice provides information on corrugated fiberboard for the prospective user who wants guidance in selecting attributes of materials and box construction based on performance requirements. These attributes should be part of specifications which establish levels of the qualities a shipping container shall have achieved in order to be acceptable to the purchaser or user. The attributes and qualities should be testable, using standard methods that are recognized by both the buyer and seller. This practice will assist users in developing specifications for corrugated containers through an analysis of performance requirements and subsequent relationships to fiberboard materials and box construction attributes. This practice is meant to complement the box buyer–box manufacturer relationship by having the buyer (user) better understand, discuss, and negotiate needed elements of box design and specification. The full box design process is complex, and it is beyond the scope of this standard.  
1.2 The attributes and their levels should be based on the intended use of the box, including the handling and environment it will encounter. Many packaging rules include detailed descriptions of the materials that may be used and style, closure, or other construction details of allowed shipping containers. These rules are presented as minimum requirements; they may be exceeded for functional reasons, but there is no regulatory reason to do so. Rail and motor freight classifications applicable for surface common carrier transportation have established minimum requirements for certain attributes of corrugated packaging. These may or may not be appropriate for application in the complete distribution system, as they encompass only containerboard or combined corrugated board — not finished boxes — and are not intended to provide for the distribution and storage system beyond the transportation segment.  
1.2.1 The attribute levels contained herein are based on U.S. practice and specifications. Some attributes such as flute dimensions and basis weights may be defined differently in other countries.  
1.3 There are four common methods used for specifying boxes.  
1.3.1 A common approach is to examine boxes cur...

General Information

• Status: Published
• Publication Date: 30-Sep-2020
• ICS: 55.160 - Cases. Boxes. Crates
• Technical Committee: D10 - Packaging
• Drafting Committee: D10.27 - Fiberboard Shipping Containers, Containerboard and Related Structures and Materials

Relations

• Refers: ASTM D4169-23 - Standard Practice for Performance Testing of Shipping Containers and Systems
• Effective Date: 01-Dec-2023
• Refers: ASTM D4169-23e1 - Standard Practice for Performance Testing of Shipping Containers and Systems
• Effective Date: 01-Dec-2023
• Refers: ASTM D5276-19(2023) - Standard Test Method for Drop Test of Loaded Containers by Free Fall
• Effective Date: 01-Oct-2023
• Refers: ASTM D5276-98(2017) - Standard Test Method for Drop Test of Loaded Containers by Free Fall
• Effective Date: 01-Sep-2017
• Refers: ASTM D7386-16 - Standard Practice for Performance Testing of Packages for Single Parcel Delivery Systems
• Effective Date: 01-Apr-2016
• Refers: ASTM D4727/D4727M-15 - Standard Specification for Corrugated and Solid Fiberboard Sheet Stock (Container Grade) and Cut Shapes
• Effective Date: 01-Oct-2015
• Refers: ASTM D1968-15 - Standard Terminology Relating to Paper and Paper Products
• Effective Date: 01-Oct-2015
• Refers: ASTM D4727/D4727M-15e1 - Standard Specification for Corrugated and Solid Fiberboard Sheet Stock (Container Grade) and Cut Shapes
• Effective Date: 01-Oct-2015
• Refers: ASTM D4169-14 - Standard Practice for Performance Testing of Shipping Containers and Systems
• Effective Date: 01-Nov-2014
• Refers: ASTM D2658-04(2013) - Standard Test Method for Determining Interior Dimensions of Fiberboard Boxes (Box Gage Method)
• Effective Date: 01-Oct-2013
• Refers: ASTM D685-12 - Standard Practice for Conditioning Paper and Paper Products for Testing
• Effective Date: 01-Nov-2012
• Refers: ASTM D5168-12 - Standard Practice for Fabrication and Closure of Triple-Wall Corrugated Fiberboard Containers
• Effective Date: 01-May-2012
• Refers: ASTM D7386-12 - Standard Practice for Performance Testing of Packages for Single Parcel Delivery Systems
• Effective Date: 01-Apr-2012
• Refers: ASTM D5118/D5118M-12 - Standard Practice for Fabrication of Fiberboard Shipping Boxes
• Effective Date: 01-Apr-2012
• Refers: ASTM D4727/D4727M-12 - Standard Specification for Corrugated and Solid Fiberboard Sheet Stock (Container Grade) and Cut Shapes
• Effective Date: 01-Apr-2012

Overview

ASTM D5639/D5639M-20, titled "Standard Practice for Selection of Corrugated Fiberboard Materials and Box Construction Based on Performance Requirements," is a comprehensive guideline developed by ASTM International. This standard assists packaging professionals, manufacturers, and buyers in selecting suitable corrugated fiberboard materials and box constructions to meet performance requirements for the packing, storage, handling, and distribution of goods. It promotes the development of clear, testable specifications based on intended use and environmental hazards encountered during distribution cycles.

Key Topics

• Performance-Based Selection: The standard emphasizes identifying attributes (such as strength, rigidity, and resistance to puncture) that are testable and relevant to the specific use case of the corrugated box.
• Methods of Specification: Four main approaches are described: replicating existing box designs, estimating compression strength, focusing on burst strength, or using rough handling test protocols.
• Material Attributes:
  • Flute Structure and Construction: Selection from singlewall, doublewall, or triplewall boards, considering common flute types (A, B, C, E) based on structural and performance requirements.
  • Burst Strength: Evaluation of tensile and rupture strength for resistance to rough handling.
  • Edgewise Crush Resistance (ECT): Correlated with compression strength, important for stacked boxes.
  • Flat Crush and Stiffness: Assessed for overall board rigidity and protective properties.
  • Puncture Resistance: Relevant for rough handling and protection against sharp impacts.
• Box Construction Details: Recommendations on style selection (e.g., Regular Slotted Container) and the importance of consistent board caliper and manufacturing quality.
• Regulatory Compliance: Guidance to ensure that all applicable minimum standards and carrier rules are met, especially in relation to the Box Manufacturer’s Certificate (BMC) and federal transport regulations for hazardous materials.

Applications

ASTM D5639/D5639M-20 provides valuable tools for:

• Packaging Design and Procurement: Enables end-users to articulate precise box performance needs, facilitating communication and negotiation with box manufacturers.
• Quality Assurance: Specifies methods for verifying material and box performance, such as edge crush testing, drop testing, and compression strength testing, using recognized ASTM and TAPPI standards.
• Distribution and Logistics: Helps companies select packaging optimized for complex supply chains, different modes of transport (road, rail, parcel delivery), and varying environmental conditions.
• Regulatory Adherence: Supports compliance with industry and government regulations for fiberboard packaging, including minimum values for burst strength and edge crush resistance.
• Cost Optimization: Encourages performance-based specifications rather than strictly material-based ones, potentially reducing costs by sourcing from multiple suppliers while maintaining quality requirements.

Related Standards

Users of ASTM D5639/D5639M-20 are encouraged to consult the following references for complementary information and testing protocols:

• ASTM D642: Compressive Resistance Testing of Shipping Containers
• ASTM D5118/D5118M: Fabrication of Fiberboard Shipping Boxes
• ASTM D4169: Performance Testing of Shipping Containers and Systems
• ASTM D5276: Drop Test of Loaded Containers
• TAPPI Test Methods: Including T 411 (thickness), T 803 (puncture), T 810 (burst), T 811 (edgewise crush), T 825 (flat crush)
• Fibre Box Handbook: Industry resource for material and construction properties
• Code of Federal Regulations Title 49: US regulations for packaging hazardous materials

By following ASTM D5639/D5639M-20, packaging professionals can ensure robust, compliant, and cost-effective corrugated box solutions that address performance needs across diverse industries. This standard is widely recognized as a key resource for the development of high-quality, reliable shipping containers in global supply chains.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D5639/D5639M − 20
Standard Practice for
Selection of Corrugated Fiberboard Materials and Box
Construction Based on Performance Requirements
This standard is issued under the fixed designation D5639/D5639M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.2.1 TheattributelevelscontainedhereinarebasedonU.S.
practice and specifications. Some attributes such as flute
1.1 This practice provides information on corrugated fiber-
dimensions and basis weights may be defined differently in
boardfortheprospectiveuserwhowantsguidanceinselecting
other countries.
attributes of materials and box construction based on perfor-
mance requirements. These attributes should be part of speci-
1.3 There are four common methods used for specifying
fications which establish levels of the qualities a shipping
boxes.
container shall have achieved in order to be acceptable to the
1.3.1 Acommon approach is to examine boxes currently in
purchaser or user. The attributes and qualities should be
use for the specific application and to make a similar or
testable, using standard methods that are recognized by both
modified version of that box, given that it has a proven
the buyer and seller. This practice will assist users in develop-
performance record. This method, while quite efficient, and
ingspecificationsforcorrugatedcontainersthroughananalysis
fast, does not lead to box optimization based on characteriza-
of performance requirements and subsequent relationships to
tion by end use. This method can lead to overdesign.
fiberboard materials and box construction attributes. This
1.3.2 A second common approach is to estimate the com-
practice is meant to complement the box buyer–box manufac-
pression strength necessary for a box at the bottom of a stack
turer relationship by having the buyer (user) better understand,
ofboxestototallysupporttheanticipatedload.Asafetyfactor,
discuss, and negotiate needed elements of box design and
F, is calculated from the expected environmental hazards that
specification. The full box design process is complex, and it is
are anticipated in storage and shipping.Aminimum initial box
beyond the scope of this standard.
compression, as measured byTest Method D642 is determined
1.2 The attributes and their levels should be based on the
using the weight on the bottom box and the F factor, see 8.3.
intended use of the box, including the handling and environ-
Then engineering principles are used to select material com-
ment it will encounter. Many packaging rules include detailed
binationsbasedonmaterialcharacteristicssuchascaliper,edge
descriptions of the materials that may be used and style,
crush value, and flat crush to meet that requirement.
closure, or other construction details of allowed shipping
1.3.3 The third approach may be used when the box
containers. These rules are presented as minimum require-
application has product support sufficient to meet anticipated
ments; they may be exceeded for functional reasons, but there
compression requirements, therefore the board structural re-
is no regulatory reason to do so. Rail and motor freight
quirements are focused on protection and containment. Mullen
classifications applicable for surface common carrier transpor-
burst values can be one of these measures for this category of
tation have established minimum requirements for certain
box if the user has determined that a minimum burst value is
attributes of corrugated packaging. These may or may not be
the main metric required in their distribution system. In this
appropriateforapplicationinthecompletedistributionsystem,
case, total weight per box allowable per carrier rules may be
as they encompass only containerboard or combined corru-
higher than would be expected based on expected predicted
gated board — not finished boxes — and are not intended to
compression strength, safety factor, and board combination
provide for the distribution and storage system beyond the
used. See 7.2 – 7.2.2.2 and 8.2.1.
transportation segment.
1.3.4 The fourth approach may be used when the box is
intended for single parcel shipment of high value or hazardous
materials, where there can be a compression requirement but
This practice is under the jurisdiction ofASTM Committee D10 on Packaging
and is the direct responsibility of Subcommittee D10.27 on Fiberboard Shipping mostoftentheperformanceattributesrequiredaretoughnessas
Containers, Containerboard and Related Structures and Materials.
measured by drop and impact resistance, see 8.2. A means of
Current edition approved Oct. 1, 2020. Published December 2020. Originally
gaining confidence that a box in this category will function
approved in 1994. Last previous edition approved in 2015 as D5639/
D5639M–11(2015). DOI: 10.1520/D5639_D5639M-20. properly in its intended distribution environment is to test the
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5639/D5639M − 20
box using some sort of rough handling performance protocol D2658Test Method for Determining Dimensions of Fiber-
such as Practice D4169 or ISTA 3 Series: General Simulation board Boxes
Performance Tests. D4169Practice for Performance Testing of Shipping Con-
1.3.5 Using material specifications to define a box does not tainers and Systems
guarantee the box will be well made. For example, the best D4727/D4727MSpecification for Corrugated and Solid Fi-
possible material could be used for making a box, but if the berboard Sheet Stock (Container Grade) and Cut Shapes
scorelinesaretoodeeportooshallow,orifthemanufacturer’s D5118/D5118MPracticeforFabricationofFiberboardShip-
joint is not secured correctly, the box will fail in distribution. ping Boxes
All proposed constructions and designs should be vetted by D5168Practice for Fabrication and Closure of Triple-Wall
means of a process of samples, testing, prototype packing and Corrugated Fiberboard Containers
shipping. Only once a construction has been proven to work D5276Test Method for Drop Test of Loaded Containers by
across a range of anticipated end use conditions should it be Free Fall
approved for normal production. D7386Practice for Performance Testing of Packages for
Single Parcel Delivery Systems
1.4 Corrugated containers for packaging of hazardous ma-
E122PracticeforCalculatingSampleSizetoEstimate,With
terials for transportation shall comply with federal regulations
Specified Precision, the Average for a Characteristic of a
administered by the U.S. Department of Transportation (Code
Lot or Process
of Federal Regulations, Title49).
2.2 TAPPI Methods:
1.5 Lists and Descriptions of Performance and Material
T411 Thickness of Paper, Paperboard, and Combined
Characteristics and Related Test Procedures—For further in-
Board
formation on the development of performance-based 4
T803Puncture Test of Corrugated Fiberboard
specifications,pleaserefertothesectionsonSpecificationsand
T809Flat Crush Test of Corrugating Medium (CMT Test)
Test Procedures of the Fibre Box Handbook. 4
T810Burst Test of Corrugated Fiberboard
T811Edgewise Crush Test of Corrugated Fiberboard
1.6 The values stated in both SI and inch-pound units are to
be regarded separately as standard. Within the text, the T 825 Flat Crush Test of Corrugated Fiberboard-Fixed
Platen Method
inch-pound units are shown in brackets. The values stated in
each system are not exact equivalents; therefore, each system T836Bending Stiffness, Four Point Method
T839Edgewise Compressive Strength of Corrugated Fiber-
shall be used independently of the other.
board Using the Clamp Method (Short Column Test)
1.7 This standard does not purport to address all of the
2.3 Government Documents:
safety concerns, if any, associated with its use. It is the
CFR49Code of Federal Regulations, Title 49 §178.516 –
responsibility of the user of this standard to establish appro-
Standards for Fiberboard Boxes
priate safety, health, and environmental practices and deter-
2.4 Carrier Rules:
mine the applicability of regulatory limitations prior to use.
National Motor Freight ClassificationItem 222
1.8 This international standard was developed in accor-
Uniform Freight ClassificationRule 41
dance with internationally recognized principles on standard-
2.5 Other Publications:
ization established in the Decision on Principles for the
ISTATesting Guidelines, Testing Procedures
Development of International Standards, Guides and Recom-
Fibre BoxHandbook
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
3. Terminology
2. Referenced Documents 3.1 Definitions—For general definitions of packaging and
2 distribution environments, see Terminology D996. For paper
2.1 ASTM Standards:
and combined board related terms see Terminology D1968.
D585Practice for Sampling and Accepting a Single Lot of
Paper, Paperboard, Fiberboard, and Related Product
4. Significance and Use
(Withdrawn 2010)
4.1 This practice assists users in selecting appropriate per-
D642Test Method for Determining Compressive Resistance
formance characteristics of corrugated fiberboard or box
of Shipping Containers, Components, and Unit Loads
D685Practice for Conditioning Paper and Paper Products
for Testing Available from TechnicalAssociation of the Pulp and Paper Industry (TAPPI),
15 Technology Parkway South, Norcross, GA 30092, http://www.tappi.org.
D996Terminology of Packaging and Distribution Environ-
AvailablefromU.S.GovernmentPrintingOfficeSuperintendentofDocuments,
ments
732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
D1968Terminology Relating to Paper and Paper Products
www.access.gpo.gov.
AvailablefromtheNationalMotorFreightTrafficAssociation(NMFTA),1001
N Fairfax St, Suite 600, Alexandria, VA 22314-1748.
2 7
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from National Railroad Freight Committee,Tariff Publishing Officer,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM 151 Ellis Street, NE, Suite 200, Atlanta, GA 30335.
Standards volume information, refer to the standard’s Document Summary page on Available from ISTA Distributing Confidence, Worldwide TM 1400 Abbott
the ASTM website. Road, Suite 160 East Lansing, MI 48823; www.ista.org
3 9
The last approved version of this historical standard is referenced on Available from the Fibre BoxAssociation, 500 Park Blvd, Suite 985, Itasca, IL
www.astm.org. 600143.
D5639/D5639M − 20
construction,orboth,commensuratewiththeiruser’sneedsfor structural rigidity, compression strength, and resistance to
packing and distribution of goods. This practice describes puncture. Triplewall is used for the heaviest contents where
several attributes of fiberboard and boxes which relate to
maximum structural rigidity, compression strength, and resis-
various hazards encountered in distribution and describes test tance to puncture are required.
parameters which may be specified by the user to ensure
7.1.1 Minimum basis weights for facings for mullen and
sufficient strength in the box for containment, storage,
puncture grades are spelled out in carrier rules. Facing basis
handling, transport and protection of contents.
weights for ECT grades are not specified in the shipping
regulations and may vary between suppliers and at times from
4.2 Theusershouldspecifyonlythoseattributesandrelated
tests which are required for performance to the users satisfac- a single supplier. While facing weight is not specified by rule
at a particular level for ECT grades, it is not good practice for
tion including their operations and distribution cycle(s). When
using the carriers’packaging rules as the major basis for the facing weights or flute structure to vary from run to run for
developing specifications, the reason for the rule and its any specified construction, mullen or ECT focused. Variation
function and importance should be understood. As previously in weight can affect box tare weight, height of loads of unused
stated, rules and regulations may be exceeded and should be boxes and fit of filled boxes in stacked loads.The basis weight
when the minimum specifications are inadequate for the full
selected for the initial design should be specified and used
effects of the distribution cycle, etc. If the user decides to
repeatedly in future orders unless the specifications are
employ box compression strength or a rough handling perfor-
changed.
mance protocol as the overriding specification, it should be
NOTE 2—Once a board combination is agreed upon between the box
noted that all minimum standards required by various organi-
supplierandtheircustomer,itissuggestedthatthecontractshowsthatthe
zations shall also be met or surpassed if using the related
board composition shall not be changed for subsequent orders without
certificate. These minimum standards can be stated in the box
consultation with the box customer. If changes to the board composition
drawing so as to ensure adherence to rules and regulations. If
are proposed, new performance testing procedures may be required.
a Box Manufacturer’s Certificate (BMC) is printed on the box,
7.1.2 Combined board caliper for a given board combina-
then the ECT or Mullen Burst/Basis Weight values shall meet
tionshouldnotvarybymorethanarangeof3–4milsfromrun
orexceedtheminimumrequirementsforsizeandweightofthe
torun.Consistencyinthicknessisnecessarytoensureefficient
packaged product.
mechanical erection, filling and sealing. Further, lower than
4.3 See Appendix X7 for several examples of specification
expected caliper is often indicative of crushed flutes and
determinations.
reduced panel stiffness which adversely affect box
performance,see7.5and7.7.Theexpectedcaliperselectedfor
5. Sampling
the initial design should be specified and used repeatedly in
5.1 Selection of a sampling plan depends on the purpose of future orders unless the specifications are changed.
the testing. The sampling plan from Appendix X2.2.2 of
7.1.3 Flute Types—A-flute offers the highest top-to-bottom
Practice D585 is recommended for acceptance criteria. An
compression strength, but low resistance to flat crush. B-flute
example of acceptance and rejection criteria based on various
hashighflatcrushresistancebutlowertop-to-bottomcompres-
lot sizes may be found in Appendix X1. For purposes of other
sionthan Aor C. B-fluteisthemostcommonflutetypeusedin
than acceptance criteria, use Practice E122.
Europe. C-flute is by far the most common flute type used in
the United States with average resistance to flat crush and
6. Conditioning
top-to-bottom compression. E-flute generally replaces solid
6.1 All test specimens shall be preconditioned, conditioned,
boxboard,hasexcellentflatcrushresistance,isusedmostlyfor
and tested in accordance with Practice D685.
graphics and consumer products, but seldom used for corru-
gated transport shipping containers. It should be noted that the
7. Fiberboard Attributes
Fibre Box Association (FBA) no longer attempts to define
NOTE 1—Corrugated fiberboard is commercially available in three wall
flutes precisely due to the large range of profiles and heights
constructions, and four common flute structures. The user should specify
being made around the world.The current version of the Fibre
desired wall construction and flute structure based on performance
requirements, though one should realize that definitions of flute size and Box Handbook, 2015, states the following (paraphrased):
shape vary from one manufacturer to another and from one country to
A-flute has about 33 flutes/ft, B-flute has about 47 flutes/ft,
another.As an example, if compression strength is the major specification
C-flutehasabout38flutes/ft,and E-flutehasabout90flutes/ft.
criteria — paper weight, flute size, and wall construction selection are
Please note the following table from Specification D4727/
often based on price for performance factors. One manufacturer may use
D4727M – 17 provides an approximate range of values:
lighter weight and or lower strength containerboard to form multi wall
corrugated board while another manufacturer may use heavier and or
Flutes/ft Flutes/m Flute Height [in.] Flute Height [mm]
stronger containerboard to form single wall corrugated board. While both
A-Flute 30 to 39 98 to 128 0.1575 to 0.2210 4.00 to 5.61
corrugatedboardsmaymeetstrengthrequirements,itshouldbenotedthat B-Flute 45 to 53 147 to 174 0.0787 to 0.1102 2.00 to 2.80
C-Flute 35 to 45 115 to 148 0.1300 to 0.1575 3.30 to 4.00
they may not operate the same in subsequent conversion, erecting, filling,
E-Flute 70 to 98 229 to 321 0.0445 to 0.0550 1.13 to 1.40
and handling operations.
7.2 Burst Strength—Theburstattributeiscommonlyrelated
7.1 Flute Structures—Singlewall board is used for lighter
contents where some structural rigidity, compression strength, to corrugated board toughness, tear and resistance to puncture,
rough handling of boxes. Boxes without adequate toughness
resistance to puncture, and cushioning is needed. Doublewall
board is used for heavier contents requiring a greater degree of can display score cracking and flap breakage.
D5639/D5639M − 20
7.2.1 Burst strength is measured by the burst (Mullen) test compression strength (for RSC boxes, see 8.1) through the a
utilizing TAPPI Method T810 and is specified in the carrier formula published in the August 1963 issue of Paperboard
rules for the various grades of singlewall and doublewall Packaging by the Institute of Paper Chemistry (now the
combined board. Renewable Bioproducts Institute.) part of Georgia Tech. It is
7.2.2 There is no direct relationship, such as a formula, to commonly known as the McKee Formula.Another, simplified,
relate box handling performance to needed burst strength. version of the McKee Formula was developed by George
However, as a function of box size and weight of the filled Maltenfort, and it too was published in theAugust 1963 issue
package, minimum burst strength requirements for corrugated of Paperboard Packaging. The simplified version utilizes the
packagingusedinsurfacecommoncarriertransportationinthe exponent values of box perimeter and board thickness instead
United States are published in the rail and truck classifications of the square root function, and the resultant box compression
and are shown in Table X2.1.The burst values shown in Table will be about 5% less compared to the simplified square root
X2.1 are the minimum values not the expected average burst method. The modified version is included in commercial
values for the grades. For example a nominal 200 lb/in. burst software programs for use by transport packaging designers.
specification is expected to average 220–240 lb/in. . These
NOTE 4—Compression values for other box designs, see 8.1, are often
requirements may or may not be appropriate for the user’s
estimated by ratio of RSC compression values to compression values of
applications.
the specific design under consideration. The buyer should contact the
supplier for details on expected BCT of the selected design.
7.2.2.1 The weight limits shown in Table X2.1 are for
individual packages. The calculated safety factor, F (see 1.3.1
7.4.1 The simplified McKee Formula is:
and 8.3.3) for boxes with these construction, product weights
BCT 5 5.87 3 ECT 3= BP 3 T (1)
~ ! ~ ! ~ ! ~ !
and box dimensions are in the range of 1–2. These weight
limitsmaybereasonableforboxeswhichhaveproductsupport
where:
for compression resistance.
BCT = estimated average top to bottom compression test
7.2.2.2 The weight limits shown in Table X2.1 are too high
strength of an RSC box, kN [lbf],
for corrugated fiberboard boxes that must support the entire
ECT = edge crush test, kN/m [lb/in.],
load in stacked storage and shipping applications. The weight
BP = inside box perimeter (sum of twice inside length and
limits provided in the freight rules table do not apply to how
twice inside width), m [in.], and
much load the boxes can support over time. For boxes
T = combined board thickness (caliper), m [in.].
providing the total compression resistance, box designers must
When solving for ECT using this formula, rearrange as
usecalculations(see7.4and8.3.3)todeterminesuitableboard
follows:
construction, ECT, and box size for a given product weight.
RequiredBCT
7.3 Resistance to Puncture—This attribute relates to the
Estimatedaverage ECT 5 (2)
5.87 3=BP 3 T
ability of the fiberboard to resist both internal and external
forces. It also relates to the rough handling integrity of the
See Appendix X4 for example and limitations of formula
finished container.
use.
7.3.1 Resistance to puncture is measured by the puncture
7.4.2 The exponent version of the McKee formula is:
test utilizing TAPPI Method T803 and is specified in the
0.508 0.492
BCT 5 5.87 3 ECT 3 T 3 BP (3)
carrier rules only for the various grades of triplewall (TW)
combined board.
where the terms are the same as for the simplified version.
7.3.2 There is no direct relationship, such as a formula, to
See Appendix X4 for an example of this formula in practice.
predict rough handling performance of a box based on the
The normal range of box compression values at standard
puncture resistance of the fiberboard from which it is made.
conditions as a function of ECT is shown by wall type in the
Shippers and carriers, however, have used various puncture
following table:
grades successfully for years as noted in Appendix X3. Table
Singlewall 2225–6675 N [500–1500 lb] (at perimeter 1.422–2.235 m
X3.1 lists suggested puncture strengths versus maximum gross
[56–88 in.]) – fits a 1.220 × 1.015 m [48 × 40 in.] pallet
Doublewall 6675–13 345 N [1500–3000 lb] (at perimeter 1.422–2.235 m
weights and size. These requirements may or may not be
[56–88 in.]) – fits a 1.220 × 1.015 m [48 × 40 in.] pallet
appropriate for all user’s applications. It is important to note
Triplewall 15 570–33 360 N [3500–7500 lb] (at perimeter 4.267 m [168 in.])
that as the basis weight of the facing increases to obtain higher
–fitsa1.220×1.015m[48×40in.]pallet
puncture resistance, ECT increases. As ECT increases, BCT
7.4.3 Edgewise crush resistance is measured by the edge-
increases. Therefore as puncture is a function of basis weight,
wise crush test (ECT) utilizingTAPPI MethodT811 orT839.
BCT is also a function of ECT and basis weight. The ECT
NOTE 5—These two tests yield slightly different test values; however,
values for triplewall boxes shown in the carrier rules have
for the purposes of this document either can be used to generate a rough
never been verified. For TW applications, the buyer should
estimate of box compression strength. The difference between the two
contact the supplier to obtain the appropriate minimum and
results is not important.
average ECT values for the grade being specified.
7.4.4 Although, as shown in 7.4.1, ECT directly relates to
NOTE 3—The 1100TWgrade for military applications is a special case
finished box compression strength, the rail and truck classifi-
that has a performance history. It has a minimum ECT value of 155 lb/in.
cations have minimum ECT requirements as an option other
7.4 Edgewise Crush Resistance (ECT)—This attribute of than minimum Burst Strength/Basis Weight requirements as
corrugated fiberboard boxes relates directly to the finished box shown in Table X4.1.
D5639/D5639M − 20
7.4.4.1 Please note that the tables show that ECT and However, these values can vary significantly by roll manufac-
mullengradescanbeusedtoaddressthesamepackageweights ture. The box supplier can supply the flute height used in their
and sizes. specific process.
7.5.2 Expectedcombinedboardcaliperandallowablevaria-
NOTE 6—This does not mean to imply that Burst and ECT are
tion in caliper for the specific box application may be reported
interchangeable, or that a relationship exists to convert from one to the
by the box supplier. See 7.1.2. The expected caliper and
other.BurstmaybemoreimportantforroughhandlingwhileECTmaybe
more important for stacking. expectedvariabilitymaybeincludedintheboxsupplycontract
if appropriate, particularly when automated equipment is
7.4.4.2 Both ECT and mullen grades have compression
involved.
strength aspects and burst aspects. The key difference is
7.5.2.1 The minimum typical acceptable caliper can be
betweenthetwogradetypesisthatmullengradesarenotmade
calculatedbyusingexpectedcaliperminusmaximumcrushing
with a focus on ECT strength and ECT grades while having a
deformation (see 7.7.1). Caliper loss greater than this amount
focus on ECT strength do not require the use of the same
indicates board crushing, which can result in loss of board
combined facing weight as is specified for mullen grades for
stiffness and a reduction in box compression strength.
similar box sizes and product weights.The net outcome is that
7.5.3 Test Method—The thickness of the combined board
the two grade types are roughly equivalent in general
structure can be measured using TAPPI Test Method T411.
performance,buttheECTgradesaremorelikelytobeuniform
andoptimizedinthecompressionaspectofperformanceandin
7.6 Combined Board Stiffness—This attribute is an indica-
cost while the mullen grades are likely to perform better in
tionoftherigidityoftheflutestructurewhichisinturndirectly
rough handling situations.
related to crush resistance during box fabrication and overall
7.4.4.3 These requirements may or may not be appropriate box rigidity.
for the user’s application.
7.6.1 Measures of board stiffness:
7.4.4.4 The ECT values as shown in Table X4.1 are the 7.6.1.1 Estimateimpactattheplantorcustomer–bycaliper
minimum values not the expected ECT average value for the loss, see 7.5 and 7.7.
grades.Forexamplethegradeshowingaminimumof32lb/in. 7.6.1.2 Flat crush strength as measured by TAPPI T 825 is
ECT is expected to have an actual ECT value of 35–41 lb/in. a measure of flute rigidity of corrugated board. Low flat crush
Box design is based on the expected average values, not the can indicate low resistance to crushing by the corrugating
minimum values. As tables in the shipping regulations and in medium (Concora, TAPPI T 809), leaning flutes, (a corrugator
Appendix X4 show only the minimum required ECTvalue per problem), and or crushed flutes(corrugator and finishing prob-
grade, it is good practice for the buyer to obtain average the lems). Low Flat Crush can impact the flexural stiffness of
ECT value(s) from the manufacturer and to include that corrugated board which can negatively affect box compression
information in the box specifications. as well as box performance in automatic case erection, filling
and sealing operations. Box clamp unit handling can also be
7.4.4.5 The approximate range of average ECT values for
Singlewall (SW), Doublewall (DW), and Triplewall (TW) are: negatively affected by low flat crush. Combined singlewall
fiberboard should meet the following minimum flat crush
Singlewall 4.730–13.500 kN/m [27–77 lb/in.]
Doublewall 8.755–18.385 kN/m [50–105 lb/in.] requirements for corrugating medium weighing 0.882 g/m
Triplewall 11.735–28.015 kN/m [67–160 lb/in.]
[26 lb/in ]:
7.4.5 Recent research calls into question the accuracy of 2
Flute kPa (lb/in )
performing edge crush testing on E-flute fiberboard. A 186 (27)
B 283 (41)
7.5 Combined Board Caliper—The overall thickness (cali-
C 234 (34)
per) of corrugated fiberboard is an important material attribute
7.6.1.3 Laboratory use of 4 point bending (TAPPIT836) to
relating to acceptable conversion, box forming/erecting, filling
quantify board stiffness is beyond the scope of this document.
and palletizing. Caliper is also related to finished box panel
7.7 Crush—Excessive crush of fiberboard in its thickness
stiffness and box compression strength.
direction from feed rolls or excess printing impression will
7.5.1 Maximum theoretical caliper is a function of the
reduce the bending (stiffness) of the board structure. This
height of the flute formed on the corrugator and the thickness
reduces compression strength of the finished box and can
of the materials used.Actual caliper is also impacted by paper
adversely affect automatic packing equipment and warehouse
compressibility, roll wear and loss of thickness to crushing
stacking performance.
among other factors.
7.7.1 Thefollowingaresuggested maximumcrushdeforma-
7.5.1.1 Corrugated board flute height is determined by the
tionsforsinglewall(SW)boardsduetofeedrollsandprinting:
flute profile of the corrugating rolls used. Each of the flute
A-flute 0.25 mm [0.010 in.]
types has a range of possible flute height and a most common
B-flute 0.15 mm [0.006 in.]
value. Common values for A, B, and C-flute are 4.675, 2.465,
C-flute 0.20 mm [0.008 in.]
and 3.630 mm [0.184, 0.097, and 0.143 in.], respectively.
7.7.2 For doublewall (DW) boards use 75% of the combi-
nation of flute structure allowances, for triplewall (TW) use
50%(thatis,AAA-flutehasmaximumallowablecrushof0.30
Wilson, C., and Frank, B., TAPPI Journal, June 2009. mm [0.012 in.]).
D5639/D5639M − 20
7.7.3 Test Method—Using TAPPI Test Method T411 mea- strength in storage and transportation for boxes where the box
sure the board sample at least 25 mm [1 in.] from any score itselfprovidesmostoralloftherequiredcompressionstrength.
line, cut edge, or printed area. Then measure it in the printed This both protects the contents from damage and maintains
area and subtract from the first reading to determine amount of stacks from toppling over due to crushing container walls.
crush deformation. Minimum box compression strength (BCT) as measured by
Test Method D642 is often the key value in box specification.
8.
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5639/D5639M − 11 (Reapproved 2015) D5639/D5639M − 20
Standard Practice for
Selection of Corrugated Fiberboard Materials and Box
Construction Based on Performance Requirements
This standard is issued under the fixed designation D5639/D5639M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This practice provides information on corrugated fiberboard for the prospective user who wants guidance in selecting attributes
of materials and box construction based on performance requirements. These attributes should be part of specifications which
establish levels of the qualities a shipping container shall have achieved in order to be acceptable to the purchaser or user. The
attributes and qualities should be testable, using standard methods that are recognized by both the buyer and seller. This practice
will assist users in developing specifications for corrugated containers through an analysis of performance requirements and
subsequent relationships to fiberboard materials and box construction attributes. This practice is intended to provide specific
corrugated container performance standards as opposed to packaged product performance evaluation through distribution and
handling environments, such as Practicemeant to complement the box buyer–box manufacturer relationship by having the buyer
(user) better understand, discuss, and negotiate needed elements of box D4169.design and specification. The full box design
process is complex, and it is beyond the scope of this standard.
1.2 The attributes and their levels should be based on the intended use of the box, including the handling and environment it will
encounter. Many packaging regulationsrules include detailed descriptions of the materials that may be used and style, closure, or
other construction details of allowed shipping containers. These regulationsrules are presented as minimum requirements; they may
be exceeded for functional reasons, but there is no regulatory reason to do so. Rail and motor freight classifications applicable for
surface common carrier transportation have established minimum requirements for certain attributes of corrugated packaging.
These may or may not be appropriate for application in the complete distribution system, as they encompass only containerboard
or combined corrugated board—not finished boxes—and board — not finished boxes — and are not intended to provide for the
distribution and storage system beyond the transportation segment.
1.2.1 The attribute levels contained herein are based on USU.S. practice and specifications. Some attributes such as flute
dimensions and basis weights may be defined differently in other countries.
1.3 There are two distinctly different methods commonly four common methods used for specifying boxes. The most common
approach is to specify materials, such as defining flute, edge crush value, Mullen burst value, and flat crush minimums,
containerboard weights and thicknesses. An alternative approach is to define some measure of performance. Mullen burst values
can be one of these measures if the user has determined that some minimum burst value is all that is required in their distribution
system. The overall compression strength of the box is another, and this measure allows each supplier to achieve the required
strength through their own unique combination of materials and processes. A third measure would be to pass some sort of rough
handling performance protocol, with Practice D4169 being one example. Unlike material specifications, where definitions of
fluting, test methods of ECT, and difficulty of assessing individual components of the box structure exist, compression values of
This practice is under the jurisdiction of ASTM Committee D10 on Packaging and is the direct responsibility of Subcommittee D10.27 on Paper and Paperboard
ProductsFiberboard Shipping Containers, Containerboard and Related Structures and Materials.
Current edition approved Oct. 1, 2015Oct. 1, 2020. Published October 2015December 2020. Originally approved in 1994. Last previous edition approved in 20112015
as D5639/D5639M – 11.D5639/D5639M – 11 (2015). DOI: 10.1520/D5639_D5639M-11R15.10.1520/D5639_D5639M-20.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5639/D5639M − 20
the finished box are easily tested and verified using a common test method (Test Method D642). The same can be said of box
performance measured against a performance protocol. Using only material specifications to define a box does not guarantee the
box will be well made. For example, the best possible material could be used for making a box, but if the score lines are too deep
or too shallow, or if the manufacturer’s joint is not secured correctly, the box will fail in distribution.
Conversely, box compression and rough handling performance protocols measures both material and manufacturing quality
simultaneously. It is sometimes advantageous to use a combination of both these methods to help assure the outer liner will not
easily scuff or break. Though suppliers will need to continue to use material specifications when making boxes, the user would
benefit more from employing performance specifications to help guarantee similar box attributes from a variety of suppliers. It
should be realized that no two suppliers, especially if they’re located in different countries, will use the same materials and
processes for making a box. Employing box compression values or performance protocols will help assure the lowest price for
specific performance, regardless of the material used.
1.3.1 A common approach is to examine boxes currently in use for the specific application and to make a similar or modified
version of that box, given that it has a proven performance record. This method, while quite efficient, and fast, does not lead to
box optimization based on characterization by end use. This method can lead to overdesign.
1.3.2 A second common approach is to estimate the compression strength necessary for a box at the bottom of a stack of boxes
to totally support the anticipated load. A safety factor, F, is calculated from the expected environmental hazards that are anticipated
in storage and shipping. A minimum initial box compression, as measured by Test Method D642 is determined using the weight
on the bottom box and the F factor, see 8.3. Then engineering principles are used to select material combinations based on material
characteristics such as caliper, edge crush value, and flat crush to meet that requirement.
1.3.3 The third approach may be used when the box application has product support sufficient to meet anticipated compression
requirements, therefore the board structural requirements are focused on protection and containment. Mullen burst values can be
one of these measures for this category of box if the user has determined that a minimum burst value is the main metric required
in their distribution system. In this case, total weight per box allowable per carrier rules may be higher than would be expected
based on expected predicted compression strength, safety factor, and board combination used. See 7.2 – 7.2.2.2 and 8.2.1.
1.3.4 The fourth approach may be used when the box is intended for single parcel shipment of high value or hazardous materials,
where there can be a compression requirement but most often the performance attributes required are toughness as measured by
drop and impact resistance, see 8.2. A means of gaining confidence that a box in this category will function properly in its intended
distribution environment is to test the box using some sort of rough handling performance protocol such as Practice D4169 or ISTA
3 Series: General Simulation Performance Tests.
1.3.5 Using material specifications to define a box does not guarantee the box will be well made. For example, the best possible
material could be used for making a box, but if the score lines are too deep or too shallow, or if the manufacturer’s joint is not
secured correctly, the box will fail in distribution. All proposed constructions and designs should be vetted by means of a process
of samples, testing, prototype packing and shipping. Only once a construction has been proven to work across a range of
anticipated end use conditions should it be approved for normal production.
1.4 Corrugated containers for packaging of hazardous materials for transportation shall comply with federal regulations
administered by the U.S. Department of Transportation (Code of Federal Regulations, CFR 49).Title 49).
1.5 Lists and Descriptions of Performance and Material Characteristics and Related Test Procedures—For further information on
the development of performance-based specifications, please refer to the sections on Specifications and Test Procedures of the
Fibre Box Handbook.
1.6 The values stated in both SI and inch-pound units are to be regarded separately as standard. Within the text, the inch-pound
units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used
independently of the other.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.8 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
D5639/D5639M − 20
2. Referenced Documents
2.1 ASTM Standards:
D585 Practice for Sampling and Accepting a Single Lot of Paper, Paperboard, Fiberboard, and Related Product (Withdrawn
2010)
D642 Test Method for Determining Compressive Resistance of Shipping Containers, Components, and Unit Loads
D685 Practice for Conditioning Paper and Paper Products for Testing
D996 Terminology of Packaging and Distribution Environments
D1968 Terminology Relating to Paper and Paper Products
D2658 Test Method for Determining Dimensions of Fiberboard Boxes
D4169 Practice for Performance Testing of Shipping Containers and Systems
D4727/D4727M Specification for Corrugated and Solid Fiberboard Sheet Stock (Container Grade) and Cut Shapes
D5118/D5118M Practice for Fabrication of Fiberboard Shipping Boxes
D5168 Practice for Fabrication and Closure of Triple-Wall Corrugated Fiberboard Containers
D5276 Test Method for Drop Test of Loaded Containers by Free Fall
D7386 Practice for Performance Testing of Packages for Single Parcel Delivery Systems
E122 Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot or
Process
2.2 TAPPI Methods:
T 411 Thickness of Paper, Paperboard, and Combined Board
T 803 Puncture Test of Corrugated Fiberboard
T 808T 809 Flat Crush Test of Corrugated Fiberboard-Flexible Beam MethodCorrugating Medium (CMT Test)
T 810 Burst Test of Corrugated Fiberboard
T 811 Edgewise Crush Test of Corrugated Fiberboard
T 825 Flat Crush Test of Corrugated Fiberboard-Fixed Platen Method
T 836 Bending Stiffness, Four Point Method
T 839 Edgewise Compressive Strength of Corrugated Fiberboard Using the Clamp Method (Short Column Test)
2.3 Government Documents:
CFR 49 Code of Federal Regulations, Title 49 §178.516 – Standards for Fiberboard Boxes
2.4 Other Publications:Carrier Rules:
Fibre Box Handbook
Edge Crush Test, Application and Reference Guide for Combined Corrugated Board, Fibre Box Association
National Motor Freight Classification Item 222 Item 222
Uniform Freight Classification Rule 41 Rule 41
2.5 Other Publications:
ISTA Testing Guidelines, Testing Procedures
Fibre Box Handbook
3. Terminology
3.1 Definitions—For general definitions of packaging and distribution environments, see Terminology D996. For paper and
combined board related terms see Terminology D1968.
4. Significance and Use
4.1 This practice assists users in selecting appropriate performance characteristics of corrugated fiberboard or box construction,
or both, commensurate with the user’s needtheir user’s needs for packing and distribution of goods. This practice describes several
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
Available from Technical Association of the Pulp and Paper Industry (TAPPI), 15 Technology Parkway South, Norcross, GA 30092, http://www.tappi.org.
Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
www.access.gpo.gov.
Available from the Fibre Box Association, 25 Northwest Point Blvd., Suite 510, Elk Grove Village, IL 60007.
Available from the National Motor Freight Traffic Association (NMFTA), 1001 N Fairfax St, Suite 600, Alexandria, VA 22314-1748.
Available from National Railroad Freight Committee, Tariff Publishing Officer, 151 Ellis Street, NE, Suite 200, Atlanta, GA 30335.
Available from ISTA Distributing Confidence, Worldwide TM 1400 Abbott Road, Suite 160 East Lansing, MI 48823; www.ista.org
Available from the Fibre Box Association, 500 Park Blvd, Suite 985, Itasca, IL 600143.
D5639/D5639M − 20
attributes of fiberboard and boxes which relate to various hazards encountered in distribution and describes test parameters which
may be specified by the user to ensure sufficient strength in the box for containment, storage, handling, transport and protection
of contents.
4.2 The user should specify only those attributes and related tests which are required for satisfactory performance in the user’s
to the users satisfaction including their operations and distribution cycle(s). When using packaging regulations as a the
carriers’packaging rules as the major basis for developing specifications, the reason for the existence of the regulation rule and its
function and importance should be understood. As previously stated, rules and regulations may be exceeded and should be when
the minimum specifications are inadequate for the full effects of the distribution cycle. cycle, etc. If the user decides to employ
box compression strength or a rough handling performance protocol as the overriding specification, it should be noted that all
minimum standards required by various organizations shall also be met or surpassed. surpassed if using the related certificate.
These minimum standards can be stated in the box drawing so as to ensure adherence to regulations rules and regulations. If a Box
Manufacturer’s Certificate (BMC) is printed on the box, then the ECT or Mullen Burst/Basis Weight values shall meet or exceed
the minimum requirements for size and weight of the packaged product.
4.3 See Appendix X7 for several examples of specification determinations.
5. Sampling
5.1 Selection of a sampling plan depends on the purpose of the testing. The sampling plan from Appendix X2.2.2 of Practice D585
is recommended for acceptance criteria. An example of acceptance and rejection criteria based on various lot sizes may be found
in Appendix X1. For purposes of other than acceptance criteria, use Practice E122.
6. Conditioning
6.1 All test specimens shall be preconditioned, conditioned, and tested in accordance with Practice D685.
7. Fiberboard Attributes
NOTE 1—Corrugated fiberboard is commercially available in three wall constructions, and four common flute structures. The user should specify desired
wall construction and flute structure based on performance requirements, though one should realize that definitions of flute size and shape vary from one
manufacturer to another and from one country to another. As an example, if compression strength is the major specification criteria — paper weight, flute
size, and wall construction selection are often based on price for performance factors. One manufacturer may use lighter weight and or lower strength
containerboard to form multi wall corrugated board while another manufacturer may use heavier and or stronger containerboard to form single wall
corrugated board. While both corrugated boards may meet strength requirements, it should be noted that they may not operate the same in subsequent
conversion, erecting, filling, and handling operations.
7.1 Flute Structures—Corrugated fiberboard is commercially available in three wall constructions, and four common flute
structures. The user should specify desired wall construction and flute structure based on performance requirements, though one
should realize that definitions of flute size and shape vary from one manufacturer to another and from one country to another. In
contrast, if compression strength is the specification, then paper weight, flute size, and wall construction are all based on price for
performance, perhaps allowing one manufacturer to use thin weak paper to form double wall while another uses better quality
paper and processes to use single wall. Singlewall board is used for lighter contents where some structural rigidity, compression
strength, resistance to puncture, and cushioning is needed. Doublewall board is used for heavier contents requiring a greater degree
of structural rigidity, compression strength, and resistance to puncture. Triplewall is used for the heaviest contents where maximum
structural rigidity, compression strength, and resistance to puncture are required.
7.1.1 Minimum basis weights for facings for mullen and puncture grades are spelled out in carrier rules. Facing basis weights for
ECT grades are not specified in the shipping regulations and may vary between suppliers and at times from a single supplier. While
facing weight is not specified by rule at a particular level for ECT grades, it is not good practice for the facing weights or flute
structure to vary from run to run for any specified construction, mullen or ECT focused. Variation in weight can affect box tare
weight, height of loads of unused boxes and fit of filled boxes in stacked loads. The basis weight selected for the initial design
should be specified and used repeatedly in future orders unless the specifications are changed.
NOTE 2—Once a board combination is agreed upon between the box supplier and their customer, it is suggested that the contract shows that the board
composition shall not be changed for subsequent orders without consultation with the box customer. If changes to the board composition are proposed,
new performance testing procedures may be required.
7.1.2 Construction—Singlewall board is used for lighter contents where some structural rigidity, compression strength, resistance
D5639/D5639M − 20
to puncture, and cushioning is needed. Doublewall board is used for heavier contents requiring a greater degree of structural
rigidity, compression strength, and resistance to puncture. Triplewall is used Combined board caliper for a given board combination
should not vary by more than a range of 3–4 mils from run to run. Consistency in thickness is necessary to ensure efficient
mechanical erection, filling and sealing. Further, lower than expected caliper is often indicative of crushed flutes and reduced panel
stiffness which adversely affect box performance, see 7.5 and 7.7for the heaviest contents where maximum structural rigidity,
compression strength, and resistance to puncture are required. The expected caliper selected for the initial design should be
specified and used repeatedly in future orders unless the specifications are changed.
7.1.3 Flute Structure—Types—A-flute offers the highest top-to-bottom compression strength, but low resistance to flat crush.
B-flute has high flat crush resistance but lower top-to-bottom compression than A or C.B-flute is the most common flute type used
in Europe. C-flute is by far the most common flute type used in the United States with average resistance to flat crush and
top-to-bottom compression. E-flute generally replaces solid boxboard, has excellent flat crush resistance, is used mostly for
graphics and consumer products, but seldom used for corrugated transport shipping containers. It should be noted that the Fibre
Box Association (FBA) no longer attempts to define flutes precisely due to the large range of profiles and heights being made
around the world. The current version of the Fibre Box Handbook, (2005),2015, states the following (paraphrased): A-flute has
about 33 flutes/ft, B-flute has about 47 flutes/ft, C-flute has about 3938 flutes/ft, and E-flute has about 90 flutes/ft.”flutes/ft. Please
note the following table from Specification D4727/D4727M–07 provides only – 17 provides an approximate range of values:
Flutes/ft Flutes/m Flute Height [in.] Flute Height [mm]
A-Flute 30 to 39 98 to 128 0.1575 to 0.2210 4.00 to 5.61
B-Flute 45 to 53 147 to 174 0.0787 to 0.1102 2.00 to 2.80
C-Flute 35 to 45 115 to 148 0.1300 to 0.1575 3.30 to 4.00
E-Flute 70 to 98 229 to 321 0.0445 to 0.0550 1.13 to 1.40
7.2 Burst Strength—This attribute relates to the tensile strength and stretch elongation of the fiberboard. It also provides rupture
strength as protection against rough handling.The burst attribute is commonly related to corrugated board toughness, tear and
resistance to puncture, rough handling of boxes. Boxes without adequate toughness can display score cracking and flap breakage.
7.2.1 Burst strength is measured by the burst (Mullen) test utilizing TAPPI Method T 810 and is specified in the carrier
regulationsrules for the various grades of singlewall and doublewall combined board.
7.2.2 There is no direct relationship, such as a formula, to relate box handling performance to needed burst strength. However,
as a function of box size and weight of the filled package, minimum burst strength requirements for corrugated packaging used
in surface common carrier transportation in the United States are published in the rail and truck classifications and are shown in
Table X2.1. The burst values shown in Table X2.1 are the minimum values not the expected average burst values for the grades.
2 2
For example a nominal 200 lb/in. burst specification is expected to average 220–240 lb/in. . These requirements may or may not
be appropriate for the user’suser’s applications.
7.2.2.1 The weight limits shown in Table X2.1 are for individual packages. The calculated safety factor, F (see 1.3.1 and 8.3.3)
for boxes with these construction, product weights and box dimensions are in the range of 1–2. These weight limits may be
reasonable for boxes which have product support for compression resistance.
7.2.2.2 The weight limits shown in Table X2.1 are too high for corrugated fiberboard boxes that must support the entire load in
stacked storage and shipping applications. The weight limits provided in the freight rules table do not apply to how much load the
boxes can support over time. For boxes providing the total compression resistance, box designers must use calculations (see 7.4
and 8.3.3) to determine suitable board construction, ECT, and box size for a given product weight.
7.3 Resistance to Puncture—This attribute relates to the ability of the fiberboard to resist both internal and external forces. It also
relates to the rough handling integrity of the finished container.
7.3.1 Resistance to puncture is measured by the puncture test utilizing TAPPI Method T 803 and is specified in the carrier
regulationsrules only for the various grades of triplewall (TW) combined board.
7.3.2 There is no direct relationship, such as a formula, to predict rough handling performance of a box based on the puncture
resistance of the fiberboard from which it is made. Shippers and carriers, however, have used various puncture grades successfully
for years as noted in Appendix X3. Table X3.1 lists suggested puncture strengths versus maximum gross weights and size. These
requirements may or may not be appropriate for the user’s application. all user’s applications. It is important to note that as the
basis weight of the facing increases to obtain higher puncture resistance, ECT increases. As ECT increases, BCT increases.
D5639/D5639M − 20
Therefore as puncture is a function of basis weight, BCT is also a function of ECT and basis weight. The ECT values for triplewall
boxes shown in the carrier rules have never been verified. For TW applications, the buyer should contact the supplier to obtain
the appropriate minimum and average ECT values for the grade being specified.
NOTE 3—The 1100 TW grade for military applications is a special case that has a performance history. It has a minimum ECT value of 155 lb/in.
7.4 Edgewise Crush Resistance (ECT)—This attribute of corrugated fiberboard boxes relates directly to the finished box
compression strength (for RSC boxes, see 8.1) through the well-known simplified a formula published in 1963 the August 1963
issue of Paperboard Packaging by the Institute of Paper Chemistry (now the Institute of Paper Science and Technology, or IPST)
andRenewable Bioproducts Institute.) part of Georgia Tech. It is commonly known as the McKee Formula. Another widely used
Another, simplified, version of the McKee Formula, known as the modified version, Formula was developed by George Maltenfort,
and it too was published in the August 1963 issue of Paperboard Packaging. The simplified version utilizes the exponent values
of box perimeter and board thickness instead of the square root function, and the resultant box compression will be about 5 % less
compared to the simplified square root method. The modified version is included in commercial software programs for use by
transport packaging designers.
NOTE 4—Compression values for other box designs, see 8.1, are often estimated by ratio of RSC compression values to compression values of the specific
design under consideration. The buyer should contact the supplier for details on expected BCT of the selected design.
7.4.1 The simplified McKee Formula is:
BCT 5 5.87 3 ECT 3= BP 3 T (1)
~ ! ~ ! ~ ! ~ !
where:
BCT = estimated average top to bottom compression test strength of an RSC box, kN [lbf],
ECT = edge crush test, kN/m [lb/in.],
BP = inside box perimeter (sum of twice inside length and twice inside width), m [in.], and
T = combined board thickness (caliper), m [in.].
When solving for ECT using this formula, rearrange as follows:
Required BCT
Estimated average ECT 5 (2)
5.87 3=BP 3T
See Appendix X4 for example and limitations of formula use.
7.4.2 The exponent version of the McKee formula is:
0.508 0.492
BCT 5 5.87 3ECT 3T 3BP (3)
where the terms are the same as for the simplified version. See Appendix Appendix X4 for an example of this formula in
practice. The normal range of box compression values at standard conditions as a function of ECT is shown by wall type in the
following table:
Singlewall 2225–6675 N [500–1500 lb] (at perimeter 1.422–2.235 m
[56–88 in.]) – fits a 1.220 × 1.015 m [48 × 40 in.] pallet
Doublewall 6675–13 345 N [1500–3000 lb] (at perimeter 1.422–2.235 m [56–88 in.]) – fits a 1.220 × 1.015 m [48 × 40 in.] pallet
Triplewall 15 570–33 360 N [3500–7500 lb] (at perimeter 4.267 m [168 in.]) – fits a 1.220 × 1.015 m [48 × 40 in.] pallet
7.4.3 Edgewise crush resistance is measured by the edgewise crush test (ECT) utilizing TAPPI Method T 811.T 811 or T 839.
NOTE 5—These two tests yield slightly different test values; however, for the purposes of this document either can be used to generate a rough estimate
of box compression strength. The difference between the two results is not important.
7.4.4 Although, as shown in 7.4.1, ECT directly relates to finished box compression strength, the rail and truck classifications have
minimum ECT requirements as an alternate to option other than minimum Burst Strength/Basis Weight requirements as shown in
Table X4.1. These requirements may or may not be appropriate for the user’s application.
7.4.4.1 Please note that the tables show that ECT and mullen grades can be used to address the same package weights and sizes.
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NOTE 6—This does not mean to imply that Burst and ECT are interchangeable, or that a relationship exists to convert from one to the other. Burst may
be more important for rough handling while ECT may be more important for stacking.
7.4.4.2 Both ECT and mullen grades have compression strength aspects and burst aspects. The key difference is between the two
grade types is that mullen grades are not made with a focus on ECT strength and ECT grades while having a focus on ECT strength
do not require the use of the same combined facing weight as is specified for mullen grades for similar box sizes and product
weights. The net outcome is that the two grade types are roughly equivalent in general performance, but the ECT grades are more
likely to be uniform and optimized in the compression aspect of performance and in cost while the mullen grades are likely to
perform better in rough handling situations.
7.4.4.3 These requirements may or may not be appropriate for the user’s application.
7.4.4.4 The ECT values as shown in Table X4.1 are the minimum values not the expected ECT average value for the grades. For
example the grade showing a minimum of 32 lb/in. ECT is expected to have an actual ECT value of 35–41 lb/in. Box design is
based on the expected average values, not the minimum values. As tables in the shipping regulations and in Appendix X4 show
only the minimum required ECT value per grade, it is good practice for the buyer to obtain average the ECT value(s) from the
manufacturer and to include that information in the box specifications.
7.4.4.5 The approximate range of average ECT values for Singlewall (SW), Doublewall (DW), and Triplewall (TW) are:
Singlewall 4.730–13.500 kN/m [27–77 lb/in.]
Doublewall 8.755–18.385 kN/m [50–105 lb/in.]
Triplewall 11.735–28.015 kN/m [67–160 lb/in.]
7.4.5 Recent research calls into question the accuracy of performing edge crush testing on E-flute fiberboard.
7.5 Minimum Uncombined Flute Height—Combined Board Caliper—The overall thickness (caliper) of corrugated fiberboard is
an important material attribute relating directly to finished box compression strength. Since thickness consists primarily of the flute
structures,to acceptable conversion, box forming/erecting, filling and palletizing. Caliper is also related to minimumfinished flute
heights may be specified,box panel stiffness and box notcompression including any linerboard (facings). strength.
7.5.1 To determine minimum flute heights, use the corrugated fiberboard manufacturer’s target flute heights,Maximum theoretical
caliper is a function of the height of the flute formed on the corrugator and the thickness of the minusmaterials 4 %.used. Actual
caliper is also impacted by paper compressibility, roll wear and loss of thickness to crushing among other factors.
7.5.1.1 Corrugated board flute height is determined by the flute profile of the corrugating rolls used. Each of the flute types has
a range of possible flute height and a most common value. Common values for A,B, and C-flute are 4.675, 2.465, and 3.630 mm
[0.184, 0.097, and 0.143 in.], respectively. However, these values can vary significantly by roll manufacture. The box supplier can
supply the flute height used in their specific process.
7.5.2 Users specifying box compression strength or a rough handling performance protocol need not specify and control flute
heights, ECT, or flat crush parameters, though the supplier must. Instead of focusing on components of the box, the userExpected
combined board caliper and allowable variation in caliper for the specific box application may be reported by the box supplier. See
7.1.2will focus more on the performance of the final box, though some users will need to also require minimum outer liner basis
weights, or perhaps Mullen burst values, to avoid problems in distribution. The expected caliper and expected variability may be
included in the box supply contract if appropriate, particularly when automated equipment is involved.
7.5.2.1 The minimum typical acceptable caliper can be calculated by using expected caliper minus maximum crushing
deformation (see 7.7.1). Caliper loss greater than this amount indicates board crushing, which can result in loss of board stiffness
and a reduction in box compression strength.
7.5.3 Test Method—First measure the The thickness of the combined board structure can be measured using TAPPI Test Method
T 411. Then measure the thickness of each facing (linerboard), without soaking apart, and subtract the thickness of the facings to
obtain flute structure(s) height. All readings shall be taken at least 25 mm [1 in.] from any score line, cut edge, or printed area.
C. Wilson and B. Frank, TAPPI Journal, June, 2009.Wilson, C., and Frank, B., TAPPI Journal, June 2009.
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7.6 Flat Crush Resistance—Combined Board Stiffness—This attribute is an indication of the rigidity of the flute structure which
is in turn directly related to crush resistance during box fabrication and overall box rigidity.
7.6.1 Combined singlewall fiberboard should meet the following minimum flat crush requirements for corrugating medium
2 2
weighing 0.882 g/mMeasures of board stiffness: [26 lb/in ]:
Flute Flexible Beam Method, kPa [lbf/in. ]
A 130 [19]
B 200 [29]
C 165 [24]
7.6.1.1 Estimate impact at the plant or customer – by caliper loss, see 7.5 and 7.7.
7.6.1.2 Flat crush strength as measured by TAPPI T 825 is a measure of flute rigidity of corrugated board. Low flat crush can
indicate low resistance to crushing by the corrugating medium (Concora, TAPPI T 809), leaning flutes, (a corrugator problem), and
or crushed flutes(corrugator and finishing problems). Low Flat Crush can impact the flexural stiffness of corrugated board which
can negatively affect box compression as well as box performance in automatic case erection, filling and sealing operations. Box
clamp unit handling can also be negatively affected by low flat crush. Combined singlewall fiberboard should meet the following
2 2
minimum flat crush requirements for corrugating medium weighing 0.882 g/m [26 lb/in ]:
Flute kPa (lb/in )
A 186 (27)
B 283 (41)
C 234 (34)
7.6.1.3 Laboratory use of 4 point bending (TAPPI T 836) to quantify board stiffness is beyond the scope of this document.
7.6.2 Flat crush resistance is measured by the flat crush test (FCT). The above values are measured by using the flexible beam
test method of TAPPI T 808. An alternate method utilizing the fixed beam, TAPPI T 825, is also available but will produce values
about 20 to 30 % higher.
7.7 Crush—Excessive crush of fiberboard in its thickness direction from feed rolls or excess printing impression will reduce the
bending (stiffness) of the board structure. This reduces compression strength of the finished box and can adversely affect automatic
packing equipment and warehouse stacking performance.
7.7.1 The following are suggested maximum crush deformations for singlewall (SW) boards due to feed rolls and printing:
A-flute 0.25 mm [0.010 in.]
B-flute 0.15 mm [0.006 in.]
C-flute 0.20 mm [0.008 in.]
A-flute 0.25 mm [0.010 in.]
B-flute 0.15 mm [0.006 in.]
C-flute 0.20 mm [0.008 in.]
7.7.2 For doublewall (DW) boards use 75 % of the combination of flute structure allowances, for triplewall (TW) use 50 % (that
is, AAAAAA-flute-flute has maximum allowable crush of 0.30 mm [0.012 in.]).
7.7.3 Test Method—Using TAPPI Test Method T 411 measure the board sample at least 25 mm [1 in.] from any score line, cut
edge, or printed area. Then measure it in the printed area and subtract from the first reading to determine amount of crush
deformation.
7.7.4 Users specifying compression strength can avoid specifying overall crush and print crush, leaving this detail to the
manufacturer to control while achieving the minimum compression strengths required for all boxes produced. Manufacturers who
control these kinds of attributes the best will benefit from lower costs to meet minimum performance requirements.
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8. Finished Container Attributes
8.1 Box Style—A wide variety of box styles are available to the user ranging from the most common Regular Slotted Container
((RSC,RSC) International Box Code 201) to specialized styles configured for particular applications. The more common styles are
depicted in Practice D5118/D5118M, Figures 1 through 14 and in the Fibre Box Handbook. In addition, rigid boxes formed by
automatic in-plant equipment may be appropriate and include the following styles: Bliss, Bliss with tri-fold ends; Bliss with
internal flange; Bliss with triangular corner posts; Bliss with integral “H” divider; Tray with side flange sealed flaps; Tray, six
corners glued; Tray with triangular corner posts; and Tray split minor. The user should specify the style which is most economical
in view of requirements for packing, closure, protection, handling, storage, and transportation.
8.2 Containment Strength—The basic purpose of a corrugated box is to contain the product in such a way that the product can be
moved safely through the entire distribution cycle. A method of determining containment strength of a box is to conduct drop tests
which stress its fibers and structure in a manner similar to that imposed by various environmental hazards. This test is appropriate
for common carrier trucking and small parcel shipments, but may not be appropriate for unitized or full truckload or railcar-load
shipments.
8.2.1 Boxes stored or shipped in stacks which have internal product support for compression strength but which also need
toughness to contain heavy or irregular shaped contents are often made with containment grades for this type of shipment.
8.2.2 The test method recommended for measurement of containment strength of corrugated boxes is a free fall drop of loaded
containers in accordance with Test MethodBoxes with high value or hazardous material contents that are shipped by common
carrier trucking or in small parcel shipments are often evaluated using drop D5276. Seetests. These Appendix X5 for drop sequence
and suggested drop heights. A different drop test procedure may be selected from Test Method tests stress its fibers and structure
in a manner like that imposed by various environmental hazards. This type D5276, Annex A2; or one may also create different
sequences of drop and orientations based on experience including multiple test specimens each tested differently in sequence and
drop height.of testing may not be appropriate for unitized or full truckload or railcar-load shipments.
8.2.2.1 The test method recommended for measurement of containment strength of corrugated boxes is a free fall drop of loaded
containers in accordance with Test Method D5276. See Appendix X5 for drop sequence and suggested drop heights. A different
drop test procedure may be selected from Test Method D5276, Annex A2; or one may create different sequences of drop and
orientations based on experience including multiple test specimens each tested differently in sequence and drop height. Practice
3 3
D7386 shows how to calculate required BCT for boxes in drop testing, based on single parcel density of 190 kg/m [12 lb/ft ].
8.2.2.2 For the dropping mass, use the actual product (or a dummy load of similar shape, size, weight, and dynamic characteristics)
with the same interior packaging as generally used.
8.2.2.3 The container fails if it does not meet acceptance criteria previously determined. The required condition of the container
at receipt by the ultimate customer should be the primary test criteria.
8.2.2 For the dropping mass, use the actual product (or a dummy load of similar shape, size, weight, and dynamic characteristics)
with the same interior packaging as generally used.
8.2.3 The container fails if it does not meet acceptance criteria previously determined. This criteria should consider the required
condition of the container at receipt by the ultimate customer.
8.3 Top to Bottom Stacking Strength—A major function of the corrugated container is to provide sufficient stacking strength in
storage and transportation for the dual purpose of protecting the boxes where the box itself provides most or all of the required
compression strength. This both protects the contents from damage and maintainingmaintains stacks from toppling over due to
crushing container walls. Minimum box compression strength (BCT) as measured by Test Method D642 is often the key value in
box specification. Buyers should obtain BCT information from the manufacturer and include that information in the box
specifications.
8.3.1 Using Test Method An D642, measure the resistance of corrugated boxes to stacking loads and provide an indication as to
the amount of safe load it indication of the safe load that a box can withstand in normal stacking situations.stacking can be
determined by BCT using the appropriate safety factor. The estimated target BCT can be calculated by multiplying the weight on
the bottom box in a stack times the safety factor.
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8.3.1.1 The range of normal F factors used by industry are:
Rapid use, normal humidity, mild abuse or misaligned stacks F
range = 3–5
Use within a 100 days, slightly elevated humidity, cross stacking
F range = 5–7
Storage over 100 days, humidity to 80 %, and cross stacking F
range = 8–10
Storage over 100 days, humidity 85–90 %, cross stacking with
over-hang F = 12+
8.3.1.2 The range of normal F factors specified in Practice D4169, 11.2, for type 1 boxes:
Minimum (Assurance Level III) F range = 3-5
Mid-Range (Assurance Level II) F range = 4.5-7
Highest (Assurance Level I) F range = 8-10
8.3.1.3 Safety, F, factors can be calculated using the subfactors and process shown in Table X6.1.
8.3.2 Test Method D642 permits either fixed or floating platens. Since fixed platen machines generally cause failure to occur at
the specimen’sspecimen’s strongest point, while swivel platen machines cause failure at the specimen’sspecimen’s weakest point,
only one of these two methods should be specified by the user. Failure is considered to occur if the maximum compression strength
attained is less than the specified load, or the specified load has not been reached before a critical defined deformation, for example,
19 mm [0.75 in.] deflection for top loaded RSC style containers.
8.3.3 Specified load will depend on the stacking load expected in storage or transportation. A method of determining compression
test requirements based on specified stacking loads is described in Appendix X6. Calculation of specified load includes the use of
a design factor (often called a Safety Factor or an Environmental Factor) to account for the loss of strength in a corrugated box
due to distribution hazards such as long-term storage, high humidity, stacking and palletizing irregularities, and rough handling.
The factor is multiplied by the known stacking load to determine the desired machine compression strength.initial compression
strength required by the box.
8.3.3.1 This initial box compression requirement is the strength required to support the anticipated load on the bottom box in a
stack considering the conditions used to calculate the safety factor, F.
8.3.3.2 This initial, target, strength is based merely on load and anticipated hazards not pre-knowledge of the materials required
or the box design to be used.
8.3.3.3 This target strength can be used to evaluate materials of construction and box structure in the box design process.
8.3.3.4 Sample boxes made with the selected materials and
...