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This is to certify that the
thesis entitled

Rule 41 - Performance Standards
Material Requirements

presented by
Mark William Holmes

has been accepted towards fulfillment
of the requirements for

. . . k .i ,
M 3 degree in Pac ag ng

 

 

Dr. James W. Goff

 

Major professor

Date____-___Eebruarx 2 , 1976

    

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ABSTRACT

RULE 41 - PERFORMANCE STANDARDS
VS. MATERIAL REQUIREMENTS

bY

Mark W. Holmes

This thesis was an attempt to delve into the issues sur-
rounding the controversy over Rule 41 of the Uniform Freight
Classifications. The controversy involves more than just
Rule 41. Carriers must, and wish to, publish the conditions
under which shipments will be accepted, a principle portion
of these conditions being packaging requirements. There are
several sets of Classifications, each with its own require-
ments, but they are basically modelled after the Uniform
Freight Classifications. Since Rule 41 can be viewed as the
"original" freight packaging requirement it has become the
focus point of a larger controversy. Since the inception of
this Rule attempts have been made to discredit the validity
of its burst requirements for determining adequate packaging,
some urging the use of alternative material requirements,
others urging the use of performance standards.

The initial step involves the theoretical aspects, to
determine the basic functions the Rule should fulfill. A
Freight Rule must be able to accurately determine the ability

of packaged products to withstand transportation hazards.

Mark W. Holmes

It should be able to allow for the differing packaging needs
of various products without unworkable complexity. Test
criteria should be simple, standard, and reproducible and
should not be biased against alternative materials. The
evaluation of any Freight Rule criteria must, overall, be in
light of the objectives of the total system, primarily least
total costs.

The functions this Rule should fulfill formed a basis

of comparison between the effects of various alternatives.

_.._._ —.—.__

 

 

 

Different material requirements varied mainly in their repro-
ducibilities and in their ability to predict damage. Material
requirements are inherently unable to account for differing
products needs. The performance of one product gives no
indication of how another product will perform in a package
of the same material. Material requirements are also biased
against new and alternative packaging materials and deters
their usage. Both the inability to account for varying needs
and the bias against alternative packaging materials can
prevent the attainment of least total system costs. It was
concluded that if a material test is to be retained as a
Freight Rule criteria the most suitable tests are edge crush
or other compression based tests.

The basic differences between material requirements
and performance standards arise because material requirements
tell how a product should be packaged and performance
standards tell how a packaged product should perform. Per-

formance standards readily account for differing product

Mark W. Holmes

needs and present no obstacles to the introduction of suit-
able alternatives to established packaging materials. While
it must be acknowledged that performance testing will un-
doubtedly become more advanced and refined in coming years
the current capabilities of performance testing are above the
minimum level necessary to make a workable Freight Rule.

It was recommended that the current packaging require—
ments of Rule 41 be replaced by performance standards, but
it was also recognized that for ;;;;;;i—;;;;;;;*;E‘may take

several years to gain the support necessary for the intro-

duction of performance requirements.

RULE 41 - PERFORMANCE STANDARDS

VS MATERIAL REQUIREMENTS

BY

aV“fi
Mark W. Holmes

A THESIS

submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Agriculture and Natural Resources,

1976

TABLE OF CONTENTS
Page

I. Introduction. . . . . . . . . . . . . . . . . . 1

II. History . . . . . . . . . . . . . . . . . . . . 4
A. Rule 41. . . . . . . . .
B. Controversy over Rule 41 . . . . . . . . 7

III. The Mullen Test . . . . . . . . . . . . . . . . 9

IV. Rule 41 . . . . . . . . . . . . . . . . . . . . 15
A. Content of Rule 41 . . . . . . . . . . . 15
B. Reasoning and Effects of Rule 41 . . .,. 16

1. Theoretical: What Freight Rul
Requirements should Do . . . . . . . 16
2. What Rule 41 Actually Does . . . . . 19

V. Sources of and Prediction of Damage . . . . . . 22
A. Reed Paper Group Project . . . . . . . . 23

B. Swedish Packaging Research Institute
Project. . . . . . . . . . . . . . . . . 25
C. Indications from Research Projects . . . 27

VI. Discussions on Possible Freight Rule
Requirements. . . . . . . . . . . . . . . . . . 30
A. Burst Test . . . . . . . . . . . . . . . 30
1. Defense of Burst Test. . . . . . . . 30
2. Specific Advantages of Burst . . . . 31
3. Specific Arguments Against
Alternatives . . . . . . . . . . . . 32
4. Disadvantages of Burst Test. . . . . 33
B. Possibilities of Performance Tests . . . 35
1. Acceptability of Performance Tests . 40
2. Workings of Performance Standards. . 43
3. Showing Compliance with Requirements 47
C. Discussions on Compression Requirements. 50

VII. Recommendations . . . . . . . . . . . . . . . . S7

I. Introduction

Packaging has been defined as ". . .the art, science,
and technology of preparing goods for transport and sa1e32."
The ideal application of packaging is, as a "means of ensuring
safe delivery of a product to the ultimate consumer, in sound
condition, at the minimum overall cost32." This minimum over-
all cost will come about, not by treating packaging as a
separate step, but by treating packaging as an inter-disci-
plinary function involved with develOpment, production,
marketing, quality control and distribution,. . .in fact,
packaging can be involved in virtually every facet of a pro-
duct, from the point of manufacture to the point of final use.
Because of the interrelationships in the system, the success
of each step must be measured relative to the entire system.
Cutting costs in one area can increase total costs, likewise
increased costs in one area can decrease total costs. Any
facet of packaging which in any way impinges on the attain-
ment of least costs for the total system is in need of change.

A major portion of many of these packaging distribution
systems is transportation by rail or motor freight. The com-
mon carriers, including express companies and air lines, as
well as railroads and motor carriers, must accept shipments
of almost any product presented them. Required by law to post
the charges for their services, the carriers have published

a multitude of books naming the conditions and fares for which

1

they will perform their services. The requirements for rail

are called, Uniform Freight Classifications, and for motor

 

freight are called National Motor Freight Classifications.

 

The freight classifications consist of two parts, one part
separates the myriad of available products by their various
characteristics, and groups those products of similar character—
istics together into classes. To use the Classifications,

a product must first be identified by its transportation
description, not merely a trade name or generic description.
The user then must choose the applicable classifications,
generally rail or motor freight, and search the Index to
Articles for the applicable classification description. For
each article, the index lists one or more item numbers. The
Classifications list the items in numerical order, giving for
each item its freight rating and various acceptable packages.
The second portion consists of the Rules, which state the
conditions under which different classes of products will

be accepted for shipment. When an item is listed as acceptable
in boxes, it means a box as defined in Rule 40, or a fibre

box meeting all the requirements of Rule 41, (or Rule 222 of

the National Motor Freight Classifications). Many items will

 

be listed as acceptable in certain numbered packages. When
referring to a fibre container, a package is a container not
meeting all the requirements of Rule 41, but is an authorized
container listed in the classifications in a section titled,

"Authorized Packages or Shipping Containers." Often a product

will be accepted for shipment in more than one type of package,

or in one of several designated packages. When confronted

with a choice, the user must determine which package best suits

his needs by analyzing costs of procurement, potential damage,

and preferential freight rates afforded some types of packaging.
In this country the burst requirements, contained in Rule

41 of the Uniform Freight Classifications, are the most widely

 

used criteria for classifying qualities of corrugated and solid
fibreboard. These requirements are used to determine if pro-
ducts are adequately packaged. Failing to comply with the
regulations can result in refusal of shipment, declined damage
claims, or increased freight rates. Since the inception of
this rule, repeated attempts have been made to discredit its
validity for determining adequate packaging. Some of these
attempts urge the replacement of the burst test with another
material test, on the grounds that other tests can be of better
use in predicting performance. Other attempts have urged
replacement of any material test with the concept of perfor-
mance tests. This analysis of the controversy over Rule 41
will evaluate both types of alternatives to Rule 41's burst
requirements to determine which alternative offers the greatest
opportunity for the entire system to achieve least total costs.
For various reasons, it is felt that the present burst regu—
lations in Rule 41 can in many situations act counter to the

achievement of least total costs for the system.

II History

A. Rule 41

The beginnings of Rule 41 date to the same times that
fibreboard began gaining acceptance as a means of packaging
for freight shipment. The first usage of corrugated in
freight shipments was in 1894, and occurred through a techni-
cality. Though the then current classifications did not allow
general use of corrugated containers, an exception to the
classifications permitted shipment of lamp chimneys in "pack-
ages", this technicality permitted corrugated containers to
enter into freight shipments. In 1903 an exception to the

Official Freight Classification permitted use of corrugated

 

containers:flmrcerealsixithe Midwest, this exception was ex-
tended to the East in 1904. Official Classification 28 give
the first official authorization of shipments in solid and
corrugated fibreboard on July 1, 1906. Packages were not
regulated by size or weight limitations, and no minimum test of
board was required, but the packages were subject to a freight
penalty of 10%. The freight penalty was the result of pressure
from wooden box interests, who were trying to curtail usage of
corrugated containers. It is important to note that Western
wooden box manufacturers and lumber companies were, and still
are, owned by railroads. In 1907 the Official Classifications
introduced specifications for thickness of fibreboard con-
tainers, imposed a 60 point weight limit, and dropped the 10%
penalty on carload lots. During the same year the Western

4

Classifications #40 Rule 14B set more detailed specifications,
including the Mullen test, as a standard of box strength. The
next year the Official Classifications adopted more detailed
specifications, including the Mullen test, and dropped the 10%
penalty on LCL shipments. In 1910, with the cooperation of
boxmakers, the Committee on Uniform classification detailed
specifications covering test requirements, weight limits, and
size limits for corrugated and solid fibreboard boxes. These
were included in the Official, Western, and Southern Classifi-
cations until 1919, when the three separate classifications

were cancelled and the Consolidated Freight Classifications

 

were introduced. Regulations for fibre boxes were included
as Rule 41.

Prior to 1912 many people, especially in the railroad
owned lumber and wooden box industry, regarded fibre containers
as inferior substitutes for wooden containers. These inter-
ests were making serious efforts at discouraging usage of
fibre containers. About 1905 wooden box interests published

a propaganda book entitled, The Wooden Box vs. the Substitute,

 

containing carefully selected photos showing seriously damaged
fibre containers, damage which was, in most cases, caused by
poor handling techniques. These efforts at curbing fibre

box usage came to a head in the "Pridham Decision." The
Pridham Company planned a fibre box plant in Los Angeles, but
discovered that although the Western Classifications had
provided for fibre containers since 1906, Western Railroad

accepted them only at "class" rates for eastbound shipments,

regardless of volume. Fibre boxes being shipped from East to
West were allowed "commodity" rates, but eastbound "commodity"
rates were applied only to wooden boxes. Since class rates are
normally about 20% higher than commodity rates, this acted as

a 20% freight penalty on fibre boxes. When the Pridham Company
asked the railroad for rates equivalent to westbound goods,

he originally got a promise for equivalent rates for fibre boxes.
Pressure from lumber and wooden box interests, formidable
financial interests at the time, caused the railroads to renege
on their promise and the Pridham Company appealed to the I.C.C.
The case finally became one where the fibre box industry and
active shippers, including Quaker Oats, Postum Cereal, and Ball
Bros., sought full acceptance of fibre containers, and the
lumber and wooden box industries sought removal of all permit-
tance of fibre boxes from freight classifications. Finally

the Commission rejected the arguments of the wooden box inter-
est and ruled there to be no transportation differences between
wooden and fibre containers and that rates be set accordingly.
The "Pridham Decision" ended the position of the fibre box as

a "substitute container."

The Consolidated Freight Classifications still exist,

 

but most functions, including Rule 41, have been taken over

by the Uniform Frieght Classifications. With only minor

 

modifications the original Rule 41 continues to regulate fibre
box usage. The most significant of these changes were the
inclusion, in 1925, of a minimum caliper for mediums, and

adoption of basis weight instead of caliper as a criteria for

facings in 1944. Specifying by basis weight, instead of caliper,

allowed the use of lower weights of kraft linerboard.

B. Controversy over Rule 41

The controversy, over whether or not burst strength forms
an adequate basis for judging relative performance character-
istics of fibreboard for regulatory purposes, has been going
on about as long as Rule 41 has been in force. A report dated
April 7, 1919, by A.J. MacKenzie, told of a project in which
they attempted to find a relationship between the performance
of boxes and the burst test of the board. They concluded the
Mullen test gave no indication of the durability of the box
as measured by the revolving drum test. Though this project
could be questioned for scientific validity, it retains in-
terest as an historical note, dating the Rule 41 controversy.

During the fifties, the puncture test was often referred
to as a possible replacement for the burst test. Puncture
was supposed to offer several advantages; the equipment is
easier to keep in calibration, it avoids the double pop pro-
blem of burst tests, and can be used to test triple-wall
board. Maltenfort defended the burst test against the puncture

20

test on the grounds that the puncture test is not sufficiently

reproducible and could not be predetermined for combined board
from properties of the liners. McKee19 concluded that although
the puncture test correlated better with damage than the burst
test, it was not enough better to be much of an improvement.

Between 1940 and 1950, there was a growing interest in

the importance of the compression strength of fibre boxes in

regard to protecting contents. One result was an attempt to
have the requirements of Rule 41 amended to include minimum
compression strength based on materials, size and shape of
boxes. There was much discussion at the "Special Docket of

the Consolidated Classification Committee on Rule 41, Fibre
Boxes" in 1946, but the effort failed because of anticipated
difficulties in enforcement. Some procedure based on com—
pression would seem to be the favorite alternative among

those writers commenting on the unsuitability of burst strength
as a basis for Rule 41.

One substantial proposal for a change in the boxmakers
certificate was put forth by Kivling. His preposal called for
each box to carry four separate ratings, one for each liner,
the medium and the adhesive. The ratings were to be alpha-
betical, with each letter standing for a different quality of
material. The various qualities would cover such things as
basic weights, stiffness, and degrees of water resistance.

If Rule 41 is to continue in a form similar to the present,
the number of possible combinations under this method would
make it far too cumbersome. But if standards for performance
testing are introduced, Kivlin's method offers a means of
standardization for the corrugated industry far more useful

than burst.

III The Mullen Test
The primary material property requirements of Rule 41 are

based on minimum burst strength (lbs/inz), the major exception
being for triple-wall board, which is based on minimum puncture
test (in.oz./in of tear). Burst testers in this country are
most commonly Mullen or Cady testers, although there have been
other American testers, including the Webb tester which was
designed for use in the field. Europeans have also developed
several burst testers, the most popular being the Schopper-Dolen
tester. Since the tester most widely associated with burst
testing is the Mullen test, the terms Mullen test and burst test
shall hereafter be used almost interchangable. The Mullen tester
was developed in 1887 by J.W. Mullen and was quickly adopted for
testing by both the paper and fabric industries. Burst was
first included as a basis for freight classification in 1907.
Burst strength has been included as a criteria for fibreboard
in the Uniform Freight Classification since its outset.

The material property requirements contained in Section 3 of
Rule 41 are given by Table 1. All of these requirements must be
complied with. If necessary to meet tests specified combined
weights of facings or component plies must be increased above
the minimum. This section also includes the following procedure
for burst testing.

Note 1- (a) Minimum test per square inch referred to

in this rule,:hiseparate descriptions of articles, or

in descriptions of package numbers, means the bursting

strength of materials hipounds per square inch, measured

by tests made with the Cady or Mullen tester. The dia-

phragm used in this tester shall be such that apressure

of 23 to 30 pounds will distend it to a height of 3/8 inch
above the diaphragm plate. A motor driven tester of

9

10

the jumbo type operating at a constant speed of
approximately 120 revolutions per minute shall
be used.

(b) In applying Cady or Mullen tests, a specimen
of the board shall be clamped firmly in the machine
to prevent slippage. If board slips during tests,
the results must be disregarded. In testing corru-
gated board, double pop tests may be disregarded.

(c) Six bursts must be made on unscored areas,

three from each side of the board. Only one burst

is permitted to fall below minimum test required.

Board failing to pass foregoing test will be accepted

if in a retest consisting of 24 bursts, 12 from each

side of board, not over 4 bursts fall below the mini-

mum test required. When individual bursts in a

series are invalidated for reasons described under

Paragraph (b), and disregarded, additional bursts

shall be made until the total number of valid bursts

required to complete the series has been secured.

Section 3 also includes procedures for puncture tests, since
puncture is used as a criteria for triple wall board. This sec-
tion also includes provisions for Referee Test Conditions, size
extensions for boxes of less than maximum weight, and multiwall
boxes with heavy duty manufacturers joints. Additional notes
deal with "Master-Pak" boxes and multiwall boxes over the maximum
weight.

The above procedures for burst testing specify diaphragm
pressure tolerance and test speed but prescribe no procedure for
compliance. Instrument variables, such as indicator calibration
or platen condition, are not mentioned, but can affect test re—
sults. Clamping pressure is left to the discretion of the oper-
ator, except that visible slippage shall be disregarded. Tappi
methods T807 and T810 give procedureszflmrburst testing, and vary

in that T807 specifies clamping of lOOpsi, and T810 clamps to

prevent slippage.

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During a burst test, as pressure is applied to the specimen,
bending and shear stresses are induced in the specimen as well
as direct tension stresses in the middle plane of the specimen
due to stretching. For thin sheets at large deflections bending
and shear are small in comparison to direct tension. Bursting
strength is primarily dependent on tensile strengths and stretches
of sheet in machine and cross directions. Relationships between
burst and other properties have received much attention. Due to
various assumptions most results are applicable only to thin
sheets of paper, not to corrugated boards. Whittsitt covered
numerous theories relating burst strength to tensile strengths
and breaking strainsl. The following formula is indicative of
these theories and is attributed to Vanden Akker.*

(l) P=(24S x45 x T)/r

P=burst strength

e=breaking strain

r=radius of orifice

T=average of machine and gross

direction tensile strength

As a good approximation, burst is proportional to the product
of average tensile strength and the square root of breaking
strain in the least extensible direction, normally machine
direction. Assuming failure occurs in the machine direction,
the strain, meaning that cross direction tensile force at

rupture will be less than maximum in the tensile test. De—

fining T as average of machine and cross direction tensile

 

*Whittsitt refers to this formula (1) and attributes it to
an unpublished work of Vanden Akker at the Institute of
Paper Chemistry in 1937-38.

13

strength fails to take this into account. Another weakness
is that burst tests involve biaxial strains while tensile
tests involve uniaxial strains. In a tensile test lateral
contractions of the specimen can occur, but cannot occur in

a burst test, so the force required to induce a given strain
in a burst test will be greater than that to induce the same
strain in a tensile test. For most purposes it is sufficient
to assume burst is proportional to tensile and square root

of breaking strain.

Proper calibration of a Mullen tester is important and
somewhat controversial, with deadweight testers normally used
in calibration it is difficult to simulate the inertial effects
causing most guage error. It is felt that electronic indi-
cator systems may offer some advantages in that they better
maintain calibration.

Rule 41 gives no requirement for clamping pressure when
performing a burst test. Vanden Akker's formula relating
burst to tensile strength indicates burst is inversely pro-
portional to the radius of curvature of the sample at rupture.
The lower the clamping pressure the greater the degree of slip
or stretch in the clamp area, causing a decrease in the radius
of curvature and hence an increase in bursting strength. As
clamping pressures increase, slippage or stretch decreases.
After the point where slippage approaches zero, further
pressure increases have little effect on results. Specifi-

cation of high clamping pressures minimizes variations in burst

14

due to variations in clamping pressure. On the other hand,
at very high pressures the flutes are crushed, and signifi-
cantly lower results are obtained. At present there is no
standardization of clamping pressure, but it seems best to
use a clamping system assuring even pressure on each sample,
such as a pneumatic or hydraulic. Results can be affected
by variation in the conditions of clamping surfaces, due to
changes in the amount of the coefficient of friction, causing
changes in the amount of slippage. Variations in the radius
of the orifice affect results by changing the radius of
curvature at rupture.

Other sources of variation come from air in the hydraulic
system, or changes in the rate of loading. Considerable vari-
ability can be gained from variations in diaphragms. There is a
diaphragm specification written into Rule 41, but there is no
published information relating this tolerance to variations
in bursting strength.2 The Mullen test also has variability
between laboratories and methods often used to check inter-
laboratory calibration are of doubtful use.6

In performing these tests it is occasionally possible to
audibly detect double-pops, especially when testing double-
wall board. Results of double-pop tests are allowed to be
discarded. Actually when testing corrugated the two facings
rarely break simultaneously, even if no double-pop is detected.
The variance lies in the time interval between ruptures, for
short intervals the difference between pops is not detectable

audibly.

15
IV Rule 41

A. Content of Rule 41

The controversy over,Ru1e 41 has centered primarily on
the burst requirement contained in Section 3, less controver-
sial are sections giving requirements for aspects of fibre-
board packaging ranging from cushioning for fragile items to
methods of closure. i

Section 1 gives rates for conforming, non-conforming,
and "other than Rule 41" boxes.

Section 2 gives provisions for use of solid and corrugated
fibreboard. Both must possess proper bending qualities and
be firmly glued together. Corrugated must have a water resis-
tant outer facing and a corrugating medium not less than .009
inch thick and weighing not less than 26 lbs/1000 sq.ft. Pro—
vision is made for hand holes, ventilation holes and perfor-
ations. Terms such as prOper bending qualities and water
resistance are defined in Section 14.

Section 4 gives regulations for the use of familiar box-
makers certificate. Each box must bear a legible certificate
bearing information from Section 3 applicable to that box,
plus the name and location of the box maker. This Section also
describes the certificates for special numbered packages for
fragile items covered in Section 5.

Section 5 gives provisions for packaging of fragile
articles including glass and earthenware. Detailed specifi-
cations provide requirements for weights, capacities, mediums,

facings and interior separators and pads.

16

Descriptions of general styles of boxes are given in
Section 6. Sections 7 and 8 deal with acceptable methods of
closing boxes, and Section 11 gives acceptable methods for
forming manufacturer's joints. The concepts contained in 5,
7, 8 and 11 are very important in assuring safe transit of
boxes, and possibly prevent more damage than the burst re-
quirements of Section 3. If other material requirements were
substituted for the burst requirements of Section 3, the re-
maining Sections of Rule 41 would remain virtually intact,
most changes being where material is specified by pounds burst.
However, if performance standards are substituted for burst
requirements, virtually all of Rule 41 will be replaced. Most
sections contain requirements attempting to assure prOper per-
formance, with performance standards this would be assured by
required tests.

Besides Rule 41, fibre board packaging is provided for
by the numbered Special Packages, or under provisions of
Rule 5. If a shipper feels he has an adequate package that is
not allowed in the above provisions, he can often arrange for

experimental shipments under the provisions of Rule 49.

B. Reasoning and Effects of Rule 41

1. Theoretical: What Freight Rule Requirements
Should do

Before it is possible to evaluate the alternatives for
freight rule requirements, it is necessary to have an under-

standing of the functions these requirements should fulfill.

17

Any freight rule requirement should be of broad applicability.
While ideally this would entail having a single set of require—
ments for different product classes, what must be avoided are
requirements stipulating exactly how each product must be
packed, the myriad of available products would make such re-
quirements unworkable. The standards set as freight rule re-
quirements would be meant to serve as general guidelines not
as packaging specifications.

Requirements that are set up must be based on a method
capable of giving accurate prediction of expectable damage.
Any test being used as a basis should be such that there be a
significant relationship between the level of the test, and
aspects of normal usage, and such that when any package fails
to give the required test results there arises serious question
of the ability of the affected package to bring its contents
to their destination in good condition. Basing requirements
on methods capable of accurate damage prediction, gives a basis
for refusing shipment for those containers not prepared to
make transportation reasonably safe and practical, and a basis
for paying damage claims in instances where damage results
from carrier negligence. Herein lies the issue which could
prevent a single set of requirements from applying to all
packages. What level of damage can be accepted, while still
calling transportation safe and practical? A damage level
completely acceptable for shipments of commercial flour or

cereal, would be unthinkable for exotic electronic equipment

18

or harsh chemicals. Before any requirements can be set, it
is necessary to determine what levels of damage are acceptable
for different product types.

Besides giving a good indication of the performance of
the container in the conditions it will meet in transportation,
test criteria should be limited and relatively easy to under-
stand. Test criteria should be limited because of the costs
of testing, and the more complex requirement are, the more
difficult the judgement of compliance becomes. Making test
criteria simple, standard, and reproducible, gives all parties
to any controversy a common standard of reference, allowing
each to verify compliance, or non-compliance, using readily
available equipment.

Criteria should be able to differentiate where pertinent
differences exist, but some controversy can evolve over which
differences are pertinent to transportation. Clearly ability
to discern differences in ability of a package to withstand
transportation hazards will be necessary, but it is not neces-
sary for freight rule requirements to differentiate material
qualities. While standardized material grades are neces-
sary for consistency, discerning these qualities is not a direct
concern of a freight rule. The direct concern of a freight
rule is the ability of packaged products to withstand trans-
portation hazards.

Evaluation of any freight rule criteria must be made in
light of the objectives of the total system, mainly, least

total costs. Shippers should be allowed to use the cheapest

19

available method of obtaining low damage. The criteria should
not prevent the usage of new material developments. Require-
ments designed so that only certain materials are able to meet
them will act in a manner restricting usage of other materials.
For any product there is a point where the costs to obtain
reductions in damage become greater than the costs of the
damage prevented. This point will not be the same for all
products. In other words, least total costs can be attained
at a higher damage level for low value products than for high
value products. Of course exact determination of these costs
is impossible, since many costs are intangible, but any criteria
able to take this concept into account will offer substantial
advantages in attaining least total costs.
2. What Rule 41 Actually Does

The actual effects of the burst requirements can be quite
different from the theoretical functions outlined above. The
freight rules, (including Rule 41) are written with the assump-
tion that packaging will take place in metal, wood, corrugated,
or fibreboard. At the time of inception of the rules this was
true, but now other alternatives have been developed, including
plastic corrugated and shrink films. The most common form of
exterior packaging is the box, by the definition of a box con-
tained in Rule 40 and 41 a box must be wood, or fibreboard,
meeting certain burst and basis weight restrictions. Regard—
less of how satisfactory they may be, the only manner by which

a shipper can use a plastic board or film outer container is

20

through an exception. Since the current phrasing of the rules
stipulates the material of which a box must be made it dis-
criminates against new package developments.

There is considerable doubt as to whether the burst re-
quirements, by themselves, are capable of determining whether
packages are adequate. The requirements, as given, do not
take into account product differences. Section 5 of Rule 41
contains additional requirements for fragile articles but even
these fail to take into account differences between fragile
articles. The result is that some products must be grossly
over packed in order to meet requirements, while others can
meet requirements to the letter, and still be inadequately
protected. Since damage claims are paid on the basis of whether
or not a package meets the requirements of Rule 41, a shipper
who has determined his product is well protected in a non-
conforming container, will be unable to collect claims on
damage, even if caused by carrier negligence.

The present requirements of Rule 41 can prevent the
achievement of least total system costs for some products.
Even if a company determines that by shrink wrapping their
canned goods, instead of using corrugated containers, they can
achieve lower material and handling costs, and equal or lower
damage levels, they cannot ship these products on a common
carrier. By requiring shipment in fibreboard the carrier pre-
vents potentially substantial savings, potential savings
which could result in lowered prices, or averted price in-

creases. If a company finds its Product sustains almost

21

zero damage in a container made of board equivalent to 125 1b.
test, but the size and weight of the container require 200 lb.
test board to meet the regulations in Rule 41, he can avoid
the potential problems of ignoring Rule 41 only at an increased
cost to himself. In either case, acting in accordance with
Rule 41 results in additional costs to the concerned product
system.

One of the requirements of a test, forming the basis of
a freight rule, is good reproducibility. Because of uncon-
trolled variations in machines and nonstandardized procedures
covered in an earlier section, the Mullen test has a reproduc-
ibility of only 20%, or worse,a very marginal performance when
used for purposes requiring good reproducibility. Additionally,
the Mullen test is unable to detect some differences pertinent
to the ability of packaged products to withstand transportation
hazards. A fair correlation can be shown between level of
burst and performance for one package, but this offers no
guarantee of correlation between the performance for a certain
burst level with that package, and the performance of a
different package made from board of the same burst test.
Ideally, a test criteria for a freight rule should be such
that any package, giving a certain result in the test, can be

expected to give approximately the same performance in actual

conditions.

V Sources of and Prediction of Damage
As stated under the theoretical requirements for a freight
rule, any tests being considered should give a good indication
of the performance of the fabricated container under the con-
ditions it will meet in the field. In order to determine which
tests give results best indicating performance, it is necessary
to have data in two areas:
1) what are the types and causes of damage being
experienced
2) which tests give results having high correlation
between predicted performance and actual per-
formance, based on observation.
It is often stated that damage in shipping comes from three
primary sources: 1) impact, 2) stacking, and 3) vibration.
Damage resulting from stacking occurs primarily in warehouses
where pallet loads are stacked three and four high. With
parcel post shipments the worst damage problem is with packages
breaking open on impact.* In establishing requirements to
assure that packages are adequately protected against hazards
they will encounter during transportation, a freight rule need
only be directly concerned with those hazards to be encountered
during transportation. The freight rule should require a
package to withstand the forces of impact and vibration to a

degree which can be reasonably expected to occur, but except

for the degree that resistance properties are interrelated,

 

* From a conversation with Dr. Goff, Director, School of
Packaging, MSU.
22

23

it need not assure performance under conditions not present
in shipping, i.e., warehouse stacking. Those companys using
warehouse stacking may incorporate additional standards, if
they desire, but those not using warehouses should not be
required to protect against situations to which they will not
be subjecting their products.

The aim sometimes stated for laboratory testing, is the
simulation of some ill-defined, "conditions in the field,"
in effect, to simulate the forces present in impact, stacking
and vibration, in an attempt to achieve the same damage levels
and types. The data on damage levels and types are based on
field trials, whose results are the average of widely varying
damage levels from a large number of samples. A better aim
for lab testing, other than simulation, is, after determining
which container styles, materials, and material properties
offer protection, to differentiate between these qualities
where differences exist.

Writings on research projects, seeking to determine
correlations between test results and damage during shipment
trials for boxes of various grades of corrugated, were found
to give results pertinent to the issue of a test basis for
Rule 41. One of these was performed by the Reed Paper Group

10

of England , and the other by the Swedish Packaging Research

Institutezs.

A. Reed Paper Group Project
Experiments were performed by the Reed Paper Group, to

correlate damage levels from field trials for rail and truck,

24

to test results obtained from various lab tests. They tested
cases in two separate groups. One group was filled with cans
to represent cases whose products support most of the load.
The other group was filled with cartons, representing products
whose cases must bear a high degree of the load. They tested
cases of eight different qualities, based on various grades of
liners and medium. Their primary interest was differentiating
damage levels to the contents, not to the containers. In the
carton field trials, the road tests consisted of full trailer
loads transported across London, stored for a week than trans-
ported to a factory, a total distance of 80 miles. The rail
trial consisted of a full load taken about 80 miles, with a
final short journey in a delivery van of mixed goods. The can
trials consisted of pallet loads, which were stored for two
weeks, then shipped 250 miles, half of the pallets by rail and
half by truck.

Damage coefficients were computed for each container grade
for cartons and cans. These damage coefficients were corre-
lated with data obtained from various laboratory tests, in-
cluding compression, drop tests, incline impact, flat crash,
burst, puncture and vibration. For cases carrying cartons,
the best correlation with performance, as indicated by degree
of carton damage, was for drop tests, followed closely by
compression tests. These two tests gave the only good corre-
lations with damage. Field test damage to cans had low levels;
and there were no significant differences in damage levels

to the cans between cases of different qualities, but there

25

were significant differences in the amounts of damage sustained
by the cases. This indicates that cans probably do not need a
container affording protection as much as they need a means to
be held tOgether. Laboratory tests for cases of cans were
therefore restricted to those testing the ability of the board
to resist tearing and to contain the cans. The only good cor-
relation between laboratory results and field trials was for
burst tests. It was not noted which tests were included, but
it most likely excluded compression tests and edge crush tests,
whether or not drop tests were included was impossible to discern.

B. Swedish Packaging Research Insititute Project

The Swedish Packaging Research Institute Project25 was
set up primarily to determine which corrugated board properties
are most significant for determining the level of protection
the container affords the packaged product. They chose three
different classes of products; products that can stand limited
loads, represented by cartons; products that can withstand
pressure and impact but exert destructive forces on packages,
represented by vacuum cleaners. They chose twelve grades of
corrugated based on different values of burst, edge crush,
puncture and flat crush. Four grades were chosen to keep the
bursting strength relatively constant while other properties
varied and four were chosen to keep flat crush relatively
constant while the other prOperties varied. The final four
were chosen to correspond to commercial corrugated. Transport

trials consisted of three seasonal shipments to each of seven

26

countries to assure that the trial shipments were subject to
all types of encounterable hazards. The destination countries
included the United States and six continental countries. Upon
receipt all containers were checked for damage with regard to
type, location, and extent. Analysis of the damage showed, as
expected, widely varying damage levels between the routes, but
differences between the various grades were the same regardless
of the destination.* These high correlations allowed the
various data to be combined into average values.

Six material tests; compression resistance, bending stiff-
ness, bursting strength, puncture, edge crush, and flat crush,
were chosen for detailed study because of their pertinence to
the investigation. These six material prOperties were analyzed
to see which were dependent and which were independent. Com-
pression resistance, edge crush, and bending stiffness showed
high correlation with each other and were adjudged dependent
variables. Further analysis in this project was restricted
to edge crush, puncture, burst, and flat crush.

Analysis to correlate damage to material properties
assumed the following relationship between material properties
and amount of damage.

_ . a 8. y 6
(2) Y — k x 2 x3

Y = amount of damage
k = constant
x1 = bursting strength - kp/cm2

 

*With a 95% probability

27

.qa a .munufiumcH noncommm wawwmxomm cmfinm3m .uommoum :uummmmm
..o .comGLOH .:.<.m.s can moousm ou mmxom pumom pmumwsuuou :uwa manage uuodmcmuez ”mousom

 

 

 

oo.H Hw.o 55.0 mo.o en.o om.o smouo umHm
oo.H Nw.o H¢.o cm.o ma.o nmsuu mwtm
oo.H cm.o mm.o mn.o muauucsm
oo.H qm.o mm.o sumcmuum meanmusm
oo.H gm.o mmwcmWHum wcwpawm
oo.H mocmumwmmm cowmmmudaou
nmsuo nwsuo Suwamuum mmmcwmeum measumwmmm
umam mmpm musuocsm wafiumusm wcwccmm coamwoudaoo
mucmaoawwmoo coaumamuuoo Suumdoum Hmwumumz

mmfiuumdoum Hmfiumumz mo mcouumamuuoo "N mance

28

x
ll

2 puncture - kp/cm

X
ll

3 edge crush - kp/cm
2

X
I

4 - flat crush - kp/cm
a+6 = exponents
Multiple regression analysis was performed to determine
the exponents. Since the object is to reduce Y to as low a
value as possible the property with the most negative exponent
can be considered most important as an indication of perfor-
mance, a positive value would indicate a property that allows
more damage as it increases. These analyses were performed
for the various seasonal shipments, type of damage, and type
of product. Overall it was concluded that the most important
measure of protective capacity of corrugated was edge crush,
and hence indicating importance of compression resistance and
bending stiffness. Also giving some degree of measure of
protective capacity for both cartons and cans was the bursting
test. Puncture was deemed to also be an important quality
with regard to products similar to cartons, but proved a poor
indication of container quality for tin cans. It was deter—
mined that in all cases flat crush should not fall below a
minimal level.They strongly emphasized that no single material
property was of decisive importance and that it is necessary
to have a thorough knowledge of packaged products to properly
select corrugated board boxes.

C. Indications From Research Projects

Several interesting points can be derived from these

two projects.

29

1) Both projects concluded that of the material properties
tested, compression and compression type tests gave the best
overall indications of performance.

2) The situation which included the drop test, a performance
test, gave a higher correlation with actual performance than
any individual material test.

3) The project by the Swedish Packaging Research Institute
concluded that performance is based on a combination of pro-
perties, and that even though some properties are shown to

be better indicators of performance, none are of decisive im-
portance in all situations. The combination giving best per-
formance varies, since each product exhibits different character—
istics. The relative importances they found were determined
for overall damage levels, the importance of each property
was found to change if particular types of damage were to be

avoided.

VI. Discussions on Possible Freight Rule Requirements

A. Burst Test

1. Defense of the Burst Test
In this section it is sought only to present arguments

which have been offered in defense of bursting strength as
a freight rule requirement. The validity of these arguments
will not be questioned in this section, but will be scrutinized
in later sections on performance tests, and compression tests.
The first few of these positions actually could be applied to
any material property to be used as a basis for a freight rule.

A freight rule should be written so as to apply to all
containers offered for shipment, therefore, containing only
specifications of broad general nature, such that when the
test results do not meet the requirements, there arises serious
question of the ability of the affected package to bring its
contents to their destination in good condition. Keeping re-
quirements of a broad general nature precludes the possibility
of making a freight rule an encyclopedia of packaging specifi-
cations, covering all aspects and situations.

A freight rule should not assure the safe delivery of
all packages, but should provide a degree of protection
assuring safe delivery of the broad group of easily handled
products, and give basis for refusing for shipment those con-
tainers not so prepared as to make transportation reasonably
safe and practical. Products vary widely in their need for

30

31

protection; a requirement strong enough to assure safe-delivery
of all products would result in great waste of costly materials,
since most products would be over packaged.
2. Specific Advantages of Burst
The defenders of the burst test as a freight rule

criteria, most notably Maltenfort, have pointed out several
characteristics, which they feel make the burst test a more
advantageous criteria, for a freight rule, than other tests.

First, they claim that the burst test is the only test
that can adequately assure a predetermined strength in the
combined board, by properties measurable at the mill on pre-
combined materialszo. By measuring the burst strength of the
liners, and adding the strength of the liner after adjusting
for the take up factor, the burst strength of the combined
board can be predicted, with good accuracy. This offers
advantages over tests such as the puncture, for which no
method is known to assure a given test level before the mater-
ials are fabricated.

Secondly, the burst test can be run on damaged boxes,
with results very close to that of the original boardzo.
Since compliance to the Rule is questioned, most frequently,
upon the occurance of damage in transit, and the only avail-
able information for judging compliance are the damaged box
and its contents, a test which need not be run on factory
fresh boxes or materials offers distinct advantages.

Thirdly, most strength properties of board diminish with

time after fabrication. Puncture levels, or compression

32

strengths of board which has been stored for 6 months will be
significantly less than that of the initial levels. If com-
pression were used as a criteria, it could be difficult to
determine if board, which had been in storage, had originally
complied with requirements. Conversely,burst levels are main-
tained much better than other properties over time, making it
immensely simpler to determine if questioned board had origi-
nally complied with requirements.

3. Specific Arguments Against Alternatives

In addition to pointing out specific advantages of
the burst test, defenders have pointed out specific disadvant-
ages of its principlemalternatives. A major argument offered
against either compression or performance tests, is that
properties reflected by these tests are properties of the
fabricated container not of the material itself21. In testing
compliance with burst requirements the test needn't be run on
every box style. Since several box styles are run at the same
time, it is only necessary to test each run, testing compliance
to compression, or performance tests would require the testing
of each different box style produced. In addition to requiring
more testing, the testing involved for compression or perfor-
mance tests is more complex, consequently establishing com-
pliance for either of these alternatives could prove consider—
ably more than checking compliance for burst tests. Maltenfort
also claims most products will arrive in good condition packed
in boxes which would not be in compliance with compression

standards7. It was claimed that since meeting these

33

compression standards would have entailed additional expense
where it was not required, these standards would result in
considerable overpacking, and consequential waste. It should
be noted that no statement was made to point out the compres-
sion standards used, or how far out of compliance the boxes
were.

4. Disadvantages of Burst Tests

In opposition to the claimed advantages of the burst
test presented above, this test also has several widely recog—
nized disadvantages. The first of these is the Mullen tesfls;
inadequacies for testing multiwall board. The ability of this
test to measure strength properties of triple wall board is of
such a low magnitude that requirements for this material are
based on the puncture test. The inabilities of the burst test
in testing triple wall board lie in two areas. First, the
strength of this material is outside the range testable by
most burst testers. Secondly, even if an available tester is
capable of providing the pressure necessary to burst seven
layers of material, it is exceedingly difficult to get them
to burst simultaneously, a phenomena referred to as "double-
pops". This double-pop problem plagues testing of double wall
board, even though the burst test is retained for double wall
requirements. The burst test is, therefore, virtually in-
capable of providing standards for multiwall board. This pro-
blem places the Mullen test at a disadvantage with any desire

to establish one set of requirements applying to all situations.

34

A second problem associated with the Mullen test is the
equipment. As discussed earlier, the equipment must be care-
fully calibrated to achieve any level of reproducibility, and
there are several factors hindering the maintenance of closely
correlated calibration from one machine to another. Since
this maintenance of calibration is difficult, it often could
be done inadequately. The level of reproducibility of the
Mullen test, under the best conditions, assuming here that
tests to determine the reproducibility are performed on well
calibrated machines, brings doubt to the capability of the
test in assuring that two fabricators, applying the same
ratings to their boards, will actually be producing board of
the same strength. If, in fact, the testers are not well
calibrated the situation can only worsen.

A third and major weakness of the Mullen test is that
the burst strength is independent of the quality of fabrica-
tion whereas the quality, strength, and performance character-
istics of corrugated are closely tied to the quality of
fabrication. The bursting strength of a sample of corrugated
is equal to the sum of the strengths of the liners, plus an
increment for the medium. No provision is made for the
quality of the fluting or glue, either of which can affect
final strength and performance characteristics of corrugated.

A fourth disadvantage of the burst test is somewhat
interrelated with its inability to account for variance in

fabrication. The burst test, by itself, is not capable of

35

accurately predicting performance. Even the requirements in
Rule 41 take this into account in setting guidelines for
closing packages and forming manufacturer's joints. All other
things equal, burst strength can give an adequate correlation
with performance. In actual situations, though, all other
things are not equal, boxes do not all receive like qualities
of fabrication, set-up, and closing. Products do not share
like characteristics. The high degree of independence shown
between various material properties indicates that two samples,
with identical bursting strengths, may not have the same
actual strengths. The burst test may be able to give some
measure of relative performance within one box style and
product, but becomes wholly inadequate for predicting actual
performance, especially if it is desired to achieve like
levels of performance for a range of products.

B. Possibilities of Performance Tests

If a freight rule requirement is based upon a material
property, such as burst, it cannot be expected to assure
safe delivery of all packages, without resulting in a great
waste of materials. A broadly applicable material property
specification attempts to provide a degree of protection
assuring safe delivery of some non-existant "average" product,
on the assumption that there exists a single, measurable
prOperty offering a high correlation with the performance of
a fabricated container. Real-life works not so smoothly,

the measure of the strength of a fabricated container is

36

dependent on several material properties, each contributing to
a different degree, as well as the fabrication of the board
and container. Additionally, factors unrelated to the con-
tainer's material contribute to final performance. Since pro-
ducts need protection from different forces in different
degrees, the product to be placed within the container has a
large influence on container performance. Even the orien-
tation of the product within the container can influence

final performance. For cartons, compression strength is
generally considered greatest when cartons are stacked up-
right, but in addition to influencing compression, a study at
Pillsbury indicates that the orientation of cartons within a
case can also influence resistance to damage from impact.29
Regulating containers, on the basis of a material property,
cannot take into account factors influencing performance
which are unrelated to the container itself. Material re-
quirements basically dictate how products are to be packaged,
and are inherently incapable of retaining generality, if they
are to account for the individual needs of products. On the
other hand, performance standards do not dictate how products
are to be packaged, but rather, dictate what a package in
general is expected to do. A package meeting performance
standards automatically accounts for the individuality of

the product. Allowing package strength to vary with the needs

of the product will eliminate "forced" overpackaging, and

consequentialwaste of materials.

37

In addition to eliminating the overpackaging, frequently
necessary if one is to adhere to present requirements, per-
formance standards will halt discrimination against new pack-
aging materials. Unless one is shipping under the provisions
of Rule 49, a box must be either wood or fibreboard to meet
the specified material requirements. At the time the rules
were written, there weren't suitable alternatives, with the
possible exception of metal containers or paper sacks. In the
last few years, the availability of suitable packaging materials
has broadened. Plastic corrugated, shrink wrapping, and foam
packages are all available, and, in some situations, can re-
sult in lowered packaging costs, lowered damage levels, or
both. But, unless the requirements for a package contained

in the Uniform Freight Classifications are changed, these,

 

and other developments can be permitted only as exceptions,

and at the discretion of the Committee. Conversely, under

the auspices of performance standards, any new packaging
material could be accepted for shipment, providing it is

shown to provide the level of performance required for the con-
cerned application.

Ideally, the Uniform Freight Classifications should allow

 

the Optimum package for each product. Though the achievement
of an Optimum situation cannot be realistically expected in

all situations, the following procedures, if followed, would
result in a package approaching the optimum for each product:

1) For each product it should be determined, which of

38

the external forces it may be subjected to can damage the
product, or hinder prOper functioning of the container.

2) The type and severity of the damage caused by the
various external forces should be determined.

3) The destructive forces exerted on the container, by
the product, should be known.

4) The properties of the alternative materials, and
material combinations, must be analyzed, to determine the
degree to which they protect against the various destructive
forces.

5) For each product, an. understanding of the trade-off
curves between damage costs and packaging costs should be
achieved.

6) Finally, for each product, the container should be
of the material combination giving the amount of protection
against the forces to which it and its product are susceptible,
offering the best balance between packaging costs and damage
costs.

These six steps will be basically followed by any company
attempting to minimize their packaging costs. Because of the
nature of the transportation and distribution network, it is
not quite possible to gain a perfect understanding of the
forces acting on any certain package. While the exact forces
acting on any single shipment cannot be predicted, the range
of forces to which the shipment could be exposed is pretty

well understood. If a product is susceptable to damage from

39

impact, the level of force at which damage becomes apparent
should be known; if a product can be damaged by vibration,
the frequency range liable to cause damage should be deter—
mined. The type, and severity of damage by different forces
becomes petinent in a case where two different forces can
damage a product, if impact can render the product unsalable,
but vibration only scuffs the carton, priority should be
placed on eliminating the most severe damage. Knowing the
forces exerted by the product on the container is important
with products such as books, which are known to create
particular problems.

These first three steps will not be much affected by any
requirements in the Classifications. Companies should analyze
potential hazards the same, packaging will be subjected to
the same shipping hazards if it must adhere to material pro-
perty requirements as it will if it must adhere to performance
requirements. The difference between the two types of re-
quirements arises in step 4. If a freight rule is based on a
material requirement (burst strength), the packager's analysis
of potential materials is limited to those capable of meeting
the requirement (fibreboard). On the other hand, under per-
formance requirements, which do not specify a material type,
the analysis of alternative materials is not limited to
certain materials. With the present burst requirements, if
the material offering the least total cost desired in step 6,

is not fibreboard, the shipper is prevented from achieving his

40

least cost figure, with no gain in utility whatever. Since

performance tests do not restrict the materials analyzed in

step 4, the least total cost desired in step 6, is much more
likely to be achieved.

Step 5 contains the key to deciding what levels of pro-
tection are desired. In most cases, a company will not be
interested in increasing material costs by 3cents a unit to
eliminate damage costs of 2 cents per unit. Actual packaging
costs and damage costs are easily determined, indirect costs,
such as loss of consumer confidence, are harder to determine.
Companies will not always be able to chose damage levels solely
on the basis of packaging costs. With shipments of hazardous
materials any damage whatever is unacceptable.

l. Acceptability of Performance Tests

Though the primary present requirements for boxes are
the burst requirements of Rule 41, there are numerous prece-
dents for performance tests. The Uniform Classification
Committee currently accepts performance test data in support
of test shipment permit applications for non-complying boxes.
Various performance tests, most frequently drop tests, are
included in the specification for packages for many hazardous
articles, and are included for some packages in Rules 40, 41
and 51. Performance tests are spelled out for a number of
theNumberedPackage Series. Whether specified by performance
tests or not, the theory behind the special numbered packages
is performance, these packages prove adequate even though

they do not meet other requirements. In each of the instances

41

outlined above, performance tests are included in specifi-
cations, through the recognition that for the concerned
application, burst strength alone cannot and does not assure
adequate container strength.

All of the advantages of performance test previously
discussed are under the assumption of the existence of suitable
methods of performance testing. All prior arguments remain
theoretical in the absence of suitable testing methods. Per-
formance tests do not have to simulate exactly conditions in
distribution, but instead, should indicate the performance
of each potential package for a product, relative to the
alternative packages for that product. Even though exact
simulation of the distribution environment is not expected,
the test used must indicate resistance to potentially damaging
forces. If several different hazards are potentially damaging,
it is possible several tests may be needed. Much doubt of
performance testing arises through questions of the ability
of present methods to indicate resistance to actual forces.
Some of the earlier rough handling tests, such as the rotating
drum test, the incline impact or vibration tests such as ASTM
D-999-68(l973),do have questionable or limited applicability.
The rotating drum test does not correlate well with any actual
hazards. The incline impact was designed to simulate shocks
occuring in boxcars, particularly from impacts due to humping,
but, because of dissimilarities between the shocks produced

by rail impacts and test machines, or between two different

42

test machines, this test does not approach any sort of simula-
tion to humping shocks. The vibrators designed for ASTM
vibration tests are capable Of bounce tests, but lack the
frequency ranges necessary for determining resonance points.
In spite Of the limitations Of many tests, there are tests
and equipment capable Of indicating performance under various
situations. These are covered in depth in Henzi's survey Of
methods.30 With the development Of programmable shock testers
and more sophisticated vibration tests, along with the classic
rough handling test, the drop test, and several specialized
test, performance tests cannot be Opposed on the grounds Of
inadequacy.

DrOp tests provide an interesting point in testing, they
are probably the earliest form of performance testing, yet
remain one Of the most reliable. The Reed Paper Group's

experiments10

showed drOp tests tO give the highest corre-
lation with actual performance Of any commonly used lab test.
J.C. Penney CO. has develOped a testing procedure, based mainly
on drOp tests, which has cut damage levels to considerably
less than one percent, even on fragile articles.31 Moreover
drop tests are simple and inexpensive tO conduct.

Even though methods and equipment capable Of accurate
performance tests are available, it will still probably take
time for them tO become widely adopted. First, since perfor-

mance tests will no longer require fibreboard packaging, con-

siderable Opposition can be expected from fibreboard box

43

interests, in the same manner that wooden box interests
Opposed the acceptance Of fibreboard boxes. Secondly, test
procedures and conditions need tO be carefully standardized.
Standardized procedures must be worded carefully, since
frequently particular product characteristics determine proper
test procedures, such as placement Of accelerameters for

shock and vibration testing, or determining the face or corner
Of a container most likely tO damage the product during impact.
In order to simplify requirements test procedures will have

tO rely on the ability Of manufacturers tO determine weak
points Of their products. As it is, there will be resistance
from manufacturers not wishing tO purchase additional test
equipment or testing services, even though, in most cases,
costs could be cut in the long run. Probably the biggest
Obstacle to the acceptance Of performance requirements is the
resistance to change, unless a manufacturer is aware Of
specific applications in which performance requirements could
save money, they would prefer to leave well enough alone.

It will take time for performance standards tO gain stronger

support and wider acceptance.

2. Workings Of Performance Standards

Discussion Of performance tests, so far, has centered
primarily on their suitability; more than just this knowledge
is necessary before implementing freight requirements. Per—
formance standards must be written with the proper Objectives

in mind. It is not sufficient merely to seek minimized damage

44

and packaging costs, it is the total cost Of the packaging-
transportation function which should be minimized. While
the packaging-transportation function does add considerable
economic value tO products through time-place utility, the
amount Of additional value gained is inversely affected by
the costs Of this function. The costs involved in packaging—
transportation function include more than just damage costs
and material costs. Also Of concern to carriers and users
are costs occuring due tO testing, the inspections required
to determine damage, litigation when responsibility for loss
is not clear, and freight bills. When carriers are setting
up freight regulations, their direct concern will be to
minimize their costs Of moving freight and handling claims.
They must bear in mind that their users also are attempting
to minimize costs, and therefore freight regulations should
contain ample leeway for individual firms to minimize their
costs.

Below is included one possible method Of including per-
formance tests in freight regulations. This method utilizes
a combination Of rates, testing levels, and liability levels
allowing each firm to chose the combination Offering them
the least total costs. This is meant as a simplified model
involving only two levels, because the wide variety Of pro-
ducts create wide ranges Of need, the actual application Of
performance tests tO freight requirements may have to involve

more specialized catagories.

45

1) Level one would involve reduced claims liability for
the carriers, and reduced rates for users. Minimum test
levles for level one would be set up tO assure that the pack-
age itself will not fail, spilling product or creating undo
hazards for other packages, equipment, or labor. The direct
concern will not be prevention Of damage to the product itself.
A likely candidate for level one testing would be a rough
handling test such as drop testing. Because products shipped
under level one could be more susceptable to damage, they
would be accepted for shipment at a reduced liability level.
The carrier would retain liability for most catagories Of
loss, theft, or delay in shipment, but unless gross negligence
is shown, the carrier will not be liable for product damage.
In return for accepting reduced liability, the user would
receive reduced freight rates.

2) Level two would couple higher freight rates than
level one, with more complete claims liability. Testing
involved for level two would be full range testing including
shock and vibration tests as well as rough handling tests.

The more extensive test program for level two assures that,
not only is product unlikely to spill from its container

or pose hazards to other packages, equipment or labor, but
also is unlikely to sustain damage within its package. A
product-package meeting the requirements Of level two could
be assumed tO Offer ample protection against foreseeable
hazards, therefore, when damage does occur, the carrier is

liable. In return for accepting greater liability levels,

46

the carriers would receive higher freight rates.

The lower freight rates for level one can be Offered by
the carriers, primarily, through reductions in the costs Of
handling liability claims: specifically, the costs Of liti-
gation, inspection, payments for damage and insurance. This
same level is potentially attractive tO companies who compute
that the savings in freight bills and claims handling will
more than Offset the absorbed damage losses. Level two also
Offers economic attractions. The package testing required
for level two is better able tO determine Optimal packaging
for a particular product than tests for level one. Because
packages meeting the requirements Of level two will experience
minimal damage, the costs inherent in claims handling will be
reduced. Level two testing also minimizes the risk to carriers,
that they will be paying claims for damage whose actual cause
was inadequate packaging, not improper handling.

It is important to note that the test levels required
under levels one and two are minimum levels, any company
wishing to implement more exacting standards for its own
products, will be free tO do so. The most Obvious application
Of this would be where a firm accepts the reduced rates and
carrier liability Of level one, but also uses full range
testing tO minimize damages. For some products, such as
cartons or tin cans, the tests required for level one, may
be able tO dO an adequate job Of determining product pro-

tection. For other products, such as electronic equipment,

47

level one testing may assure the carrier he will not experience
undue hazards in handling the product, but are not apt tO
assure the shipper his product will not suffer damage within
the container.

There is a potential problem with level one reducing
carrier liability for damage. Since carriers would no longer
face direct costs from damage their incentive for maintaining
damage reducing handling procedures is reduced.

Another Option Open to shippers is, tO accept limited
liability on return for reduced rates, then in turn, purchase
insurance to cover losses for which the carrier is no longer
liable. The nature Of insurance companies being as it is,
firms employing full range testing would pay lower premiums
than those employing limited testing.

In most cases, product packages will not be required to
be tested at a certain level, since only the firm itself has
adequate information on its product to determine a cost min-
imizing approach. Product packages, which would upon failure
create extreme hazards tO other products, equipment, or labor,

may have tO be required tO undergo more extensive test levels.

3. Showing Compliance with Requirements

In addition to the design Of performance standards,
concern must be also granted to the manner in which compliance
will be shown. The major problem arising in this area is
that performance tests provide nothing a shipper can directly

translate into the material specifications suppliers require.

48

The parties concerned with packaging materials can be divided
into three groups, suppliers, users, and carriers, each Of
which has different concerns toward the materials. Under
Performance standards carriers primary concern with materials
should be whether they impart adequate performance to the
package. In most cases, carriers should have no direct con-
cern with the material specifications Of the packages they
handle. The direct concern Of suppliers lies in imparting to
materials those qualities users have specified, any concern
shown by suppliers toward performance Of individual containers,
would arise through their desire for good customer relations.
The users will occupy a position directly between carriers

and suppliers. They must design packages that can provide the
performance required by carriers, and be translated into the
material specifications needed by suppliers. Performance
standards will make little change in the concerns Of suppliers,
they do and will try to meet the specifications Of their
customers. Most users presently make efforts to design
packages with adequate performance, if carriers switch tO
performance standards, users design processes will be effected
in two ways, they no longer have to act within the constraints
Of material requirements, and the performance levels and tests
utilized will be uniform among the various firms. To show
that a package design complies with requirements, a firm will

need to show that the material specifications for that design

49

consistantly provide adequate performance for the product

and package. TO show that an individual package complies
with performance standards, a firm must show that, not only
does the package, as specified, provide required performance,
but also that the package itself meets the specifications.
Problems in showing specifications will consistently provide
performance, can arise with materials such as corrugated,
especially if it is attempted tO specify it by a single
material prOperty. The more complete the specification drawn
up, the better the chance that materials such as corrugated
will provide performances as consistent as materials such as
plastics or metals. It is immensely easier to impart uniform
properties to plastics or metals so firms using these will
not have the same problems showing that specifications provide
consistant performance that corrugated users face.

Once it has been established that the materials, as
specified, will afford adequate protection to the packaged
product, most subsequent orders need only be tested for
compliance tO specifications, requiring less expensive testing
than necessary to recheck performance Of filled packages.
Users will Of course, be expected to occasionally retest
performance, with the most frequent retesting being performed
for the materials showing the least uniformity. In situations
where compliance is in question, the shipper will merely have
to show evidence that the package, as specified, complies

with requirements, and the package, as constructed, complies

50

with specifications. TO discourage attempts at shipping non-
complying packages, carriers should impose penalties, such as
freight penalties and liability for any costs incurred by

the carrier because Of the non-complying packages.

With the adoption Of performance testing as a freight
rule requirement, the classic manufacturers stamp would become
archaic. It would no longer be useful from the point Of view
Of the carrier tO identify grades Of materials, but some
method Of identity should be required to facilitate procedures
in case Of questioned compliance. Such identity should include
the manufacturers name and location, and possibly a date and
batch or order number tO provide linkage between packages
and test data. Even though grading Of materials would not
be required explicitly by the freight rules, some kind of
standardized grading would Offer many advantages to suppliers
and users, and for materials where no adequate grading system

now exists, it should be encouraged that one be adopted.

C. Discussions on Compression Requirements

Even though it is felt that performance tests Offer a
more adequate basis for freight requirements than the current
burst and related material requirements, discussions on the
advantages Of Compression Standards over burst standards as
a material strength requirement are included also. These
discussions are included primarily for two reasons:

1) There is, at present, inadequate support for the

implementation Of performance requirements. Part Of the

51

extent Of support is due tO the lack Of understanding Of

the advantages Offered, part is also due to the opposition Of
certain special interest groups. Whatever the case, it is
likely that some kind Of material requirement will be in
effect for some time.

2) Even after the adoption Of performance requirements,
some material requirement could be retained in an either/or
manner, for shipments whose size or value does not warrent
testing. Inclusion of alternative material requirements
could also eliminate Opposition from shippers who, for some
reason, dO not wish to use performance testing.

It is felt, that if some form Of material requirements
are to be retained, some method, based on compression is a
more logical choice because Of several inherent advantages

over bursting strength. Tests by the Reed Paper Group10

25 Offer evidence

and the Swedish Packaging Research Institute
that compression-type tests provide better correlation with
performance than bursting strength. Measurement Of compres-
sion-type properties also is affected by variables introduced
during fabrication, variables which can significantly affect
the final performance of the package. Bursting strength is

not affected by the quality of fabrication, and can be computed
directly from the bursting strengths Of the outer liners,
making this test incapable Of predicting changes in perfor—
mance due to differing qualities Of fabrication.

One Of the primary arguments against compression-type

requirements is that, as commonly measured, compression is a

52

property Of the fabricated container, not Of the material
itse1f41. It is envisioned that meeting a compression
requirement would entail the testing of each box style or
each run, and hence, would be prohibitively expensive.
Measuring the compression strengths Of set-up boxes also does
not provide a unit Of comparison between different qualities
Of board. Some unit Of comparison between qualities is
necessary for requirements based on a material property. A
compression-type requirement need not be based on compression
measured from the completed box. One alternative is, to
simply use the edge crush strength, which has been shown to
be highly correlated with compression strength.25 A second
alternative would be to compare compression strengths Of
standard sized boxes. A third alternative would involve the
computation Of compression strength from other properties.
There have been several theories advanced on the computation
Of compression strength from material properties, probably
the most accurate Of which is the exponential method,

advanced by McKee14 and Buchananlz:

where: (l) P= n Pm h15 z8
P= total compression strength
Pm: edge crush strength
h= caliper
z= perimeter
n= a constant, varying with the

units desired and the method
Of measuring edge crush.

TO Obtain a unit Of comparison between grades, the term for
perimeter is dropped, giving a measure Of compression/unit

length:

53

where: (2) = n, thk

Pu
Pu= compression/unit length
Since total compression varies with the square root Of
perimeter, the differences between the utilization Of strength
must be accounted for during the writing Of requirements, by
calling for greater strength/unit for boxes Of larger perimeters.
Maltenfort and Kellicutt also have developed theories for
computing compression from material propertiesl3'31. These
theories, as well as exponential theory Of McKee and Buchanan,
were analyzed, using data developed by Mirasolls, comparing
computed compression with measured compression for six differ-
ent perimeters. Figures, computed from Maltenfort's and
Kellicutts formulas show a greater range in results, (comparing
the ratio Of theoretical compression to measured compression
for differing perimeters), but also show a definite trend
toward less accuracy as perimeters increased. The McKee and
Buchanan formulas showed considerably less variation, with
the existing variation being random. Mirasol's data showed
McKee's formula to give results ranging from 70% tO 73% Of
measured compression, results varying almost by a constant.
When using McKee's formula, Mirasol used the same constant
used by McKee, but failed tO realize its source. McKee
determined the constant by regressional analysis on data
Obtained with his method Of determining edge crush. Mirasol

used the same constant, but a different method Of determining

edge crush. Implementation Of any requirements based on

54

formulas (l) or (2) will necessitate the computation Of
constants (n,n,) consistant with a standardized method Of
computing edge crush (pm).

One Of the advantages Often cited for burst is, it is
the only test which can be run at the mill, on pre-combined
materials, tO estimate a predetermined strength in the com-
bined board. Edge crush can also be estimated from proper-
ties Of the precombined board by the following formula:

where: (3) ECT=: RC'Ifliners) + a ° RCTdr'lutincj
RCT= ring crush test level
ECT= edge crush level
a= constant (or take up factor)
depending on flute size
For either burst or edge crush, it must be recognized that
the estimations have inherent inaccuracies.

Other advantages cited for bursting strength are that
it can be measured on damaged boxes, and that it maintains
its level better over time. It is known that the real
strength Of a package (as indicated by actual performance)
diminishes with time, handling, and previously incurred
damage. A prOperty not reflecting these losses in strength
is not capable of reflecting real conditions. Maltenfort
also argues that most products will arrive in gOOd condition
packed in boxes which would not be in compliance with a
compression standard, but failed to point out the compression
standard used, or how far out Of compliance the boxes were.
This argument can be discarded merely by examining the
nature Of material requirements. Material requirements are

limited to protecting some nonexistant "average" product

55

against reasonably expected hazards. Since the standards are
set up tO assume that a large majority Of boxes will arrive
with the contents in good condition, it can be assumed that
most cases only slightly out Of compliance will also arrive
with contents intact. If the boxes Maltenfort refers to were
out Of compliance by a high degree it is likely that the
standards were not set at a reasonable level.

Freight packaging requirements based on compression are
not without serious short comings though. These shortcomings
arise, primarily, because, as outlined above, these compres-
sion requirements would be a material property requirement
and will present the same problems involved with material
property requirements discussed earlier. In brief these are:

l) The requirements must be aimed at broad groups of
products, or an "average" product, and cannot take into
account the individual product differences contributing so
significantly to package performance.

2) Material property tests and related requirements
are normally meaningful for only one type Of material, hence
prohibiting alternative materials. Both burst and compression
testing are aimed at fibreboard. Requirements, based on
these test, discriminate against other, more recently
develOped packaging materials.

3) Because they fail tO account for individual product
differences, and because they discriminate against alternative

packaging materials, material property requirements can

56

frequently prevent a firm from minimizing the cost Of their
packaging-distribution system. This is, by far, the weakest
point Of any material property requirement.

Finally, even though there are serious drawbacks tO
requirements based on compression, compression is better
suited for Freight Rule requirements than is bursting strength.
The advantages being achieved primarily through better corre-
lation with actual performance. If some sort Of material
requirements are to be retained, either on an interim basis,
or as an alternative to performance testing, it is urged that
these requirements, in some way, be based on compression

strength.

VII Recommendations
A. It is recommended that every effort be made tO urge

the Uniform Classification Committee tO adopt performance

 

£3535 for freight rule requirements, instead Of burst tests
or other material tests. The major reasons for urging this
switch are:

1. Performance standards will allow packages to be
designed to meet the needs Of the individual product.

2. Performance standards will not force products
to be packaged in fibreboard.

3. Primarily because Of the above reasons, perfor-
mance standards can allow firms to achieve the least total
costs for packaging and transportation.

B. Since forces Opposed to performance standards may
delay their adoption, it is recommended that a compression
standard be adopted, as an interim requirement for corrugated
board. The major advantage compression Offers over burst is
a higher correlation with actual performance.

1. Since direct comparison between cases in in-
adequate for the needs Of a freight rule, it is recommended
that a unit Of comparison be adopted tO separate board into
qualities. These methods Offer good possibility here:

a) The edge crush test
b) Compression strength for a standard box size
c) Compression per unit Of perimeter as computed

by exponential method devised by McKee and
Buchanan

57

58

C. If it is found advantageous to retain a material
requirement for some applications after the adoption Of
performance standards it is recommended that interim compres-

sion standards be retained.

10.

ll.

12.

BIBLIOGRAPHY

Whittsitt, W.S., "Theory, Use and Calibration Of Bursting
Strength Testers, Part 1", Boxbd Cont., Vol. 80 #1,
Aug. 72, p34-36.

Whittsitt, W.S., "Theory, Use, and Calibration Of Bursting
Strength Testers, Part 2", Boxbd Cont., VOl. 80 #2, Sept
72, p53-57.

Bettendorf, H., "Paperboard and Paperboard Containers-
A History", Board Products Publishing CO., Chicago, Ill,
1946.

Maltenfort, G., Morse, S.A., Babakitis, J., "Standardi-
zation and Calibration Of the Mullen Burst Test by
Electronic Instrumentation", Tappi, Vol. 54, #7,

July 71, p1123-7.

ASTM Annual Book Of Standards, Vol. 15, 1973.

Randall, E.B., Lashof, T.W., "Burst Strength Variability",
Tappi, Vol. 53, #5, May 70, p779-809.

Maltenfort, G., "Freight Rule Regulations and Packaging
Specification, Parts 1,2,3, Papbd Pkg., Vol. 49 #4,5,6,
1964.

Kivlin, A.P., "Box Quality Identification- Significant
Changes Proposed for Boxmaker's Certificate", Fibre Cont.,

McKee, R., "Top Load Compression", Tappi, Vol. 40 #1,
Jan. 57' p57-64o

Buchanan, "Correlating Lab Tests and Field Performance",
Pkg. Tech., Vol. 15 #109, Nov. 69.

Anon., "Short Column Test Standards", Tappi, VOl. 53, #7,
July 70, pl379-80.

Buchanan, "Combined Board Characteristics that Determine
Box Performance", Papbd Pkg., Vol. 49 #9, Sept. 64,
p74-85.

59

13.

14.

15.

l6.

17.

18.

19.

20.

21.

22.

23.

24.

25.

26.

27.

28.

60

Maltenfort, G., "Compression Strength Of Corrugated
Containers", Fibre. Cont., Vol. 41, #789, 1956.

McKee, R., Gander, J., Wachuta, J., "Compression Strength
Formula for Corrugated Boxes", Papbd. Pkg., Vol. 48 #8
Aug. 63, pl49-59.

Mirasol, 3., "Evaluation Of Some Existing Empiracal
Equations for Top-to-Bottom Compression Strength Of
Corrugated Fibreboard Boxes", Thesis, Mich. St. Univ.,
1966.

McKee, R., "Flexural Stiffness", Papbd. Pkg., Vol. 47
#12, Dec. 62, Plll-l8.

Maltenfort, G., "Structural Aspects Of Corrugated Board",
Tappi, VOl. 53, #7, July 70, p1223.

Jonson, G., TorOi, M., "Edge Crush Test for Corrugated
Board", Papbd. Pkg., Vol. 54 #7, July 69, p35.

McKee, R., "Puncture and Box Performance", Papbd, Pkg.,
Vol. 49, #9, Sept. 69, p85.

Maltenfort, G., "Mullen vs. Puncture for Corrugated",
Papbd. Pkg., Vol. 44 #9, Sept. 59, p60-6.

Maltenfort, G., "Burst as a Freight Rule Test: Not a
Specification", Pkg. Eng., Vol. 13, #6, Mar. 68, p64.

Wolf, M., "How Box Length, Width Affect its Compression
Strength", Pkg, Eng., VOl. 16, #10 Oct. 71, p68-70.

Baladis, V., Hawkins, 3., "Assessment Of Damage to
Corrugated Containers", Appita, Vol. 25, #5, Mar. 72,
p 362-39.

Zusi, C., "Readings in History Of Container Design and
Testing, Parts 1&2", Boxbd, Cont., VOl. 81 #12, July 74,
Vol. 82, #4, Nov. 74.

Jonson, G., "Transport Trials with Corrugated Board
Boxes to Europe and U.S.A.", Research Report, Swedish
Packaging Research Institute. 1974.

McKee, R., "Edgewise Compression Strength Of Corrugated",
Papbd, Pkg., VOl. 46, #11, Nov. 61, p70.

Fibre Box Handbook, Fibre Box Association, Chicago, Ill,
1971.

 

Bettendorf, "Pridham Decision- Without it What?", Papbd.
Pkg., Mar 64 VOl. 49, #3, p35.

29.

300

31.

32.

33.

61

Easter, R., Holmes, M., Unpublished Research Paper,
Pillsbury & CO., 1974.

Henzi, A.N., "Survey Of Test Methods Currently Used for
Simulating the Transportation Environment, Phase II."
General American Transportation Corp, Niles, Ill, 1971.

Kellicutt, K.Q., Landt, E.F., "Basic Design Data for the
Use Of Fibreboard in Shipping Containers.", U.S. Dept.
Of Ag., Forest Service, Forest Products Laboratory
Bulletin, D1911, p. 39, 1951.

Paine, F.A., Fundamentals Of Packaging, London, Black &
Sons, Ltd., 1962.

 

Olsson, David L., "The Possible Impact Of Now Packaging
System Concepts on Traditional Corrugated Box Methods,"
Thesis, Michigan State University, 1967.

 

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