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THESIS

 

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This is to certify that the

thesis entitled

Downforce to Remove and Consumer Perceptions of
Type 1A.Continuous Thread Child-Resistant Closures

presented by
Beth Emma Waggoner

has been accepted towards fulfillment
of the requirements for

M- S . degree in Packaging

ajor professor

Hugh E. Lockhart, Ph.D.

 

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DOWNFORCE TO REMOVE AND CONSUMER PERCEPTIONS
OF TYPE 1A CONTINUOUS THREAD CHILD-RESISTANT CLOSURES

BY

Beth Emma Waggoner

A THESIS

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

MASTER OF SCIENCE

School of Packaging

1989

2.22
J .3

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a?

5974'

ABSTRACT

DOWNFORCE TO REMOVE AND CONSUMER PERCEPTIONS
OF TYPE 1A CONTINUOUS THREAD CHILD-RESISTANT CLOSURES

BY

Beth Emma Waggoner

Four similar child-resistant closures were evaluated to
determine the level of downforce necessary for a successful
removal” .Aihinimum required.downforce value was established
by testing with an automated torque machine. Using an
instrumented bottle the force actually exerted during'a
removal was measured. Subjects were asked perceptual

questions regarding the openings.

Analysis of the minimum downforce data indicated differences
between the four closures, with one at a lower required
downforce than the others. The downforce measurements for
subjects also showed that same closure as different by

requiring a lower force.

Comments from the subjects indicated that the majority did
not understand how to operate the child-resistant closures
(x1 the market, and several expressed negative feelings.

Comparatively there were few instances during the testing

where the subjects couldn’t remove the closures, and only
seven times where the subjects did not generate the

necessary minimum downforce.

Copyright by
Beth Emma Waggoner

1989

DEDICATION

This thesis is dedicated to my mother Katherine Waggoner,
for without her support it would never have been finished,
and to the memory of two men who also made a difference;

my father Wayne Waggoner, and my friend Joe Irvin.

ii

ACKNOWLEDGEMENTS

I would like to thank my committee members for their
time and input; Dr. Hugh Lockhart, Dr. Susan Selke, Dr.
Bruce Harte, and Dr. Robert Wilkinson. My sincere thanks
are extended to Dr. Gary Burgess for his assistance in
designing and machining the instrumented bottle. I would
also like to thank Dr. John Gill for his help in the
statistical design and analysis of this research.

I would also like to express my gratitude to Dr.
Julian Lee who spent many hours helping me understand what
a statistical design and analysis was, and as a friend was
never too busy when I had trouble.

Finally, the people whose friendship and caring made
all the difference: Jan Toebe, Vandana Kohli, Lisa
Hewartson, Mark Schroeder, Jim Konczal, Suresh Nagaraj,

and a special thanks to Paul Singh.

iii

TABLE OF CONTENTS

page
LIST OF TABLES ........................................ vi
LIST OF FIGURES ....................................... ix
INTRODUCTION ........................................... 1
LITERATURE REVIEW
History .......................................... 3
Testing Protocol ................................. 7
Legislation Effects .............................. 9
Human Strength Studies .......................... 12
Machine Minimum Downforce Measurements .......... 14
MATERIALS AND EXPERIMENTAL METHODS
Materials
Closures/Bottles ............................ l7
Instrumented Bottle ......................... 20
Auto-Torque Tester .......................... 22
Additional Equipment ........................ 25
Experimental Methods
Auto-Torque Tester .......................... 26
Preliminary Work - Human Subject Testing....28
Testing Procedure ........................... 31
ANALYSIS OF DATA
Machine Minimum Downforce Measurements .......... 35
Human Subject Testing ........................... 38
Acceptance Question ......................... 4O
Scaling Question ............................ 45
Subject Downforce Measurements .............. 50
Preference Question ......................... 54
General Trends .............................. 60
Comments of Test Participants ............... 67

iv

page
CONCLUSIONS ........................................... 69
RECOMMENDATIONS ....................................... 71
BIBLIOGRAPHY .......................................... 73
APPENDIX A
Table 1. Subject’s bottle and closure grips
used when removing closure #1. ...... 76
Table 2. Subject’s bottle and closure grips
used when removing closure #2 ....... 78
Table 3. Subject's bottle and closure grips
used when removing closure #3 ........ 80
Table 4. Subject’s bottle and closure grips
used when removing closure #4 ........ 82
APPENDIX B
Human Subject Questionnaire ..................... 84
APPENDIX C
Table 8. Subjects listed by age group
and sex .............................. 89
APPENDIX D
Table 9. Raw data from the Acceptance
Question ............................. 91
Table 10. Raw data from the Scaling
Question (1/10") ..................... 93
Table 11. Raw data from the Preference
Question ............................. 95

Table 12. Raw data from the Subject
Downforce Measurements (lbs) ......... 97

Table

Table

Table

Table

Table

Table

Table

Table

Table

Table

Table

Table

Table

10.

11.

12.

13.

LIST OF TABLES

page
Subject’s bottle and closure grips used
when removing closure #1.... ............... 76
Subject’s bottle and closure grips used
when removing closure #2..... .............. 78
Subject’s bottle and closure grips used
when removing closure #3 ..... . ............. 80
Subject's bottle and closure grips used
when removing closure #4...... ............. 82
Data from the Machine Minimum Downforce
Measurements from the Auto-Torque
testing ....................... . ............ 36
One-Way Analysis of Variance for
the Machine Minimum Downforce
Measurements ............................... 37
Tukey's Test for the Machine Minimum
Downforce Measurements, looking for the
differences between individual closures....37’
Subjects listed by age group and sex ....... 89
Raw data from the Acceptance Question ...... 91
Raw data from the Scaling Question (1/10").93
Raw data from the Preference Question ...... 95
Raw data from the Subject Downforce
Measurements (lbs) ......................... 97

Data from the Acceptance question
of the human subject testing ............... 41

vi

Table

Table

Table.

Table

Table

Table

Table

Table

14.

15.

16.

17.

18.

19.

20.

21.

vii

Split-Plot Analysis of Variance
performed on the data from the
Acceptance question of the human

subject testing .........................

Tukey’s Test performed on the
Acceptance question data of the
human subject testing, looking for

differences between the age groups......

Tukey’s Test performed on the
Acceptance question data of the
human subject testing, looking for
differences between the individual

closures ................................

Data from the Scaling question
of the human subject testing, in units

of 1/10" ................................

Split-Plot Analysis of Variance
performed on the data from the
Scaling question of the human

subject testing .........................

Tukey’s Test performed on the
Scaling question data of the human
subject testing, looking for
differences between the individual

closures ................................

Data from the Subject Downforce

Measurements in units of pounds .........

Split-Plot Analysis of variance
performed on the data from the
Subject Downforce Measurements of

the human subject testing ...............

page

...43

...44

...44

...46

...48

...49

...51

...52

Table

Table

Table

Table

Table

22.

23.

24.

25.

26.

viii

page
Tukey's Test performed on the
Subject Downforce Measurement data,
looking for differences between the
age groups ................................. 53
Tukey’s Test performed on the
Subject Downforce Measurement data,
looking for differences between the
individual closures ........................ 53
Data from the Preference (ranking)
question of the human subject testing ...... 55
Friedman’s Two-Way Analysis of
Variance by Ranks performed on the
Preference question data to look for
an effect due to sex ...... . ................ 57
Friedman’s Two-Way Analysis of
variance by Ranks performed on the
Preference question data to look at
a possible age group effect ................ 59

Figure

Figure

Figure

Figure

Figure

LIST OF FIGURES

page
Sketch of the instrumented bottle
used in the human subject testing
(not drawn to scale) ...................... 21
Inner construction of closure 2
(not drawn to scale) ...................... 61
Inner construction of closure 1
(not drawn to scale) ...................... 63
Inner construction of closure 3
(not drawn to scale) ...................... 64
Inner construction of closure 4
(not drawn to scale) ...................... 65

ix

INTRODUCTION

This study was initiated to examine downforce requirements
necessary to remove specific child-resistant closures using
a machine measurement and human strength measurements. The
closures tested. fall under the classification. of .ASTM
Continuous Thread Type IA (ASTM, 1988), and are a style
commonly referred to as "push and turn" closures. To remove
one of these closures, a subject must exert a downforce and
a torque at the same time, two dissimilar motions. If
sufficient downforce is not applied, the closure will not
be removed. For this study an assumption was made that the
downforce, not the torque, is the inhibiting force to open

these closures.

There are two main objectives of this study. The first is
to establish the minimum downforce required to remove the
closures by utilizing an automated torque testing machine.
Secondly, to measure the downforce actually exerted by
subjects when attempting to remove a closure. The subjects

were also asked to answer questions regarding the removal

2
attempt. The data was statistically analyzed looking for
any effects due to the age group of the subject, the sex
of the subject, the particular closure being manipulated,

and any interactions among these variables.

It is hoped that information resulting from this study may
be used to help evaluate downforce requirements for new and

existing push and turn child-resistant closures.

L I TERATURE REVI EW

History

Safety in the home has been and continues to remain a major
issue among consumers today. Of the many accidents that
occur in the home, one category involves accidental
ingestions of poisonous products by young children. In 1969
the American Association of Poison Control Centers reported
over 76,000 cases of accidental poisonings involving
children under five years of age (Verhulst, 1970). Of
these, almost 90% were associated with children three years
of age and younger. These numbers include only cases
reported to a poison control center. The actual figure has
been estimated at seven to eight times higher. Statistics
such as these helped push legislation that required child-
resistant (CR) packaging on many potentially dangerous

medicines and household products.

Child-resistant packages have existed for over 100 years
(Sacharow, 1988). But it took until the early 1960’s for

the United States Government.to become actively involved.and

seriously investigate the situation. Initially the
attention was focused on changing the environment
surrounding the child by modifying the actions of adults
(Maisel, 1975). Informational programs and other forms of
publicity were employed to try to educate adults on the
dangers of accidental poisonings, and they urged the public
to lock up potentially dangerous substances or at least
place them out of reach of young children. These efforts
were not very effective in reducing the level of poisonings
(VanGieson, 1983). Young children are curious, and if
something is misplaced or left within their reach they will

often pick it up and put it in their mouth (Arena, 1970).

A new preventative viewpoint soon emerged. The focus
changed from modifying the child’s environment to modifying
the problem ingestants themselves (Maisel, 1975). This
could be accomplished in many ways including changing the
formulation of a product, or changing the products’
packaging. In late 1970, the Food and Drug Administration
(FDA) organized a committee of representatives from industry
and government to set guidelines for safer packaging

(VanGieson, 1983). Five main points emerged:

5

1- a closure should be difficult for a child to open,

2- adults should be able to easily remove and resecure
that same closure,

3- instructions on the operations of the package
should be provided,

4- the package should still be able to protect the
product contained within, and

5- a closure should only be called "child-resistant"

if it passes designated protocol tests.

At the same time the guidelines were published, Congress
passed the Poison Prevention Packaging Act of 1970, Public
Law 91-601 (ASTM, 1970). This Act together with the Poison
Prevention Packaging Regulations, provided a foundation to
begin to reduce accidental poison ingestions among young
children. Enforcement of the Act and Regulations was given
to the FDA, which relinquished control to the Consumer
Product Safety Commission (CPSC) in 1973. In the late
1970's the Environmental Protection Agency (EPA) was given
the responsibility of child-resistant packaging for

pesticides (VanGieson, 1983).

6

The law defined. a carefully chosen new term "special
packaging". Special packaging was "packaging that is
designed or constructed to be significantly difficult for
children under five years of age to open or obtain a toxic
or harmful amount of the substance contained therein within
a reasonable time and not difficult for normal adults to use
properly, but does not mean packaging which all such
children cannot open or obtain a toxic or harmful amount
within a reasonable time" (Code of Federal Regulations,
1987). In other words, most children should not be able to
open the package, ibut it was recognized that it is

impossible to keep all children out of all packages.

The Regulations list substances that are required to have
the special packaging, organized guidelines and
requirements, and set up a testing protocol. The guidelines
state that a product should not interfere with the normal
operation of the package, and the package should be reusable

if that was the intention of the design.

7

Testing Protocol

The testing protocol was defined as "the procedure for
testing' special. packaging' under' specific conditions to
determine if the packaging fulfills the standards...to be
considered a poison prevention package" (Perritt, 1975).
To be labeled as a child-resistant package at least 90% of
the adults tested must be able to properly operate the
package including opening and closing, and at least 85% of
the children must not be able to obtain access to the
package contents, even after' a demonstration (Code of

Federal Regulations, 1987).

Before undertaking a protocol test, the testing organization
must be given a complete description of the package to be
tested” .Any package designed.to contain pills may be filled
with placebos to imitate an actual package found in the
home. Any closures to be tested must first be manipulated
by the tester to make sure they are functioning correctly
(Press, 1970). Adults may test any number of packages, but
children are only allowed to manipulate two packages

(Perritt, 1975).

8

The protocol states that 200 children, half male and half
female, aged 42 to 51 months are to be tested in groups of
two. This allows for competition or teamwork, and gives
the children a greater sense of security by having another
child. present. The testing is conducted in settings

familiar to the children such as a school or daycare center.

When beginning the testing, both children are handed
identical packages and allowed five minutes to attempt an
opening (Press, 1970). It had been reported that many
children appear to lose interest if the package isn't opened
after three minutes, but this is not always the case
(Perritt, 1975). If the package is not opened the child
will be given a visual demonstration of the opening
procedure, and if they haven’t used their teeth yet, told
they may try that. The children are given another five
minutes to work, after which the packages are removed

(Press, 1970).

The protocol also states that 100 adults, 70% of which are
female, between the ages of 18 and 45 years must be tested
(Code of Federal Regulations, 1987). Each adult is tested

individually, and given five minutes to open and properly

9

close the package. They receive only the printed
instructions that appear on the package itself, no
demonstration is performed. When testing is completed the
packages are removed, and the data evaluated according to

the guidelines previously mentioned.

Legislation Effects

In 1972 the first legislation took effect and required the
use of child-resistant packages on specified products
(MacArthur, 1988). In that year, fatalities among children
under five years of age who accidentally ingested poisons
dropped from 216 to 149 (Maisel, 1975). By 1984 it was
reported that the use of child—resistant containers reduced
the number of accidental poisonings by 50% (Thein and
Rogmans, 1984). But a report from the American Association
of Poison Control Centers stated that in 1985 there were
still over 60,000 accidental prescription drug ingestions

(Jacobson et al., 1989).

Amrinvestigation.was initiated studying 2,015 incidents from
nine poison control centers in 1986 (Sharma, 1987). It was

reported.that 17% of the ingestions involved.a‘grandparent's

10

medication, and 14% occurred in the grandparent’ 3 home.
These findings are consistent with reports that many'people,
especially the elderly and also the handicapped, cannot
properly'operate the child-resistant.packages (Rider et al.,
1987). One study outlined in 1970 reported that of 281
women who mentioned having some degree of arthritis, 68% had
experienced difficulties in opening child-resistant closures
(Tainter, 1970). lOften people cannot read or understand the
opening and resecuring instructions printed on the packages .
Other problems can occur to compound this situation. The
packages themselves may be old and not functioning properly,
or the users may be transferring the medication to another

container.

A survey by the CPSC in 1976 reported that 70% of the
households contacted for a survey told of frustrations when
using child-resistant packaging (Sharma, 1987). Almost 20%
had replaced the child-resistant closures with a non-child-
resistant substitute. In 1987 Western Michigan University
reported that many times people will transfer medication to
a non-child-resistant container, disable the child-resistant
feature on a package, or simply leave the container open

(Western Michigan University, 1987). Many people are

ll

resentful of being forced to use child-resistant
containers if they have no small children at home (Dana,

1975).

A study conducted at Michigan State University in l987placed
articles in several women’s magazines and asked readers to
send in comments and suggestions relating to their
experiences with child-resistant packaging (Lockhart et al,
1988.). Almost 48% of the respondents listed problems with
push and turn closures. They were not able to properly
‘perform the two dissimilar motions, and could not easily
remove the closures. Specific products were mentioned, and
an investigation revealed many of the problems were
occurring with Type IA Continuous Thread Closures as
classified by the American Society for Testing and Materials
(ASTM, 1988). These closures have an inner and an outer
shell that snap together. When a downforce is exerted on
the outer cap it engages with the inner cap so that a torque
can be applied to the inner cap to remove the closure. If
insufficient downforce is maintained when applying the
torque, the outer shell will ride over the inner shell, and
the closure will not be removed” Some closure constructions

are such that a clicking sound will be heard, and when this

12
happens the consumer knows the removal attempt was not

successful.

Human Strength Studies

Many attempts have been made to measure human strength and
relate the findings to container openings. Two separate
studies on this subject have concluded that it is possible
to measure strength and relate it to containers, but it must
be done experimentally for each package type (Sharma, 1970,

Berns, 1981).

An early study conducted in 1971 by Dr. Wilton M. Krogman
for the Closure Committee of the Glass Manufacturer
Institute, measured what was called a "palm-push" force in
children ages 3 to 6 years (Krogman, 1970). This
measurement was defined as "the total force exerted when
the palm of the hand is pressed or opposed to an object,
and the object is pushed against". The measurements were
made when a subject pushed on a button mounted on the side
of a machine. A Jamar Hand Dynamometer mounted in the
machine detected the force, which was then read in pounds

pressure from an analog dial.

13
This same piece of equipment was utilized. by Western
Michigan University in 1987 (Sharma, 1987). Twenty-one
children aged 30 to 65 months, and twenty-eight adults aged
61 to over 85 years were tested. Readings were taken using
the subject's left and right palms. The data showed the
children aged 41 months and above had a similar-palm-push
strength as the adults aged 71 and above, in the range of
30 pounds +/- 5 pounds. The subjects were also asked to
open a push and turn closure. Both the adults and the

children had difficulties with the packages.

Another study conducted by the CPSC and presented in 1985
evaluated the ability of 700 adults to open child-resistant
packages, and additionally measured removal force values for
several child-resistant packages (Rider et al., 1987). The
subject’s ages ranged from 18 to 75 years. Three types of
child-resistant closures were tested, a snap cap, lug-style
closure, and.push and turn closure, the style which was also
used in this researdh. This closure was applied at two
application torques, 10 in-lbs and 20 in-lbs, hereafter

referred to as AT=10, and AT=20.

14

The subjects were asked to open a container, and the times
to open and success rates were recorded. Overall, the push
and turn closure (AT=20) was rated last. Eighty-nine
percent of adults aged 18 to 45 years could open and
properly reclose the container, but this dropped to less
than 50% of the adults aged 71 to 75 years. These same
closures were removed using a piece of equipment specially
designed by the CPSC. This equipment simultaneously
measures the downforce to open, and the removal torque.
This testing was conducted by CPSC operators. Again the
push and turn (AT=20) ranked last, requiring between 17.2

and 22.5 pounds for removal.

Although the previous work yielded important information
about human strength and the ability of adults to open
child-resistant packages, no study has been found that
directly measures the downforce a subject exerts when

removing a CR closure.

Machine Minimum Downforce Measurements

ASTM D3471-82 describes a test method to determine the "top-

load-to-engage", or minimum downforce value to engage the

15

removal lugs on a Type 1A.child—resistant closure (ASTM,
1988). To conduct the test, representative closures are
applied to bottles which are placed in a torque measuring
device. Weight is applied to the closure until a specific
removal torque value can be reached by rotating the closure.
This test method requires an operator to manipulate the
closure during the test by rotating the closure, and by
manually placing weights on a weight collar. For this
research, the concept of "top-load-to engage" was used to

devise a modification of the ASTM Standard Method.

An automated torque testing machine was used to determine
the minimum downforce to remove the test closures. The
machine was calibrated with dead weights according to the
manufacturers instructions before undertaking any testing.
An operator runs the machine through an interfacing computer
keyboard, therefore eliminating any operator variability.
The force values were input in the system in one pound
increments starting at a value below the suspected minimum
downforce as determined by preliminary testingu .A value was
considered to be the minimum downforce if the force caused
the two pieces of the closure to engage, and the machine to

remove the closure. The resulting removal torque was shown

16

by the machine, but a torque value did not determine a
minimum downforce value as dictated in the ASTM standard.
For a description of the operation see the Materials and

Methods section.

MATERIALS AND EXPERIMENTAL METHODS
Materials

Closures/Bottles

Four different 38 mm child-resistant closures were
utilized in this study. They are considered type IA
according to ASTM D3475-83 (ASTM, 1988). All four were
molded from polypropylene in a two-piece push-and-turn
style, but each.had a different inner structure, and they
were supplied by four different manufacturers. The caps

tested were:

Van Blarcom Saf—Cap l
Sunbeam FG "H" Series
Kerr CR1

Owens-Illinois Clic-Loc II.

The liners used in the closures were of a similar

pulp/aluminum foil/saran coated material.

The Van Blarcom Saf-Cap 1 samples were obtained from Van

Blarcom Closures, Inc. in Brooklyn, NY. The Saf-Cap 1 had
17

18

a liner retaining ring built into the inner shell to hold

the liner in place.

The Sunbeam FG "H" Series closures were obtained from
Sunbeam Plastics Corporation in Evansville, IN. This

liner was glued into place.

The Kerr CR1 closures were obtained from the Kerr Glass
Manufacturing Corporation in Lancaster, PA. The liner had
a lubricating finish of microcrystalline wax,and was glued

into place.

Lastly, the Owens-Illinois Clic-Loc II was obtained from
Owens-Illinois, Inc. in Toledo, OH. A lubricating film of
microcrystalline wax was applied to the liner which was

glued into place.

Hereafter the closures will be referred to as number one
through number four, but the identity of each will not be
specified. This was done due to the funding requirements
of the research, and the cooperative nature of the

suppliers involved.

19

All four closures operate in similar fashion during
application and removal. They are composed of a separate
inner cap and outer shell which snap together. They all
have a positive-on feature which, through a series of
lugs, springs, or another systems, automatically connects
the two shells to allow for easy securing when a clockwize
torque is applied. To perform a removal, it is necessary
to apply a downforce and counterclockwize torque. This
motion is referred to as simultaneous dissimilar motion.
The downforce acts to engage the inner and outer pieces of
the closure, allowing the two pieces to move as one when a
torque is applied, which allows closure removal. If the
downforce is not sufficient, or not kept at the correct
level, the two pieces will separate, and the outer shell
will slide over the inner cap resulting in a non—removal

situation.

The bottles used in this study were obtained from the
UpJohn Company in Kalamazoo, MI. They were molded from
high-density polyethylene containing titanium dioxide and
zinc stearate. They had a nominal capacity of 130 m1, a

finish size of 38mm, and were square in shape.

20
Instrumented Bottle

An instrumented bottle was designed to use with human
subject testing. A block of wood was worked into the
shape of a bottle, and cut into two pieces. An Omega DS-
350 force transducer was mounted between the blocks, and
four stabilizer bars placed at the corners to prevent
relative rotation of the two wooden pieces (Figure 1). A
test bottle was cut apart, and the lower section placed
over the bottom block. To operate the instrumented
bottle, a closure was applied to a test bottle, and the
bottle cut to a specified height. The top section of the
bottle containing the closure was then placed over the top
wooden block. The bottle was handed to a subject who was
asked to remove the closure by mimicing an actual opening
situation. When a subject applied a downforce to the top
section of the instrumented bottle, the force transducer
would detect the force and relay it through an Omega DP-
350 digital pressure indicator to a Linseis L6012 strip
chart recorder. The pressure indicator and strip chart
recorder were calibrated using dead ‘weights to record

force, in tenths of a pound, used by the subject when

Closure to be
tested (fits
over a wooden
block) 1_%

 

Stabilizer

21

 

 

 

 

 

 

0".e

---
.----.
)

 

 

bars-uel

Force

‘
7

 

 

 

 

transducer_“‘§‘~‘~“Ei///)W
i

Bottom of
bottle (fits
over a wooden
block) -—-—-?

 

i0o
6)
O0

’.------------

'- ——---—-—-- O
~———-.—~.—-—---

.1

 

 

 

Figure 1. Sketch of the inettulented bottle used in the hunen
subject testing (not drawn to ecele).

22
opening the closure. This gave a hard copy of data to be
used for evaluation purposes. The recorder chart was

operated at a speed of 12 inches per minute.

Auto-Torque Tester

An automated torque testing machine was received on loan
from Automated Dynamics Corporation. This machine
interfaced with an IBM XT computer and an Epson LX—800
Series printer. The Auto-Torque was capable of applying
and removing push-and-turn child-resistant closures. It
generated tables and graphs from these tests. An operator
would input dimensional information into a file which was

later recalled to perform a test.

Before conducting any testing, the Auto-Torque was
calibrated to read to one/one-hundreth of a pound

according to the manufacturers instructions.

To conduct an application of a closure, the operator
places the closure on the bottle and turns it until the
first resistance is felt. This positions the closure

properly so the machine can apply a torque. The bottle is

23

then set on a plate inside the Auto-Torque. The operator
recalls the dimensional information from the computer
memory for the specific bottle and closure. In the
application mode, the computer asks for an application
torque and downforce. After both of those variables are
entered, a set of four jaws on the plate closes upon the
bottle to hold it securely in place. Next an upper plate
descends, stopping just short of the top of the closure.
An upper set of three jaws on this plate closes upon the
closure and the machine applies the specified downforce.
The 'upper' plate and. the jaws rotate, and. applies the
specified torque. When the proper torque value is
reached, the upper jaws stop rotating, and open to release
the closure. The upper plate rises, and the lower jaws
open to release the bottle. The operator removes the
bottle and by a slight manipulation of the closure, can
tell that the application was successful. The computer
then plots a graph showing the torque and downforce
changes during the application as a function of time. It
also prints the highest torque value reached during the

application.

24
To conduct a removal, the bottle is once again placed on
the plate, and the dimensional information again recalled.
The Operator chooses the removal test command, and is
asked to specify a removal downforce value. The lower
jaws close around the bottle, and upper jaws move into
position” The .Auto-Torque applies the downforce, and
begins the removal rotation. If the downforce is
sufficient. to .allowr the 'two shells of ‘the closure to
engage, the torque from the machine allows removal of the
closure. If the downforce is not large enough to keep the
two parts engaged, the torque will not remove the closure,
and the outer cap would slide over the inner cap. If this
occurs, the operator can repeat the test, but increase the
downforce value in increments of one pound. This
procedure is repeated until the closure is removed. The
downforce applied at the time the closure was removed is

called the minimum downforce to remove.

In all of’ the applications performed, the application
torque used was 19 in-lbs (United States Pharmacopeia,
1985). No information was available on actual application
downforces used in industry, and 10 pounds was chosen as a

standard.

25

Additional Equipment

An Owens-Illinois Spring Torque Tester was used during the
human subject testing to resecure some of the closures.
It was not convenient to resecure the numbered closures
between test subjects using the Auto-Torque, so they were
reapplied to 19 in-lbs on the Owens-Illinois Torque
Tester. The torque tester used has been calibrated
according to the .ASTM standard. method. D3474-80 (ASTM,

1988).

Additionally, the Auto-Torque malfunctioned during the
time the human subject testing was being conducted, so a
portion of the closures to be used with the instrumented
bottle were applied with this tester. This was feasible
for this testing, as a study presented in 1988 showed no
statistically' significant. differences Ibetween ‘using ‘the
Auto-Torque and an Owens—Illinois Spring Torque Meter

(Automated Dynamics Corporation, 1988).

26
Experimental Methods

Auto-Torque Tester

It was recognized that it would be impractical to try to
apply closures immediately before removal by human
subjects because of the time required for application and
because of scheduling requirements for machine use and
subject interview times. Therefore, a time interval was
determined over which the removal torques for the closure
systems would not change from day to day. So, before
beginning' any testing, an optimal time period. between
application and removal was determined. A short torque
degradation study was conducted over a six day period.
Removal torque was measured at time zero (immediate
removal) and after 4, 5, and 6 days. An assumption was
made that if the torque was not changing rapidly over a
time period neither would the associated downforce value.
After analyzing the torque data, a time period of five
days was chosen. After five days the removal torque had
changed relative to time zero, but not when comparing to

four or six days.

27
All closures, whether to be removed by machine or by
subjects, were set up to be applied on the Auto-Torque.
This would remove any possible operator variability. Part
way through the subject testing the machine malfunctioned,
so the last few closures were applied using the Owens-
Illinois Spring Torque Tester. To keep operator
variability at a minimum, only one operator performed the

applications.

Sixteen of each of the four closures were tested. The
applications were performed over a four day period. After
storage for five days the closures were removed using an
estimation of the minimum downforce required to open each
closure. It was decided to begin testing at two pounds
below the lowest recorded downforce value for each closure
determined from previous testing. This was done to insure
that no closure would be removed on the first removal

attempt. The exception was closure 2. Previous testing
showed the removal force to be close to 2 pounds. The
machine operates in increments of 1 pound, and so the
testing was started using a downforce of 1 pound. The

resulting minimum downforces for each closure were:

28

Closure 1 6 pounds
Closure 2 1 pound
Closure 3 6 pounds
Closure 4 4 pounds

The differences in the forces are due to the different
inner structures of the closures. The downforce required
depended on whether the closure had a spring system that
had to be compressed, lugs to be pushed into a slot, or

another method of mating the two pieces.

Preliminary Work - Human Subject Testing

This study was designed to look at four different adult
age groups: 25-45, 46-55, 56-65, and 66-85 years. It was
felt that starting at age 25 many subjects would have
small children in their home, or friends visiting with
young children. At ages up through 85, the subjects may
have grandchildren visiting. Within each group, four men
and four women were tested. To qualify as a valid test
subject, the person had to be living in a non-
institutionalized setting, and have the ability to self-

administer medication. Volunteers were located through

29

local advertising, and a local Kiwanis Club.

Before testing, the way in which people grip bottles and
closures was studied. This was done by handing a random
group of people a bottle/closure system, and observing how
the bottle and closure was held. Several variations were
found. and 'these ‘were coded. and later listed. on (every
subject's questionnaire (Appendix A, Tables 1-4). Two
main closure grips were found, one using the fingers and
thumb in some variation of a pincher grip, and another
where the palm of the hand is applied to the top and
around the circumference of the top panel. Six main
bottle grips were used. A subject could place the bottle
on the table surface and lean to open, or place the bottle
against their leg and push. The bottom of the bottle
could rest on a subject’s palm. The subject could place
all four fingers around the bottle, or place the little

finger, or ring and little finger underneath for support.

A questionnaire was developed for the purpose of obtaining
information about subject’s perceptions of useability of
closures (Appendix B). The first page was used for basic

demographic information, and to determine if a subject was

30

familiar with the closures being tested. To help clarify
this, samples of all four closures were applied to
bottles, which were placed in front of the subject for
viewimg. On the second page subject’s were asked about
the ease of opening of all four closures, which has been
coded as the Scaling question (Meilgaard, 1987). A line
for each closure ran horizontally on the page. The left
end point was labelled "Very Easy to Open" and the right
end point was labelled "Very Hard to Open". The subject
would open a closure, and then placed a slash along the
line indicating his opinion of the opening. The distance
between the left end point and the slash mark was measured
to the nearest 0.1 inch, and this data was recorded for

later analysis.

On the third page subject’s were asked about how well they
liked each closure, which has been coded as the Acceptance
question. Each closure was removed separately, and the
response immediately marked on a separate scale. For this
test, a nine point scale was used which ran from
"Extremely Well Liked" to "Extremely Dislike". The
subject would place an "X" in a box next to the correct

response. Each box was later assigned a number from one

31

to nine, a one corresponding to "Extremely Well Liked" and

a nine corresponding to "Extremely Dislike".

The fourth. page asked. the subject to order the four
closures from one through four in comparison with each
other according to their overall Preference. The closures
were placed side by side, and the subject based his
decision on a direct comparison. They were allowed to
manipulate the closures if desired, but were not allowed

to look at their scoring on the previous two pages.

The final page was never given to the subject. On that
sheet the experimenter listed the hand positions the
subject used during the removal attempts, and the order in

which the closures were opened.

Testing Procedure

Upon arrival, the subject was ushered individually into a
designated room and given a place to sit at a table. The
rooms chosen were relatively small in size, and free from
distractions. The subject was handed the first page of

the questionnaire, and asked to take a moment to complete

32
the page. Every subject was assigned a number to insure
confidentiality. This number was placed on all the pages
used by the subject. A sample of each of the four
closures was placed on the table to show what types of

closures they would remove.

When finished, the subject was taken to another table
where the equipment was set up, and given a choice of
sitting or standing. They were instructed that they would
be asked to open four different closures and rate these on
three different scales. They would also be opening the
same four closures using an instrumented bottle to obtain

a force measurement.

A sample of each closure had been applied to bottles using
the Owens-Illinois Spring Torque Tester at an application
torque of 19 in-lbs. These four bottles were marked using
a numerical code to distinguish the closure styles.

All four bottles were placed in a brown kraft bag. Pages
two and three of the questionnaire; Scaling and Acceptance
questions; were placed side by side in front of the
subject. The subject was instructed to choose one bottle

from the bag, note the code number on both pages, and

33

remove the closure. They were reminded that they could
stand or sit, and that they were free to try to remove the
closure in any way they wanted. After a removal, whether
successful or not, the subject ranked the closure on both
scales. Next, the same closure style was placed on the
instrumented bottle and given to the subject. The strip
chart recorder was turned on, and the subject asked to
remove the closure. When finished, the subject was asked
to choose another bottle from the bag, and repeat the

procedure until all four had been tested.

Lastly, the four closures and bottles were again placed in
front of the subject along with the fourth page of the
questionnaire. 'The subject was asked to compare the
closures side by side, and rank them on the Preference
scale of one through four, one being the closure they
preferred the most overall, four being the closure they
least preferred overall. The subject was told to reclose
and reopen the containers as desired to help in the
rankings. They were not allowed to look at their previous

responses from the Acceptance and Scaling questions.

34
When the subject finished, they were shown the inner
structures of all four closures, and informed about how

the downforce operated to connect the two pieces and allow

for removal.

ANALYS I S OF DATA

The data was analyzed using several different techniques.

Machine Minimum Downforce Measurements

The machine minimum downforce measurements were set up in
a completely randomized design. The data from the testing

can be found in Table 5.

A One-Way Analysis of Variance was performed on the
machine downforce data (Table 6). The calculation
revealed a highly significant difference between the
downforce values for the four closures at a confidence
level of 99.9%. This analysis showed a difference, but
did not tell which closures were different from each
other. Tukey's Honestly Significant Difference Test
(Tukey’s Test) was performed on the data to reveal which
closures were different from each other (Table 7).
Tukey's showed that there was no significant difference

between closures 1 and 3, and closures l and 4.

35

36

 

 

Table 5. Data from the Machine Minimum Downforce
Measurements from the Auto-Torque testing.
Downforce (lbs)
Sample Closure #
Number
1 2 3 4
1 10 1 10 8
2 9 1 8 8
3 9 1 12 7
4 9 1 9 8
5 8 1 9 9
6 8 1 12 8
7 8 1 7 8
8 7 1 8 6
9 7 1 9 6
10 10 1 8 8
11 8 2 9 9
12 7 1 7 8
13 10 l 9 7
14 8 1 9 8
15 7 1 10 6
16 8 1 10 9
X 8.38 1.06 9.13 7.69

1.09 0.25 1.45 1.01

37

Table 6. One-way Analysis of Variance for the Machine
Minimum Downforce Measurements.

 

Source of Variation df F-Value
Total 63

Treatment (downforce) 3 200.95**
Error 60

 

**significant at alpha = 0.01

Table 7. Tukey's Test for the Machine Minimum Downforce
Measurements, looking for differences between
individual closures.

 

Closure # Mean (pounds) Ranked Order
3 9.13 A
1 8.38 AB
4 7.69 B
2 1.06 C

 

alpha 8 0.05

38

But there was a significant difference between closures 3
and 4, and between closure 2 and closures 1, 3, and 4.
Closure 2 had the lowest minimum downforce reported at a
mean value of 1.06 pounds, followed by closure 4 at 7.69
pounds, closure 1 at 8.38 pounds, and lastly closure 3 at

9.13 pounds.

Human Subject Testing

Fourty-one subjects were tested, but the data from only
the first eight (four male and four female) in each age
group was used in the analysis (Appendix C, Table 8). The
additional subjects were tested to assure there would be
32 sets of usable data. There were no problems
encountered during the testing, and the raw data from all
41 subjects, for all the questions, can be found in

Appendix D, Tables 9-12.

The human subject data was evaluated by using two
different techniques. The data from the Acceptance and
Scaling questions, and from the Subject Downforce
Measurements was analyzed by a Split-Plot Analysis of

Variance of a completely randomized design. This

39

experimental design is capable of handling factorial
treatments. For this research, there are two factors in
the main plot (age and sex), and one factor in the subplot
(closure type). Calculating’ a Split-Plot .Analysis of
Variance is similar to a One-Way Analysis of Variance, but
there are two resulting error terms, one from the main
plot and one from the subplot. Four age groups and the
two sexes were tested, creating eight possible factorial
combinations, or treatments. These eight treatments were
tested randomly, subjects of a certain age and sex were
not tested in any set order. For each subject, all four
closures were also tested randomly by having the subject

select one at a time from a bag.

The data from the Preference question was evaluated by
using Friedman’s Two-Way Analysis of Variance. Friedman's
test is used to examine sample data that has been ranked
on an ordinal scale (Siegel, 1956). It helps determine
whether the differences between the samples indicate that

they are from one population, or different populations.

There were instances where subjects were not able to

successfully remove the closures being tested. This data

40
was still used in all of the calculations. This was done
because the testing was set up to get consumer perceptions
and a measure of what forces will be exerted to try to
remove a closure. Obviously there are many instances at
home where a closure cannot be easily removed. It was
felt that the maximum force exerted, whether from a
successful removal or not, was a measure of what the
subject was capable of generating, and this was viable

information to including in the data analysis.

The age groups have been listed using a code number to
represent each group. Age group 1 is the subjects whose
ages fall in the range of 25 to 45 years old, age group 2
is the subjects whose ages run from 46 to 55 years, group
3 runs from 56 to 65 years, and lastly, group 4 runs from

66 to 85.

Acceptance Question

A Split-Plot experimental design was utilized to set up
and evaluate the data from the Acceptance question. The
data can be found in Table 13. This question is used to

ask the subjects about their like or dislike of the

41

Table 13. Data from the Acceptance question of the
human subject testing.*

Age Sex Closure #

l 2 3 4

 

35
35
35
35
35
35
35
35
50
50
50
50
50
50
50
50
60
60
60
6O
60
60
60
60
70
70
70
70
70
70
70
70

X»
*

HkDNCDxinIWKOWme\iNNdeNNU‘INbNmbwdm

8**
9**

wrune@135§3:3'H'HWIW:Z5:3:Z'flrq@1m:32§3:3'flhu"aletzaiz
h)dtfltthOSmtflCDUJme~dJ>Osmtva>cibtnLnKDNr050a>m<htthb
FJQ)NIdr4k)b~4LUKDm-bhuhlwobtoF*wtvhahJvah0k)qlvhaoxN.b
\ocntuuah»A<m~4nsuiq-utocncn~as>osqencu¢>m>mcncnhooxuiu:ern

 

*The choices run from one to nine. A "1" is
"Extemely well liked" to a "9" being "Extremely
dislike".

**Subject was not able to remove the closure from the
test bottle.

42
closure removal. A value of "1" means the closure removal
was "Extremely well liked", a "5" means the removal was
"Neither liked nor disliked", up to a "9" meaning the

removal was "Extremely dislike".

The results from the analysis of variance are shown in
Table 14. There was an effect due to the age groups
tested, and to the closure type. An effect due to the
interaction of sex and closure type was noted, but further
analysis of this was not possible. To determine any
differences between the individual age groups for the
Acceptance question (combining the closures into one group
as a whole), a Tukey’s Test was performed on the data
(Table 15). It was found that there was no statistically
significant difference 'between any of ‘the age groups.
This can be explained because Tukey's is a very stringent
test, and the mean values were just not far apart enough
to yield any statistically significant differences between
them. A lower value for the Acceptance question means
that the subject liked the closure better. The group 2
mean was 3.0, followed by group 1 at 3.88, group 3 at
4.47, and lastly group 4 at 4.81. The values of 3 to

roughly 5, puts the responses in the range of "Moderately

43

Table 14. Split-Plot Analysis of Variance performed on the
data from the Acceptance question of the human
subject testing.

 

Source of Variation df F-Value
Total 127
Main Plot 17
Age 3 3.26**
Sex 1 0.31
Age x Sex 3 1.35
Error 1 24
Sub Plot 31
Closures 3 6.73***
Age x Closures 9 1.08
Sex x Closures 3 2.60*
Age x Sex x Closures 9 1.30

Error 2 72

 

*significant at alpha = 0.10
**significant at alpha = 0.05
***significant at alpha = 0.01

44

 

 

 

 

Table 15. Tukey’s Test performed on the Acceptance question
data of the human subject testing, looking for
differences between the age groups.

Age Group Mean (units) Ranked Order

4 4.81 A
3 4.47 A
1 3.88 A
2 3.00 A
alpha = 0.05
Table 16. Tukey's Test performed on the Acceptance
question data of the human subject testing,
looking for differences between the individual
closures.

Closure # (units) Ranked Order

3 4.91 A

4 4.66 A

1 3.31 B

2 3.28 B
alpha = 0.05

45

liked" to "Neither liked nor disliked".

An effect due to the closure tested was noted from the
Acceptance analysis. Tukey's Test was used to look for
the (differences .between 'the individual closures (Table
16). It was found that the means for closures l and 2
were significantly different from the means of closures 3
and 4. This indicates that closures 1 and 2 were liked
better than closures 3 and 4. The means for closure 1 and
2 were very close, at 3.31 and 3.28 respectively; followed

by closure 4 at 4.66 and closure 3 at 4.91.

Scaling Question

The Scaling question was used to obtain information about
whether a subject thought the closure removals were easy
or difficult. A subject places a slash along a six inch
line corresponding to the ease of opening. The left end
point was labeled "Very easy to open" and the right end
point labeled "Very hard to open". The distance from the
slash mark to the left end point was measured and

recorded. The data can be found in Table 17.

#

Closure

in units of 1/10".*

46

Sex

Age

 

Data from the Scaling question of the human

subject testing,

Table 17.

k *
.x *
99942718882450468121690399540357

0.1nuso3nusuoqlnvl.3n4:.5.UneR51.113131.Ua4132.ucanv5.5
* *

.x *
3107671591219494971981083433138

5.7**

1323402011033401431005130451504.

8531504458338645887835471223733
00020500100201002200140032100010

.1

*
89799011541439.3034.1879789544315
00.11326101113241913.3142304119311041...

MMMMFFFFMMMMFFFFMMMMFFFFMMMMFFFF

35
35
35
35
35
35
35
35
50
50
50
50
50
50
50
50
60
60
60
60
60
60
60
60
70
70
70
70
7O
7O
70
70

A 0.1" is "Very

easy to open" to a 6.0" which is "Very hard to

open".
**Subject was not able to remove the closure from the

to 6.0".

 

*The scale runs from 0.1"

test bottle.

47

The Split-Plot Analysis of Variance performed on the
Scaling question data showed an effect due to the closure
type tested and a slight effect due to the interaction of
sex and closure type (Table 18). Tukey’s Test was
utilized to determine which of the closures were different
from each other (Table 19). There was no significant
difference noted between closures 1, 3, and 4, but closure
2 was different than the other three. The mean value for
closure 2 was lower than the others at a level of 1.30",
followed by closure 1 at 2.16", closure 3 at 2.64 ", and
lastly closure 4 at 2.79". A lower scaling value shows
that the subject felt the closure was easier to open.
This evaluation indicates that the subjects felt closure 2
was easier to remove than the other closures. The exact
reasons again are not evident, but it may be partially due
to the inner construction of closure 2 as compared to the
other closures. An explanation of the inner constructions

is provided later in this section.

Again, as in the Acceptance question, an interaction was
noted between the sex of the subject and the closure type
tested, but it was not possible to analyze the interaction

to determine which sex /closure effect differed.

48

Table 18. Split-Plot Analysis of Variance performed on the
data from the Scaling question of the human
subject testing.

 

Source of Variation df F-Value
Total 127
Main Plot 17
Age 3 1.21
Sex 1 0.00
Age x Sex 3 0.52
Error 1 24
Sub Plot 31
Closures 3 10.21***
Age x Closures 9 0.97
Sex x Closures 3 2.48*
Age x Sex x Closures 9 1.25

Error 2 72

 

*significant at alpha = 0.10
**significant at alpha = 0.05
***significant at alpha - 0.01

49

Table 19. Tukey’s Test performed on the Scaling question
data of the human subject testing, looking for
differences between the individual closures.

 

Closure # Mean (1/10") Ranked Order
4 2.79 A
3 2.64 A
1 2.16 A
2 1.30 B

 

alpha = 0.05

50

Subject Downforce Measurements

The Subject Downforce Measurements were taken to gather
information about what level of forces are exerted to try
to remove a closure. The data can be found in Table 20.
The Split-Plot Analysis of Variance showed a slight effect
due to the subject age group, and an effect on downforce

due the type of closure involved (Table 21).

Tukey’s Test. on the effect. of' age group) on downforce
showed no significant differences between any of the age
groups (Table 22). The mean downforce for age group 2
(46-55 years) was the lowest at 14.21 pounds, followed by
group 1 (25-45 years) at 17.26 pounds, group 4 (66-85
years) at 17.88 pounds, and lastly group 3 (56-65 years)

at 22.47 pounds).

Tukey’s was utilized to determine which closure was
different (Table 23). Tukey’s Test showed that closures
1, 3, and 4 were not significantly different from each
other, but closure 2 was different from all of them.
Closure 2 had a lower mean downforce value at 14.26

pounds, and it can be said that the subjects used less

51

Table 20. Data from the Subject Downforce Measurements
in units of pounds.

 

Age Sex Closure #
l 2 3 4
35 M 16.9 11.2 21.3 13.4
35 M 21.2 13.3 15.5 17.8
35 M 19.6 6.0 22.6 15.0
35 M 22.0 13.0 11.0 14.4
35 F 30.0 23.4 42.1 27.0
35 F 20.3 17.5 23.2 13.4
35 F 16.6 12.5 15.6 16.1
35 F 15.5 9.6 17.2 18.2
50 M 21.8 12.7 10.1 23.7
50 M 17.3 12.3 8.6 19.1
50 M 12.4 5.5 13.3 6.6
50 M 7.6 8.5 14.9 13.5
50 F 9.5 9.4 19.6 16.1
50 F 26.4 18.1 21.1 21.9
50 F 13.3 9.4 13.4 16.5
50 F 18.4 4.2 16.6 12.9
60 M 14.3 12.5 19.0 19.5
60 M 42.3 21.4 43.8 23.6
60 M 25.2 25.4 24.7 15.9
60 M 12.6 17.8 18.5 15.5
60 F 29.4 26.4 25.3 36.5
60 F 36.4 36.5 46.8 24.9
60 F 18.9 18.3 21.2 17.6
60 F 17.2 15.9 15.8 20.6
70 M 36.2 32.4 23.9 33.1
70 M 11.9* 5.6 24.1 17.0
70 M 23.1 14.6 28.6 21.7
70 M 15.7 9.6 15.5 9.7
70 F 16.1 17.0 13.6* 21.2
70 F 22.5 20.5 25.4 22.4
70 F 11.1 9.5 9.6* 11.4
70 F 14.5* 14.7 10.4* 9.5*

 

*Subject was not able to remove the closure from the
instrumented bottle.

52

Table 21. Split-Plot Analysis of Variance performed on the
data from the Subject Downforce Measurements of
the human subject testing.

 

Source of Variation df F-Value
Total 127
Main Plot 17
Age 3 2.36*
Sex 1 0.43
Age x Sex 3 0.90
Error 1 24
Sub Plot 31
Closures 3 9.17***
Age x Closures 9 0.55
Sex x Closures 3 0.70
Age x Sex x Closures 9 0.70

Error 2 72

 

*significant at alpha = 0.10
**significant at alpha = 0.05
***significant at alpha = 0.01

53

Table 22. Tukey's Test performed on the Subject Downforce
Measurement data of the human subject testing,
looking for differences between the age groups.

 

Age Group Mean (pounds) Ranked Order
3 22.47 A
4 17.88 A
1 17.26 A
2 14.21 A

 

alpha = 0.05

Table 23. Tukey’s Test performed on the Subject Downforce
Measurement data, looking for differences
between the individual closures.

 

Closure # Mean (pounds) Ranked Order
3 19.75 A
1 19.54 A
4 18.26 A
2 14.26 B

 

alpha = 0.05

54
downforce to try to remove this closure type as compared
to the others. Closure 4 had a mean value of 18.26
pounds, followed by closure 1 at 19.54 pounds, and closure

3 at 19.75 pounds.

Preference Question

The Preference question was utilized to obtain a ranking
of the closures based on overall preference. The closures
were placed in the order of 1 through 4, a "1" meaning the
closure was the most preferred overall to a "4" used for
the closure least preferred overall. The experimental
design allowed for ties, which occurred four times. The

data can be found in Table 24.

The data was analyzed using Friedman’s Two-Way Analysis of
Variance. This technique is used to calculate two values;
R3 and sz. The Rj value is found by summing the data for
each of the closures. If all four closures are from the
same population the Rj values will be similar, and the
ranking of the closures just a matter of chance. If the

closures are from different populations the Ra'values will

55

Table 24. Data from the Preference (ranking) question
of the human subject testing.

Age Sex Closure #

1 2 3 4

 

35
35
35
35
35
35
35
35
50
50
50
50
50
50
50
50
6O
60
60
60
60
60
60
60
70
70
70
70
70
70
70
70

"i'll'q'flzgzg'fil'fl'fil"izzzzwm'fil'fizgzzq'fil'fl'fizzzz
han>b.H(pLuhoe-n.b.hcanoe.N.>bok>b.hrauibtohou)bIva:RJNiA
F'HthJUiHFJFOKDHEAFOR)H(»FJU)HFAFJKJHDAP4F3HQDFJP‘DPJAJ
tcfrouze-b.>+ucuoou)HIvrohauthbtnth.hhouibtvroaquk-bcn
b.5roespsNtnturdnoN>A.bcne>A)».bhonouiwwucuuibouLunauiw.>

 

*Subject was not able to remove the closure from the
test bottle.

56
be different. The Xr” value is used in comparison with a

chi square table, using k-l degrees of freedom, to test

whether the ijelues differ significantly.

The Friedman’s Two Way Analysis of Variance was first
calculated separating the male and female subjects to test
for an effect due to sex (Table 25). Both groups showed a
significant difference at a high level of confidence, the
males at 98% and females at 99.9%. This signifies that
both sexes felt that there was a significant difference
between the closures when ranked by overall preference,

and that this difference was not due to chance.

Looking at the calculated R3 for males and females,
closures 1, 3, and 4 have very similar values. Closure 2
has an Rj that is almost half of the other closures. This
appears to be the closure that the males and females felt
was different from the other closures. Closure 2 was the
most preferred overall by males and females, and there
were no apparent differences noted between the other three

closures for this question.

57

Table 25. Friedman’s Two-Way Analysis of Variance by
Ranks performed on the Preference question
data to look for an effect due to sex.*

 

 

Closure # Male Female
R: R:
l 43 43
2 26 22
3 46.5 46 5
4 44.5 48 5
sz 10.03 16.78
Confidence
Level** 98% 99.9%

*The male and female data was calculated separately to
determine if an effect due to sex group was evident.
Each sex group contained 16 subjects.

**This was determined by comparison with a chi square
table according to the Friedman's test.

58

Friedman's test was also used to check for any effects due
to the age groups tested (Table 26). Because there was
such a high level of agreement between the male and female
subjects, the sexes were combined into one group in each
age category. When looking at the sz values from this
calculation, all four age groups, at a confidence level of
90%, agree there is a significant difference between the
closures. Only age group 2, ages 46-55, showed a higher
level of confidence at 95%. This indicates that all the
age groups noticed a significant difference between the
closures for overall preference, and this was not due to

chance.

The R5 for closures l, 3, and 4 were in the same range for
all the age groups, but closure 2 was lower. All the age
groups noted a significant difference among the closures,
and this was due to closure 2. Closure 2 was the most
preferred overall, and with the highest confidence among

the age group of 46-55 year olds.

59
Table 26. Friedman’s Two-Way Analysis of Variance by
Ranks performed on the Preference question
data to look at a possible age group effect.

Age Groups*

 

 

Closure # 1 2 3 4
Rj Rj Rj R.

l 19 22 24 21

2 13 11 12 12

3 25 23.5 20 24.5

4 23 23.5 24 22 5
sz 6.3 8.21 7.2 6.86
Confidence
Level** 90% 95% 90% 90%

*The age group data was calculated separately to
determine if an effect due to age was evident.
Each age group contained eight subjects, four male
and four female. Group 1 contained subjects aged 25-45
years, group 2 was ages 46-55 years, group 3 was 56-65
years, and group 4 was ages 66-85 years.

**This was determined by comparison with a chi square
table according to the Friedman’s test.

60

General Trends

Although it is not possible to correlate the subject
downforce measurements to the machine minimum downforce
values due to different sample sizes, and a need to repeat
the experiment several times to validate such a
comparison, some general trends can be seen from the data.
Tukey’s Test on the subject downforce measurements (Table
23) shows closure 2 is different from the others, and has
a lower mean downforce value. The subjects used less
downforce when removing this closure as compared to the
others. Tukey’s Test on the machine minimum downforce
readings (Table 7) also showed closure 2 as different from
the others, and at a much lower mean value. A general
trend can be noted that both the subjects and the machine
testing revealed closure 2 as requiring the lowest amount

of downforce for a removal.

This may be due to the inner construction of that closure.
Closure 2 has a series of over 50 small angled ribs on the
outside wall of the inner shell, and the same angled ribs
on the inside wall of the outer shell (Figure 2).

Exerting a downforce causes these ribs to fit together and

61

Outer shell Inner shell

Top view Top view

0 0

Side view Side view

 

Milli!"llfllllllllllllllillllllll m

I .

 

 

Inner view

 

Figure 2. Inner construction of closure 2 (not drswn to scale).

62
allows a torque to be applied for a removal. Comparing
this construction; closure 1 has six projections on the
inside of the top of the outer shell that connect with
slots on the top of the inner shell when a downforce is
exerted (Figure 3). Six springs are also found on the
inside of the outer shell that connect with six slots on
the outside of the inner shell. The springs and slots
connect for a positive on, but the resistance of the
springs must also be overcome to connect the projections
for the removal. The downforce must be sufficient to keep
the protrusions engaged in the slots. If the downforce is
not sufficient or not maintained at the correct level the
protrusions will not stay engaged, and will slip out of
the slot. Closure 3 has 12 oblong ridges on the inside of
the outer shell that fit into 12 slots on the top of the
inner shell (Figure 4). If the downforce is not
sufficient or maintained, the ridges will not stay in the
slots, and the outer shell will ride over the inner shell.
Closure 4 has eight angled projections on the inside wall
of the outer shell that mesh with eight ridges on the
outside wall of the inner shell (Figure 5). Again, if the
downforce is not sufficient, the projections and ridges

will not mesh, and the outer shell will ride over the

63

 

Si

Nullllllmmwuumm l l

 

 

 

 

 

 

 

Outer shell
Top view

[lamumumuuunnnalum 5“" ”“1

 

 

 

 

 

 

\Ofl

COO

fl0\

Figure 4. Inner construction of closure 3 (not drewn to scsle).

65

Outer shell Inner shell
Top view Top view
Side view Side view

 

 

 

 

 

 

 

 

Nan“numummmuml C an

 

 

 

 

 

 

66

inner shell.

The number of points of connection within the inner and
outer shell may also contribute to the ability of subjects
to remove these closures. If the subject does not have
the required level of downforce, and there are only six
possible points of connection, he or she will have to
apply a torque and turn the closure farther if the first
attempt was unsuccessful to try another connection than if
the closure has over 50 possible connection points. This
can cause fatigue and frustration if several attempts must

be made.

Dimensional clearances and tolerances can be a factor that
will hinder the engagements of the two shells. If a ridge
is to be engaged into a slot, and the size of the slot is
very close to the size of the ridge, a successful
connection can be difficult to make and keep the parts
togetheru iFriction. between hard. materials and softer
materials can wear down edges and this can be enough to

prevent engagement.

67

Finally, it should. be :noted. that in all except seven
cases, the subjects tested were able to exert the maximum
amount of downforce necessary to remove the closures as
required according to the Auto-Torque tester. The results
from the testing showed closure 1 required a maximum of 10
pounds for a machine removal, while the subjects used up
to 42.3 pounds, with an average of 19.54 pounds. Closure
2 had a maximum machine downforce of 2 pounds, while the
subjects used up to 36.5 pounds, with an average of 14.26
pounds. Closure 3 required a machine maximum downforce of
12 pounds, while the subjects used up to 46.8 pounds, with
an average of 19.75 pounds. Finally closure 4 required a
maximum of 9 pounds for the machine removal, but the
subjects used up to 36.5 pounds, with an average of 18.26
pounds.

Comments of Test Participants

Most of the subjects tested did not understand how the
closures operated, and did not realize they were trying to
connect two shells when pushing on the closure. Many
specified that they disliked all push and turn closures,
but they realized that child-resistant closures performed

a necessary function in homes with young children. Others

68

said they would leave the containers open, or put their
medication. in another' package they could open easier.
Overall, much dissatisfaction with child-resistant

closures was noted.

CONCLUSIONS

The results from the analysis of the data allow several
conclusions to be made. The Machine Minimum Downforce
Measurements revealed. differences Ibetween three: of ‘the
four closures, with closure 2 significantly having the
lowest downforce value overall. The Acceptance and
Scaling questions, and the Subject Downforce Measurements
.all indicated an effect due to closure type tested. For
the Acceptance question, closure 1 and 2 had significantly
lower mean values, which indicates they were liked better.
Again closure 2 had the lowest mean value of the two. The
Scaling question showed closure 2 as different from the
others, at a mean value significantly lower. This
indicates that the subjects thought closure 2 was easier
to open. Additionally, the Subject Downforce Measurements
revealed closure 2 as different, with a mean value
significantly lower. This shows the subjects used less

downforce to remove that closure.

For the Preference question, Friedman’s analysis also

showed closure 2 as lower than the others, with no
69

70
significant effect due to sex or age group. Closure 2 was

ranked as being preferred more overall.

Examining these results indicate that closure 2 was rated
as better than any of the other closures. This may be due
to the inner construction as described in the Analysis of
Data section. It should be noted that this testing was
performed. with new closures, wear and ‘tear and other

factors may significantly change the results.

It should also be noted that as a general trend, the
majority of the subjects were all able to generate the
maximum necessary’ downforce to remove the closures as
determined by the machine testing. This indicates that
downforce alone may not be the inhibiting factor in the

closure removals.

RECOMMENDATIONS

This study can be a starting point for further research.
The bottles and closures tested were new, andghad never
been manipulated prior to the testing. It can be assumed
that normal wear and tear will affect the closures. And
although the Poison Prevention Packaging Regulations (Code
of Federal Regulations, 1987) state that the product
should not interfere with the special packaging, often
cough syrups or other sticky liquids can spill onto the
bottle finish area and interrupt the normal operation of

the closure.

The level of torque used to apply the closure may also
affect the downforce and removal torque necessary for a
successful removal. This can be important, as the level
of torque applied at the manufacturing site is assumed to
differ from that applied by a consumer who is reclosing

the container after usage.

A variation of this study would be to have subjects open

the closures and record the downforce to open, show the
71

72

subject the inner workings of the two shells and explain
how downforce operates to connect the shells, and have
them then remove another closure. This may help indicate
if educating consumers about the closures will have an
effect on their behavior when attempting a removal.

In this study children were not utilized for any of the
testing, and it may be desirable to do so in the future.
The closures require two dissimilar motions to achieve a
successful opening, and although children can perform
these motions independently, they do not usually have the
cognitive and/or motor ability to perform both motions
simultaneously. But information could still be gathered
as to the relative strength a child would exert for an

opening.

Lastly, it is recommended that more research be performed
on the instrumented bottle itself. The model used for
this testing was machined by hand by a relatively
inexperienced person. A more efficient design, or perhaps
one ‘with closer tolerances to the closures may yield’

results with an even better degree of accuracy.

BIBLIOGRAPHY

Anon.

Anon.

Anon .

Anon .

Anon .

Anon .

Anon.

Anon.

Arena,

BIBLIOGRAPHY

1988. Automated Dynamics Corporation, Auto-Torque
System, presented at the Michigan State University-
ASTM Seminar, East Lansing, MI, July 1988.

1988. Checking the Calibration of Torque Meters Used
in Packaging Applications D3474-80. ASTM,
Philadelphia, PA.

1970. Poison Prevention Packaging Act of 1970.
Child-Resistant Packaging. ASTM, Philadelphia,
PA.

1987. Poison Prevention Packaging Act of 1970
Regulations. Code of Federal Regulations 16
part 1000 to End. Commercial Practices.

Part 1700. US Government Printing Office,
Washington DC.

1988. Standard Classifications of Child-Resistant
Packaging D3475-83. .ASTM, Philadelphia, PA.

1987. Status Report of Grant Between the US
Consumer Product Safety Commission and the
Western Michigan University. Western Michigan
University, Kalamazoo, MI.

1988. Top-Load-to-Engage Removal Lugs on Type IA
Child-Resistant Closures D3471-82. ASTM,
Philadelphia, PA.

1985. The United States Pharmacopeia, Twenty-first
revision. United States Pharmacopeia Convention,
Inc. Rockville, MD.

Jay. 1970. The Need for Safety Packaging. Safety

Packaging in the ’70’s. The Proprietory
Association, New York, NY.

73

74

Berns, Tomas. 1981. The Handling of Consumer Packaging.
Applied Ergonomics. 12(3):153-161.

Dana, Margaret. 1975. Child-Resistant Packaging and
Consumer Reaction. Child-Resistant Packaging.
ASTM, Philadelphia, PA.

Jacobson, Barbara J, Amy R. Rock, and Murray S. Cohn.
1989. Preliminary Report of the Prescription Drug
Ingestion Study to the Consumer Product Safety
Commission, Rockville, MD.

Krogman, Wilton M. 1970. Engineering Standards
Development-Manual and Oral Strength in Children
Ages 3 to 6 Years. Safety Packaging in the '70's.
The Proprietory Association, New York, NY.

Little, Thomas M. and F. Jackson Hills. 1978. Agricultural
Experimentation Design and Analysis. John Wiley &
Sons, New York, NY.

Lockhart, H.E., Susan Selke, Lisa Hewartson, Beth Waggoner.
1988. Innovative Child Resistant Packaging Systems,
Final Report to the CPSC. Michigan State University,
East Lansing, MI.

MacArthur, M.D. 1988. Product Safety Features Under US
Agency Scrutiny. Paper, Film & Foil Converter.
62(8):66.

Maisel, 6.8. 1975. Poison Prevention Packaging - A
Retrospective View. Child-Resistant Packaging.
ASTM, Philadelphia, PA.

Meilgaard, Morten, Gail Vance Civille, and B. Thomas Carr.
1987. Sensory Evaluation Techniques, VOlume I.
CRC Press, Boca Raton, FL.

Perritt, A.M. 1975. Protocol for the Evaluation of Poison
Prevention Packaging. Child-Resistant Packaging.
ASTM, Philadephia, PA.

Press, Edward. 1970. Appendix 1: Resume-Report of the
Joint Industry-FDA Committee on Safety Closures.
Safety Packaging in the '70’s. The Proprietory
Association, New York, NY.

75

Rider, Barbara, Brian Akers, Donald Blasch, and Robert
Brashear. 1987. Product Packaging Difficulties of
the Handicapped and Elderly. Michigan Academissions,
Summer 1987. Vbl. XIX, No. 3. Western Michigan
University, Kalamazoo, MI.

Sacharow, Stanley. 1988. Lessons of History. Packaging
Week. July 13, 1988. 4(10):l4.

Sharma, Jayesh. 1987. A Study of Human Factors in Child-
Resistant Packaging. MS thesis. Western Michigan
University, Kalamazoo, MI.

Siegel, Sidney. 1956. Nonparmetric Statistics for the
Behavioral Studies. McGraw-Hill Book Company,
Inc., New York, NY.

Steel, Robert G.D. and James H. Torrie. 1980. Principles
and Procedures of Statistics. McGraw-Hill Book
Company, Inc., New York, NY.

Tainter, Maurice L. 1970. The Realities of Safety
Packaging. Safety Packaging in the ’70's. The
Proprietory Association, New York, NY.

Thein, W.M.A. and W.H.J. Rogmans. Testing Child
Resistant Packaging for Access by Infants and the
Elderly. Accidental Analysis and Prevention.
16(3). Pergamon Press Ltd.

VanGieson, Paul. 1983. ASTM's History in Child-Resistant
Packaging. ASTM Standardization News. ASTM,
Philadelphia, PA.

Verhulst, Henry L. 1970. Why Safety Packaging? Safety
Packaging in the '70’s. The Proprietory
Association, New York, NY.

APPENDICES

APPENDIX A

76

Appendix A

Table l. Subject's bottle* and closure** grips used when
removing closure #1.

 

Subject # Test Bottle*** Instrumented Bottle****
Closure Bottle Closure Bottle
1 F T F T
2 F T F T
3 P T P T
4 F 1 F 1
5 F 1 F 1
6 F T F T
7 M 1 M T
8 F 1 F 1
9 F T F 1
10 F 1 F l
11 P T P T
12 F 1 F 1
13 F 1 F 1
14 F T F T
15 F 1 F 1
16 F T F T
17 P 0 P 0
18 F 1 F 1
19 P T P T
20 P T P T
21 P 2 P 1
22 P T P T
23 P T P T
24 P 1 P l
25 P T P T
26 P 1 P 1
27 P T P T
28 P T P T
29 P 0 P 0
30 P 1 P 1

 

77

Table 1. continued

 

Subject # Test Bottle Instrumented Bottle

Closure Bottle Closure Bottle
31 P 1 P 1
32 P 1 P 1
33 P 1 P 1
34 P 1 P 1
35 P T P T
36 P 1 P 1
37 F 1 F 1
38 P 1 P T
39 P T P T
40 P 1 P 1
41 P 1 P 1

 

*Bottle grips coding: T - Bottle placed on table
L - Bottle placed against leg
0 - All four fingers grasp bottle,
no fingers underneath for

support

1 - One finger under bottle for
support

2 - Two fingers under bottle for
support

**Closure grip coding: F - Fingers grasp closure in a form
of a pincher grip
P - Palm of hand is applied to top
of closure
M - Multiple grips were used by the
subject

***Test Bottle: This closure/bottle system was used for the
subject when answering the Acceptance, Scaling, and
Preference Questions.

****Instrumented Bottle: This closure/bottle system was
used to measure downforces exerted by subjects.

78
Table 2. Subject's bottle* and closure** grips used when
removing closure #2.

Subject # Test Bottle*** Instrumented Bottle****
Closure Bottle Closure Bottle

 

$004030!»me

H

q
mroruvoromro'omtorovorummrommmmmmmmmmmzzuimmmmm
HHHHHHOHHHHHHHHHHHHHHI—JHHHHHOHHHHHHH
rovororowmwmroro'o'o'uroro'ororommmmmmwmwzz'dmmmmm
HHl—‘HHHOh—BI-it-‘HI—‘O-Jt-lHHHHHHHHHHHHHOHHHHHHH

 

79

Table 2. continued

 

Subject # Test Bottle Instrumented Bottle

Closure Bottle Closure Bottle
36 P 1 P 1
37 P 1 P l
38 P T P T
39 P L P L
40 P 1 P 1
41 P 1 P 1

 

*Bottle grips coding: T - Bottle placed on table
L - Bottle placed against leg
0 - All four fingers grasp bottle,
no fingers underneath for

support

1 - One finger under bottle for
support

2 - Two fingers under bottle for
support

**Closure grip coding: F - Fingers grasp closure in a form
of a pincher grip
P - Palm of hand is applied to top
of closure
M - Multiple grips were used by the
subject

***Test Bottle: This closure/bottle system was used for the
subject when answering the Acceptance, Scaling, and
Preference Questions.

****Instrumented Bottle: This closure/bottle system was
used to measure downforces exerted by subjects.

80
Table 3. Subject’s bottle* and closure** grips used when
removing closure #3.

Subject # Test Bottle*** Instrumented Bottle****
Closure Bottle Closure Bottle

 

\DmQOSUIobUNH

H
q
romrururorurororurommwmrorommmmmmmmwwmmzmwmwmm
HHHHHI—‘OHHHHHHHHHHNOHHHHHHHHHHHHHHHH
'U'U'UFU'U'U'U'U'U'U'U'U'O'U'II'U'U'I!NWWWWMMWMWZWWMNMM
HI—‘l—‘l—‘l—‘l—‘OHHHHHHHOHHHOHHHHHHHHHHHHHHHH

 

81

Table 3. continued

 

Subject # Test Bottle Instrumented Bottle
Closure Bottle Closure Bottle
36 P 1 P 1
37 F 1 F 1
38 P 1 P 1
39 P L P L
40 P 1 P 1
41 P 1 P 1

 

*Bottle grips coding: T - Bottle placed on table
L - Bottle placed against leg
0 - All four fingers grasp bottle,
no fingers underneath for

support

1 - One finger under bottle for
support

2 - Two fingers under bottle for
support

**Closure grip coding: F - Fingers grasp closure in a form
of a pincher grip
P - Palm of hand is applied to top
of closure
M - Multiple grips were used by the
subject

***Test Bottle: This closure/bottle system was used for the
subject when answering the Acceptance, Scaling, and
Preference Questions.

****Instrumented Bottle: This closure/bottle system was
used to measure downforces exerted by subjects.

82
Table 4. Subject’s bottle* and closure** grips used when
removing closure #4.

Subject # Test Bottle*** Instrumented Bottle****
Closure Bottle Closure Bottle

 

\OCDQOSUIowaH

H
on
rumrororurorororororororurorovomommmmmmmmmmzmwujmmm
HHHHHHOHHHHHHHOHHHHHHHOHHHHHHHHHHHH
rupturerarererumwroru'orororomommmmmwmmmwzmmmmmm

HHr-JHHl-‘Oi-ll-‘i-‘HHF-lt-ElNHHHHHHHOHHHHHHHHHHHH

 

83

Table 4. continued

 

Subject # Test Bottle Instrumented Bottle

Closure Bottle Closure Bottle
36 P 1 P l
37 F 1 F 1
38 P l P T
39 P L P T
40 P 1 P 1
41 P l P 1

 

*Bottle grips coding: T - Bottle placed on table
L - Bottle placed against leg
0 - All four fingers grasp bottle,

no fingers underneath for

support

1 - One finger under bottle for
support

2 - Two fingers under bottle for
support

**Closure grip coding: F - Fingers grasp closure in a form
of a pincher grip
P - Palm of hand is applied to top
of closure
M — Multiple grips were used by the
subject

***Test Bottle: This closure/bottle system was used for the
subject when answering the Acceptance, Scaling, and
Preference Questions.

****Instrumented Bottle: This closure/bottle system was
used to measure downforces exerted by subjects.

APPENDIX B

84

APPENDIX B

Human Subject Questionnaire

Date Page 1
Subject 0 ________

CHILD RESISTANT PACKAGE TESTING

I am studying problems that adults have when opening certain child resistant
packages. You will be asked to open tour containers, and to fill out a short
questionnaire.

This test should take about 15 minutes. You are free to end the test at any
time. You are free to not answer any of the questions, and to ask if you need
a clarification at any time.

Your identity will be kept in strict confidence. The data from this test will
be used to identify problems with push and turn child resistant closures.

Thank you for your cooperation and participation.

Age / _/ 25-45 /::7 46-55 /:-7 ss-ss 1::7 65-75 /::7 76+

Sex /__/ n /__/ F

Right Handed I / Lett Handed I /

Do you believe you have any physical lieitations which may make these
packages difficult for you to open or close?

Are you faeilar with this kind of push and turn child resistant packages?

Yes I I No I

If yes, which products or product types have you used that have this child
resistant teature incorporated into the package?

I I Antitreeee or other autoeotivp products
I I Vitaeins or diet supplieents

I I Cleaning products

I I Herbicides

I I Prescription drugs

I I Pain relievers

I I Other , please speciiy

 

85

DATA SHEET Page 2

Date

 

Subject I ..........

We are studying four different aspects of child resistant closures, using

four different test closures that have been labeled “514', ”127”, “285“, and
"329” for identification purposes. Please choose one from the bag and open and
close it, then rate it on the scales on pages 2 and 3. When you have finished,
I will have you remove the same closure one more tine with a different bottle.
I will then have you choose another sample fro. the bag, and continue until all
have been tested.

Please rate each test sample, immediately after opening, by placing a mark
on the line corresponding to the ease of opening.

EASE OF OPENING

Closure # Scale

Very easy _ Very hard
to open to open

AL

——----e—-

 

 

DATA SHEET Page 3
Date
Subject I __ ______
Please rate each test closure, immediately after opening, on how well you liked
it.
How wELL vou LIKED EACH CLOSURE

Closure _____ CIDSUVO -..--
Extremely well liked /::7 Extrsssly well liked 1::7
Liked very much I::7 Liked very much I::7
Moderately liked /::I Moderately liked I::7
Slightly liked /::7 Slightly liked /::7
Neither liked nor ___ Neither liked nor ___
disliked /-_/ disliked /__/
Slightly dislike /::7 Slightly dislike /::7
Moderately dislike I::7 Moderately dislike I::7
Dislike very much /::7 Dislike very such I::7
Extremely dislike /::7 Extremely dislike 1::-

Closure _____ CIOSUFC ..---
Extremely well liked /::7 Extrsssly well liked 1::7
Liked very much /::7 Liked very euch /::7
Moderately liked I::7 Moderately liked /::7
Slightly liked /::7 Slightly liked /::-
Neither liked nor _. Neither liked nor -__
dislike /__I dislike I__I
Slightly dislike 12:7 Slightly dislike 1::7
Moderately dislike I::- Moderately dislike /::7
Dislike very much /::I Dislike very much I::7
Extremely dislike /"7 Extreeely dislike /"7

 

DATA SHEET

Date

 

Subject fl _______

Please compare the four closures by opening then,
order of which one you prefer overall,

87

RANKING

Page 4

and then placing them in the

to the one you least prefer overall.

Place the number of the closure you prefer overall next to the *1 space, and
continue, placing the closure number you least preferred on the #4 space.

Preferred closure

*1

93

”4

 

 

 

88

 

 

 

 

 

 

 

 

 

 

 

DATA SHEET

Date

Subject * ........

Closure Force Chart Hand Comments
reading Reading Position
(a) (b)

 

 

 

 

(a) initial force reading
(b) maximum force reading

APPENDIX C

89

Appendix C

Table 8. Subjects listed by age group and sex.

 

29**
30**

Subject # Age Group* Sex
1 4 F
2 3 F
3 3 F
4 3 M
5 4 M
6 4 F
7 1 F
8 1 F
9 1 F

10 1 F
11 3 F
12 1 M
13 2 M
14 1 M
15 3 M
16 1 M
17 3 F
18 1 M
19** 1 F
20 2 M
21 2 F
22** 3 F
23 3 M
24 2 M
25 3 M
26** 3 F
27 2 F
28** 3 F

3 M

3 M

 

90

Table 8. continued

 

Subject # Age Group Sex
31** 3 F
32 2 F
33** 1 F
34 4 M
35 4 F
36 2 F
37 2 M
38 4 F
39 4 M
40 4 M
41** 4 F

 

*Age Groups 1 - ages 25-45
2 - ages 46-55
3 - ages 56-65
4 - ages 66-85

**The data from these subjects was not used in the
data analysis, these were tested as alternates
in case problems were encountered.

APPENDIX D

91

Appendix D

Raw data from the Acceptance Question.

9.

Table

Subject #

Closure #

 

3375796238743

1394398224371

2283712722422

3364536822633

1234567890123
1111

3732525696223563527168

4757345235224775395378

2443632163226223324143

6648322426272484496157

14
15
16
17
18
19
20
21

22

23
24

25
26
27

28
29
30
31

32

33
34

35

 

92

Table 9. continued

 

Subject # Closure #

1 2 3 4
36 2 3 2 2
37 5 2 2 4
38 3 1 9 9
39 6 2 8 4
40 2 l 2 l
41 7 7 9 4

 

93

Raw data from the Scaling Question (1/10").

10.

Table

Subject #

Closure #

 

3&929nw5/m—J8
nU.131n/“53nwnv.

30.11316—/.—.D.
nU.151nm54nU.O.

34571~/.SAU.4
nwnU.40.3nwnw5nw

.3.878519nU.5
O.nU.311126nu.

123456789

16944893928471812588810195
53135400011555011232205035

18117938019997199974584148
20333413241.003100343154344

43531887315488881853516123
01022200021032000001101021

19939489724041176266773147
12033304111305140252154034

21
22
23
24
25
26
27
28
29
30
31
32
33
34
35

 

94

continued

Table 10.

Closure #

Subject #

 

62754
01520

42733
10551

53123
00010

34743
11131

36
37
38
39
40
41

 

95

Raw data from the Preference Question.

11.

Table

Closure #

Subject #

3

 

22233431344332241313444342242322334

23321342431443333143331224323243443

21112213112121122421113121111111111

44444124223214414232222423434434222

12345678901234567890
11111111112

 

96

Table 11. continued

 

Subject # Closure #
1 2 3 4
36 2 3 1 4
37 3 1 4 2
38 2 l 4 4
39 3 1 4 2
40 3 2 4 1
41 2 3 4 1

 

97

 

Table 12. Raw data from the Subject Downforce
Measurements (lbs).
Subject # Closure #
1 2 3 4
1 22.5 20.5 25.4 22.4
2 18.9 18.3 21.2 17.6
3 36.4 36.5 46.8 24.9
4 25.2 25.4 24.7 15.9
5 36.2 32.4 23.9 33.1
6 16.1 17.0 13.6 21.1
7 30.0 23.4 42.1 27.0
8 20.3 17.5 23.2 13.4
9 15.5 9.6 17.2 18.2
10 16.6 12.5 15.6 16.1
11 29.4 26.4 25.3 36.5
12 21.2 13.3 15.5 17.8
13 7.6 8.5 14.9 13.5
14 22.0 13.0 11.0 14.4
15 14.3 12.5 19.0 19.5
16 16.9 11.2 21.3 13.4
17 17.2 15.9 15.8 20.6
18 19.6 6.0 22.6 15.0
19 18.2 20.6 34.1 23.9
20 21.8 12.7 10.1 23.7
21 13.3 9.4 13.4 16.5
22 19.6 14.5 16.9 23.2
23 42.3 21.4 43.8 23.6
24 17.3 12.3 8.6 19.1
25 12.6 17.8 18.5 15.5
26 17.0 15.1 18.6 14.1
27 9.5 9.4 19.6 16.1
28 29.6 19.4 31.5 39.4
29 21.6 9.0 13.4 12.9
30 14.2 25.1 23.6 8.0
31 4.1 8.0 12.0 12.5
32 26.4 18.1 21.1 21.9
33 24.4 12.9 23.6 19.1
34 11.9 5.6 24.1 17.0
35 11.1 9.5 9.6 11.4

 

98

 

Table 12. continued
Subject # Closure #
1 2 3 4

36 18.4 4.2 16.6 12.9
37 12.4 5.5 13.3 6.6
38 14.5 14.7 10.4 9.5
39 23.1 14.6 28.6 21.7
40 15.7 9.6 15.5 9.7
41 17.9 17.6 15.2 25.9

 

"Iliiflllljllllllllll@1171“