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Home > About USPS & News > Forms & Publications > Postal Periodicals and Publications > Publications > Publication 2 - Packaging for Mailing > Appendix A Package Testing > Procedure
Prior to beginning the tests identify the faces, edges and corners according to
the procedure below.
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Step
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Action
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1
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Place the packaged-product in its intended shipping position as determined
by shipper. If the shipping position can be variable, place the
packaged-product so that the primary shipping label location is on the top
face.
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2
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Does the packaged-product have only six faces (2 sides, 2 ends, top and
bottom)?
• If Yes, then go to Step 5.
• If No, continue to next Step.
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3
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Develop a method to identify each face, edge and corner and document with
a diagram.
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4
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Go to the next Block.
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5
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Is the package a corrugated container?
• If Yes, continue to next Step.
• If No, then go to Step 8.
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6
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Does the package have a manufacurer's joint connecting a side and an end
face?
• If Yes, continue to next Step.
• If No, then go to Step 8.
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7
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Turn the packaged-product so that you are looking directly at a face with the
manufacturer's joint on the observer's right and go to Step 9.
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8
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Position one of the smallest width faces of the packaged-product directly in
front of you.
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9
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blank |
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10
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Identify edges using the numbers of the two faces forming that edge.
Example: Edge 1-2 is the edge formed by face 1 and face 2 of the
packaged-product.
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11
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Identify corners using the numbers of the three faces that meet to form that
corner.
Example: Corner 2-3-5 is the corner formed by face 2, face 3, and face 5 of
the packaged-product.
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12
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Go to next Block.
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You shall know the packaged-products:
• gross weight in pounds (kg) rounded up to a whole number, and
• outside dimensions of Length, Width, and Height (L x W x H) in inches
(mm or m).
Caution: A restraining device or devices shall be used with the vibration test
system to:
• Prevent the test specimen from moving off the platform and
• Maintain test orientation of the packaged-product, but
• The device or devices shall not restrict the vertical motion of the test
specimen during the test.
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Step
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Action
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1
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Familiarity with the following formula is required to calculate
the test duration after the frequency required to bounce the
packaged-product is determined in the Vibration Test Block:
Test Duration in Minutes = 14, 200 Vibratory Impacts
Cycles Per Minute (CPM) or
[Cycles Per Second (Hz) x 60]
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2
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The chart below shows example Test Durations calculated for
several frequencies:
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CPM
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Hz
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Test Duration in Minutes
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150
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2.5
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95
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180
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3.0
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79
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210
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3.5
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68
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| blank |
240
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4.0
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60
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| blank |
270
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4.5
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53
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| blank |
300
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5.0
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48
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The table below indicates the steps to perform a Fixed Displacement
Vibration Test.
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Step
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Action
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1
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Put the packaged-product on the vibration table so that face 3 rests on the
platform.
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2
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Start the vibration system to vibrate at 1.0 inches (25 mm) total displacement
at the machine's lowest frequency.
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3
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Maintain a fixed displacement at 1 inch (25 mm) and slowly increase the
frequency (speed) of the vibration table until the packaged-product begins to
momentarily leave the surface of the platform.
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4
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Hold the vibration frequency to that determined in Step 3.
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5
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Can a metal shim be intermittently moved between the bottom of the longest
dimension of the packaged-product and the surface of the platform?
• If Yes, hold that frequency and then continue to next Step.
• If No, then increase the frequency until the requirement of Step 5 is met
and hold that vibration frequency.
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6
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Determine the test duration in minutes using the formula indicated in the
Before You Begin Block and the CPM or Hz frequency identified in Step 5.
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7
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Begin the vibration duration.
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8
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Are you using a vertical linear motion on the vibration system?
• If Yes, then go to Step 12.
• If No, then continue with the next Step.
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9
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Stop the vibration test halfway throught the vibration duration and perform the
appropriate action as indicated below:
• IF a single 90° horizontal rotation is possible, THEN perform a horizontal
rotation of 90° as the specimen rests on the platform.
• IF a single 90° horizontal rotation is not practical because of the size of
the packaged-product or the stability of the packaged-product, THEN
perform a horizontal rotation of 180° as the specimen tests on the
platform.
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10
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Start the vibration system and continue the vibration test at the frequency
used in Step 7.
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11
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Can a metal shim be intermittently moved between the bottom of the longest
dimension of the packaged-product and the surface of the platform?
• If Yes, then continue to next Step.
• If No, then slowly increase the frequency until the requirement of Step 11
is met.
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12
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Complete vibration duration.
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13
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Inspection of the packaged-product for visible damage is allowed, provided
inspection does not alter, in any way, the current condition of the package or
the condition or position of the product(s).
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14
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Vibration testing is now complete. Go to the Shock Test Block.
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The test drop height varies with the weight of the packaged-product. Find the
weight of the packaged-product in the following chart to determine a drop
height or an equivalent impact velocity to be used for a substituted drop:
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Packaged-Product Weight
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Drop Height
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Impact Velocity
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Equal to or greater than
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But Less than
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Free Fall
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Incline or Horizontal
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lb
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kg
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lb
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kg
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In.
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mm
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ft/s
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m/s
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0
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0
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21
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10
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30
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760
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13
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3.9
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21
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10
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41
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19
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24
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610
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11
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3.4
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41
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19
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61
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28
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18
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460
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10
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3.0
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61
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28
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100
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45
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12
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310
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8.0
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2.5
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100
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45
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150
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68
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8
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200
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6.6
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2.0
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The test method requires the packaged-product to be dropped in several
different package orientations.
A drop test must be performed in all required orientations where dropping the
packaged-product is practical.
If dropping in a required orientation is not practical an equivalent incline or
horizontal test can be substituted for that orientation.
When using impact velocity, if any test in a Test Sequence is below the
required minimum level, that sequence event must be repeated until the test
impact velocity meets the minimum.
The table below indicates the steps to perform the Drop Shock Test.
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Step
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Action
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1
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Determine the method(s) of test and the required drop height or impact
velocity in the Before You Begin Block.
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2
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Do you have a packaged-product with only 6 faces as identified in the Face,
Edge and Corner Identification Block?
• If Yes, continue with the next Step.
• If No, then go to Step 6.
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3
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Test the packaged-product according to the method(s) and level(s)
determined in Step 1. Follow the sequence in the table below.
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4
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Sequence #
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Orientation
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Specific face, edge or corner
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1
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Corner
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most fragile face-3 corner, if not known,
test 2-3-5
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2
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Edge
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shortest edge radiating from the corner
tested
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3
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Edge
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next longest edge radiating from the
corner tested
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4
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Edge
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longest edge radiating from the corner
tested
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5
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Face
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one of the smallest faces
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6
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Face
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opposite small face
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7
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Face
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one of the medium faces
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8
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Face
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opposite medium face
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9
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Face
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one of the largest faces
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10
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Face
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opposite large face
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5
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All testing is now complete. Go to the Test Report Block.
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6
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Select a bottom face corner to replace the corner required in Step 4
Sequence 1 to begin the test.
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7
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Identify the edges of the packaged-product that meet the Step 4 Sequence
2 through 4 requirements.
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8
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Select any 6 faces to replace the faces required in Step 4 Sequence 5
through 10.
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9
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Using the corner, edges and faces from Steps 6 through 8 go to Step 3 and
proceed.
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10
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All testing is now complete. Go to the Test Report Block.
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