ASTM D4728-95

NOTICE: This standard has either been superseded and replaced by a new version or
withdrawn. Contact ASTM International (www.astm.org) for the latest information.
Designation: D 4728 – 95
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Method for
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Random Vibration Testing of Shipping Containers
This standard is issued under the fixed designation D 4728; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.2 Definitions of Terms Specific to This Standard:
3.2.1 bandwidth—the difference, in Hz, between the upper
1.1 This test method covers the random vibration testing of
and lower limits of a frequency band. For the purposes of this
filled shipping units. Such tests may be used to assess the
test method, the bandwidth may be considered equivalent to
performance of a container with its interior packing and means
the frequency resolution of a spectrum analysis.
of closure in terms of its ruggedness and the protection that it
3.2.2 closed-loop—a condition of control where the input
provides the contents when subjected to random vibrational
may be modified over time by the effect of the output or
inputs.
response of the system.
1.2 This test method provides guidance in the development
and use of vibration data in the testing of shipping containers. 3.2.3 decibel (dB)—ten times the base 10 logarithm of a
1.3 Two alternative vibration control techniques are de- ratio of two power like quantities that is, a PSD. Two PSD
scribed as follows: levels that have a ratio of 2.0 differ by 3 dB. Two PSD levels
1.3.1 Method A Closed Loop—Automatic Equalization that have a ratio of 0.5 differ by −3 dB.
(5.2.1, 10.2.1) 3.2.4 equalization—adjustment or correction of the ampli-
1.3.2 Method B Open Loop—Data Storage Media (5.2.2,
tude characteristics of an electronic control signal throughout a
10.2.2) desired frequency range to maintain a desired vibration output
spectrum and level.
NOTE 1—Sources of supplementary information are listed in the Ref-
2
3.2.5 equalizer—instrumentation used to conduct equaliza-
erence section (1–10).
tion.
1.4 This standard does not purport to address all of the
3.2.6 mean-square—the time average of the square of a
safety concerns, if any, associated with its use. It is the
function.
responsibility of the user of this standard to establish appro-
3.2.7 open loop—a condition of control where the input of
priate safety and health practices and determine the applica-
a system is preestablished and is not affected by the output or
bility of regulatory limitations prior to use. Specific safety
response of the system.
hazard statements are given in Section 6.
3.2.8 overall g rms—the square root of the integral of power
2. Referenced Documents
spectral density over the total frequency range.
3.2.9 periodic vibration—an oscillation whose waveform
2.1 ASTM Standards:
repeats at equal increments of time.
D 996 Terminology of Packaging and Distribution Environ-
3
ments 3.2.10 power spectral density (PSD)—an expression of
D 4169 Practice for Performance Testing of Shipping Con- random vibration in terms of mean-square acceleration per unit
2 2
3
tainers and Systems of frequency. The units are g /Hz (g /cycles/s). Power spectral
D 4332 Practice for Conditioning Containers, Packages or density is the limit of the mean square amplitude in a given
3
Packaging Components for Testing rectangular band divided by the bandwidth, as the bandwidth
approaches zero.
3. Terminology
3.2.11 random vibration—an oscillation whose instanta-
3.1 Definitions:
neous amplitude is not prescribed for any given instant in time.
3.1.1 General—Definitions for the packaging and distribu-
The instantaneous amplitudes of a random vibration are
tion environments are found in Terminology D 996.
prescribed by a probability distribution function, the integral of
which over a given amplitude range will give the probable
percentage of time that the amplitude will fall within that
1
This test method is under the jurisdiction of ASTM Committee D-10 on
range. Random vibration contains no periodic or quasi-periodic
Packaging and is the direct responsibility of Subcommittee D10.22 on Handling and
constituent. If random vibration has instantaneous magnitudes
Transportation.
Current edition approved Nov. 10, 1996. Published January 1995. Originally
that occur according to the Gaussian distribution, it is called
published as D-10 Proposal P 186. Last previous edition D 4728 – 91.
“Gaussian random vibration.” Gaussian random vibration has
2
The boldface numbers in parentheses refer to the list of references at the end of
the property that the rms level is equal to the standard
this tes
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