Testing the integrity of the containment system and shielding and evaluating criticality safety

After each of the applicable tests specified in 6.4.15 to 6.4.21:
(a) Faults and damage shall be identified and recorded;
(b) It shall be determined whether the integrity of the containment system and shielding has been
retained to the extent required in 6.4.2 to 6.4.11 for the package under test; and
(c) For packages containing fissile material, it shall be determined whether the assumptions and
conditions used in the assessments required by 6.4.11.1 to 6.4.11.14 for one or more packages
are valid.

 

Target for drop tests

The target for the drop tests specified in 2.2.7.2.3.3.5 (a), 6.4.15.4, 6.4.16 (a), 6.4.17.2 and 6.4.20.2
shall be a flat, horizontal surface of such a character that any increase in its resistance to displacement
or deformation upon impact by the specimen would not significantly increase the damage to the
specimen.

Tests for demonstrating ability to withstand normal conditions of carriage

The tests are: the water spray test, the free drop test, the stacking test and the penetration test.
Specimens of the package shall be subjected to the free drop test, the stacking test and the penetration
test, preceded in each case by the water spray test. One specimen may be used for all the tests,
provided that the requirements of 6.4.15.2 are fulfilled.

The time interval between the conclusion of the water spray test and the succeeding test shall be such
that the water has soaked in to the maximum extent, without appreciable drying of the exterior of the
specimen. In the absence of any evidence to the contrary, this interval shall be taken to be two hours if
the water spray is applied from four directions simultaneously. No time interval shall elapse, however,
if the water spray is applied from each of the four directions consecutively.

Water spray test: The specimen shall be subjected to a water spray test that simulates exposure to
rainfall of approximately 5 cm per hour for at least one hour.

Free drop test: The specimen shall drop onto the target so as to suffer maximum damage in respect  
of
the safety features to be tested.
 
(a) The height of drop measured from the lowest point of the specimen to the upper surface of the 
target shall be not less than the distance specified in Table 6.4.15.4 for the applicable mass.  
The target shall be as defined in 6.4.14;
 
(b) For rectangular fibreboard or wood packages not exceeding a mass  of  50 kg,  a  separate 
specimen shall be subjected to a free drop onto each corner from a height of 0.3 m;
 
(c)     For cylindrical fibreboard packages not exceeding a mass of 100 kg, a separate specimen 
shall  be subjected to a free drop onto each of the quarters of each rim from a height of 0.3 m.
 
Table 6.4.15.4:     Free drop distance for testing packages to normal conditions of carriage
 
 

Package mass (kg)

Free drop distance (m)

Package mass < 5 000

1.2

5 000  Package mass < 10 000

0.9

10 000  Package mass < 15 000

0.6

15 000  Package mass

0.3

 

Stacking test: Unless the shape of the packaging effectively prevents stacking, the specimen shall be
subjected, for a period of 24 h, to a compressive load equal to the greater of the following:
(a) The equivalent of 5 times the maximum weight of the package; and
(b) The equivalent of 13 kPa multiplied by the vertically projected area of the package.
The load shall be applied uniformly to two opposite sides of the specimen, one of which shall be the
base on which the package would typically rest.

Penetration test: The specimen shall be placed on a rigid, flat, horizontal surface which will not move
significantly while the test is being carried out.
(a) A bar of 3.2 cm in diameter with a hemispherical end and a mass of 6 kg shall be dropped and
directed to fall, with its longitudinal axis vertical, onto the centre of the weakest part of the
specimen, so that, if it penetrates sufficiently far, it will hit the containment system. The bar
shall not be significantly deformed by the test performance;
(b) The height of drop of the bar measured from its lower end to the intended point of impact on
the upper surface of the specimen shall be 1 m.

Additional tests for Type A packages designed for liquids and gases

A specimen or separate specimens shall be subjected to each of the following tests unless it can be
demonstrated that one test is more severe for the specimen in question than the other, in which case
one specimen shall be subjected to the more severe test.
(a) Free drop test: The specimen shall drop onto the target so as to suffer the maximum damage in
respect of containment. The height of the drop measured from the lowest part of the specimen
to the upper surface of the target shall be 9 m. The target shall be as defined in 6.4.14;
(b) Penetration test: The specimen shall be subjected to the test specified in 6.4.15.6 except that the
height of drop shall be increased to 1.7 m from the 1 m specified in 6.4.15.6 (b).

Tests for demonstrating ability to withstand accident conditions in carriage

The specimen shall be subjected to the cumulative effects of the tests specified in 6.4.17.2
and 6.4.17.3, in that order. Following these tests, either this specimen or a separate specimen shall be
subjected to the effect(s) of the water immersion test(s) as specified in 6.4.17.4 and, if applicable,
6.4.18.

 
Mechanical test: The mechanical test consists of three different drop tests. Each specimen shall be 
subjected to the applicable drops as specified in 6.4.8.8 or 6.4.11.13. The order in which the 
specimen is subjected to the drops shall be such that, on completion of the mechanical test, the 
specimen shall have suffered such damage as will lead to the maximum damage in the thermal test 
which follows.
 
(a)    For drop I, the specimen shall drop onto the target so as to suffer the maximum damage, and  
   the height of the drop measured from the lowest point of the specimen to the upper surface of 
the target shall be 9 m. The target shall be as defined in 6.4.14;
 
(b)    For drop II, the specimen shall drop onto a bar rigidly mounted perpendicularly on the 
target so as to suffer the maximum damage. The height of the drop measured from the intended point 
of impact of the specimen to the upper surface of the bar shall be 1 m. The bar shall be of solid 
mild steel of circular section, (15.0 cm ± 0.5 cm) in diameter and 20 cm long unless a longer bar 
would cause greater damage, in which case a bar of sufficient length to cause maximum damage shall 
be used. The upper end of the bar shall be flat and horizontal with its edge rounded off to a 
radius of not more than 6 mm. The target on which the bar is mounted shall be as described in 
6.4.14;
 
(c) For drop III, the specimen shall be subjected to a  dynamic  crush  test  by  positioning  the 
specimen on the target so as to suffer maximum damage by the drop of a 500 kg mass from      9 m 
onto the specimen. The mass shall consist of a solid mild steel plate 1 m by 1 m and shall fall in 
a horizontal attitude. The lower face of the steel plate shall have its edges and corners rounded 
off to a radius of not more than 6 mm. The height of the drop shall be measured from the underside 
of the plate to the highest point of the specimen. The target on which the specimen rests shall be 
as defined in 6.4.14.
 

Thermal test: The specimen shall be in thermal equilibrium under conditions of an ambient
temperature of 38 °C, subject to the solar insolation conditions specified in Table 6.4.8.6 and subject
to the design maximum rate of internal heat generation within the package from the radioactive
contents. Alternatively, any of these parameters are allowed to have different values prior to and
during the test, providing due account is taken of them in the subsequent assessment of package
response.
 
The thermal test shall then consist of:
(a) Exposure of a specimen for a period of 30 minutes to a thermal environment which provides a
heat flux at least equivalent to that of a hydrocarbon fuel/air fire in sufficiently quiescent
ambient conditions to give a minimum average flame emissivity coefficient of 0.9 and an
average temperature of at least 800 °C, fully engulfing the specimen, with a surface
absorptivity coefficient of 0.8 or that value which the package may be demonstrated to possess
if exposed to the fire specified, followed by;
(b) Exposure of the specimen to an ambient temperature of 38 °C, subject to the solar insolation
conditions specified in Table 6.4.8.6 and subject to the design maximum rate of internal heat
generation within the package by the radioactive contents for a sufficient period to ensure that
temperatures in the specimen are everywhere decreasing and/or are approaching initial steady
state conditions. Alternatively, any of these parameters are allowed to have different values
following cessation of heating, providing due account is taken of them in the subsequent
assessment of package response.
During and following the test the specimen shall not be artificially cooled and any combustion of
materials of the specimen shall be permitted to proceed naturally.

 

Water immersion test: The specimen shall be immersed under a head of water of at least 15 m for a
period of not less than eight hours in the attitude which will lead to maximum damage. For
demonstration purposes, an external gauge pressure of at least 150 kPa shall be considered to meet
these conditions.
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