closures which may not be detected by visual examination. Normal appearing cans
should be shaken vigorously to detect leakers (see paragraph 2-12d), and the ends
should be struck against a flat surface to detect flippers (see paragraph 2-10b). The
containers must be examined under proper illumination in order that visual defects can
be easily detected. Examine each container carefully. Refer to inspection aids, as
applicable, to properly classify each type of defect.
There are three classifications for container defects.
a. Critical. A critical defect may result in hazardous or unsafe conditions for
individuals using the product.
b. Major. A major defect materially reduces the usability of the unit of product
for its intended purpose or has the potential to develop into a critical defect.
c. Minor. A minor defect may or may not limit serviceability due to appearance,
but it does deviate from the contract and/or specification.
a. Dents. The most prevalent defect discovered during closed-packed
inspection is the dent. This is a permanent distortion of the can due to external forces.
Dents do not render the product in the container unserviceable or cause the product to
present a health hazard. Can dents are judged according to severity and to location
and are generally limited to three types: irregularity, moderate dent, and severe dent.
Cans containing more than one dent are classified on the basis of the most serious
dent. There are no critical defects for dents.
(1) Irregularity. An irregularity is a flaw that does not limit serviceability and
is too slight to be considered a minor defect. Irregularities are not listed in the
specifications or inspection reports. Irregularities are indentations with small or well-
rounded commissures. (A commissure is the place where two bodies or parts unite. It
is the junction of the ridges of the dent.) An irregularity has no clearly defined apexes.
(An apex is a narrow or pointed end.) An irregularity has no sharp ridges or points
present. When an irregularity involves a seam, the malposition can only be detected by
(2) Moderate dent. A moderate dent is a defect that limits the item's
serviceability (including appearance), only slightly or not at all. Nevertheless, this
constitutes a deviation from the specification or contract requirements. Moderate dents
are classified as minor defects. A moderate dent has moderately deep or sharply
rounded commissures and moderately acute apexes. A moderate dent of the end seam
will have the seam forced inward but will not involve the countersink and no sharp