Tamper evident

Indicators and barriers

On this page13

The definition A barrier stops entry An indicator shows entry The definition accepts either And the test is the same for both Missing is the half people forget Which is the argument for a printed seal Visible evidence to consumers So the feature has to be noticeable as well as present A barrier that reseals is neither So the liner field has to be read for function, not presence Our shelf has barriers and no indicators References

One or more indicators or barriers to entry. The distinction is worth having.

The definition

A tamper-evident package is one having one or more indicators or barriers to entry which, if breached or missing, can reasonably be expected to provide visible evidence to consumers that tampering has occurred.

A barrier stops entry

A foil seal across the mouth, a sealed inner wrap, a bonded closure. Something that has to be destroyed to get in.

An indicator shows entry

Which does not have to resist anything. A band that cannot be replaced, a ring that breaks, a mark that changes.

The definition accepts either

One or more indicators OR barriers to entry. So a package can be tamper-evident without being hard to open.

And the test is the same for both

If breached or missing, can reasonably be expected to provide visible evidence to consumers that tampering has occurred.

Missing is the half people forget

A feature that can simply be removed without trace fails, which is why the clause names breached and missing together.

Which is the argument for a printed seal

A blank foil seal that has been removed can be replaced with another blank foil seal. A printed one cannot, unless the printing is available too.

Visible evidence to consumers

Not to an inspector and not under a lamp. The audience named is the person buying it.

So the feature has to be noticeable as well as present

Which is why the statement in paragraph (c) exists: a consumer has to know what to look for before they can notice it is gone.

A barrier that reseals is neither

Which is the trap on this shelf. 39 of the 128 closures carry a liner that reseals on closing, and a liner that reseals leaves no evidence.

So the liner field has to be read for function, not presence

Heat induction seal and pressure sensitive show interference. F217, foam and PE foam are sealing liners that do not.

Our shelf has barriers and no indicators

53 heat induction seals and 18 pressure sensitive liners, which are barriers. No shrink band, no breakaway ring and no tamper-evident closure among the 128.

References

21 CFR 211.132(b)(1): "A tamper-evident package is one having one or more indicators or barriers to entry which, if breached or missing, can reasonably be expected to provide visible evidence to consumers that tampering has occurred." The same paragraph requires the packaging to be "distinctive by design or by the use of one or more indicators or barriers to entry that employ an identifying characteristic (e.g., a pattern, name, registered trademark, logo, or picture)", with distinctive by design meaning packaging that "cannot be duplicated with commonly available materials or through commonly available processes." The section reaches an over-the-counter human drug product packaged for retail sale and accessible to the public while held for sale, and nothing here asserts it binds any particular activity. law.cornell.edu

The Davis Pack Supply catalog, measured 19 October 2026. The only tamper-evident capability among the 128 closures indexed to this group is a liner: 53 carry a heat induction seal and 18 a pressure sensitive liner, with 11 F217, 11 foam, 10 Plastis standard, 6 PE foam, 1 F217 and PS, 8 recorded as No Liner and 10 unrecorded. There is no tamper-evident closure and no sealing disc on the shelf at all. We publish the liner type and not whether it carries a printed pattern, name, trademark, logo or picture.

Written from 21 CFR 211.132 and from the catalog as it stood on 19 October 2026. That section reaches an over-the-counter human drug product packaged for retail sale and accessible to the public while held for sale; a kit assembled at home from bulk is not that, and nothing here asserts the section binds any particular activity. The only tamper-evident capability on this shelf is a liner, and we publish the liner type and not whether it carries a printed identifying characteristic, which is the attribute the distinctiveness requirement turns on.