Barrier seals come in almost as many varieties as barriers themselves do: there are barrier seals for large storage trailers all the way down to small corrugated boxes. Some will completely bar entry while others will deter entry by exposing any break-in. There is even a seal that looks like it can be resealed, but reveals a hidden message after the seal has been broken, exposing the crime later.

The Uses of Barrier Seals

In the shipping industry, everything from individual boxes to the large containers that hold them need to be secured, as well as the trucks that haul the containers from location to location. Making barriers impregnable is, of course, a high concern, but making breached barriers apparent is another goal. Getting into the mind of a thief will make this easier to understand.

Thieves that continually "skim off the top" by pilfering regularly get away with it, generally, because no one knows when and where the crime is happening. When tens of thousands of parcels go through a distribution center a day--many of them hundreds of miles away from their point of departure and final destination--any one can easily help himself to merchandise. The crime won't be noticed for hours or even days, and it's too hard to track down where the skimming is taking place.

Thieves don't want to upset this system by pointing out where the theft is occurring. Tamper evident barrier seals do just that: they make it plain as day that foul play has happened, jeopardizing the thief's racket. If a simple visual inspection will indicate how a thief broke into a container or a parcel, he'll stop or find an easier target.