Please do not print on the plane

| Comments (1) | Security: Airport
Flying With Fish reports that the TSA will be restricting toner cartridges (þ Matthew Kaufman):
This coming Monday, the 8th of November, the Transportation Security Administration (TSA) expects to announce that it will prohibit airline passengers from flying with printer ink and toner cartridges, sized at 16oz by volume or larger. This will be Security Directive (SD) 1554-10-05.

As of this evening, the TSA appears to be working on the exact wording of prohibiting these items, however prohibiting printer cartridges poses a few challenges ... mainly that generally printer cartridges do not have their ink or toner volume readily listed on the cartridge its self.

This feels like classic fighting the last war. As far as I can tell there's not much special about printer cartridges. Here's FWF's source:

Now that the global security community is aware of printer cartridges as a potential way to conceal explosives anyone seeking to stay out of the line of sight of security forces will move onto a new item to conceal their weapons. If I was on the front line of aviation security I would suggest seriously looking at desktop hard drives, portable DVD players or home video game consoles. These are all items with enough internal space to pack an explosive in addition to providing the ability to camouflage the trigger wiring harness. Under normal circumstances these items may not catch a second glance, but you have to wonder what kind of person checks a desktop hard drive, portable DVD player or home video game console given the likelihood of damage or theft.

Moreover, if you're going to carry the bomb in carry-on, there's no requirement that the explosive and the triggering mechanism even be in the same package, since you can assemble them in place. All you need is the ability to pack the explosives into something that will pass the x-ray machine (or alternately you can probably walk them through the magnetometer; ever see a "wine rack"?) and then some other place to conceal the triggering mechanism. It seems like it shouldn't be too hard to make it look like some other piece of consumer electronics. Note that since you can separate the trigger mechanism from the explosive, you can have two different people bring them through security, thus arousing even less suspicion (and potentially bearing more scrutiny if you get secondary screening).

It's possible, of course, that for some reason printer toner is really hard to distinguish from explosives using the kind of detection apparatus we have available. In that case, it might possibly make sense to restrict toner (whether in cartridge form or not). However, printer toner is a carbon/plastic compound, so it seems like it would probably show up a lot like any other kind of plastic under X-ray, nitrogen scanning, etc. Even if toner is hard to distinguish from explosives, it doesn't make much sense to restrict it unless it's somehow uniquely hard to distinguish.

Assuming this report is correct, it will be interesting to see what rationale TSA provides.


A toner cartridge contains both some kind of homogenous chemical preparation and some electronics - as such it's a better camouflage for a bomb than a DVD player - the explosives will look on X-ray like something that fundamentally shouldn't be in a DVD player or any other normal electronic device, whereas in a toner cartridge they can look like toner.

Assembling a bomb on a plane requires a technician who is also a suicide bomber - there are good reasons for separating those two roles.

Leave a comment