roberino

I am flying from MAN this evening and saw a small printed notice just after the metal detectors in security screening. It said something along the lines of:

"Do not use Gojo with blue latex gloves as the combination can result in false positives." (High possibility I have misquoted as I couldn't take a photo, it's late and I have a shockingly bad memory).

I can only only assume that this means that using some sort of hand steriliser (speculation) with the gloves causes false positives in the explosives screening instruments. Does anyone have more info on this?

And how safe are we really if latex gloves are triggering alerts at security?

Kagehitokiri

https://www.gojo.com/

i recall an FTer had gloves cause a false positive

747FC

You are very safe with false positives. You are not safe with false negatives.

GUWonder

Some hand lotions and sanitizers have components with particulates that cause a "true positive" match during screening but are harmless to the flight in the quantity and distribution they are had by a given passenger.

That is anything but entirely and necessarily true, unless taking it that "we are very safe" with or without the dog and pony show of security theater.

Encountering too many "false positives" may generate complacency that ends up being a distraction that enables smuggling of contraband WEIs. [Think about the boy who cried wolf.]

Most "true positives" at screening checkpoints are taking place when there is no contraband WEI to be seized by the screeners. Just because a true positive match for certain molecules takes place does not mean there is necessarily a contraband WEI present to be seized/interdicted. That is why some say that "false negatives" are generally not as dangerous as the knee-jerk crowd believes the "false negatives" to be.

ETD means at airports are useful more for their deterrence impact than for effectively detecting and interdicting all possible contraband explosive means/devices that could seriously injure or kill people on planes.

KRSW

Does anyone know what the explosives detectors pick up on? I know nitrogen is at least one of the compounds being looked for -- my friend's wheelchair got the smurfs in a frenzy. Appears he rolled through recently-fertilized grass on his way to the airport.

Ocn Vw 1K

Please follow the thread as it moves to the apt travel security forum. Ocn Vw 1K, Moderator, TravelBuzz.

747FC

Your polemics do not negate the truth that one instance of a false positive as the OP experienced does not entail any security risk. A false negative presents a considerable one.

SeriouslyLost

Most of the machines are simply looking for a ratio of nitrates and phosphates above certain background limits. They're not really terribly complicated machines. The complexity comes in with having them test quickly, consistently, and making the protein sack users run them correctly.

And talking of using them correctly, the TSA drone at DCA this morning was using a single swab to run across groups of 5+ people at a time "because the line was busy". Adding to the hilarity, in between groups she was running her hands through her hair (to keep it from her eyes) which obviously had styling product in it. She gave me a really dirty look when I said to the group (none of whom knew each other) as she swabbed us that if it came back positive we should all point at the 5 year old in the group.

GUWonder

Some kinds of fertilizers indeed will have particulate matter that will set off some types of ETDs.

[The air I breathe usually has way more nitrogen than oxygen.]

Polemics? No. I'm talking about the practice of encountering too many "false positives" having a history of generating complacency that ends up being a distraction that enables smuggling of contraband WEIs. [Think about the boy who cried wolf.]

If you have proof that contradicts the following:

then you should consider supplying the TSA with that (i.e. "the false negatives present a considerable risk" to flight security), as the TSA loves examples in an effort to try to justify their expenditures in the name of security. If you know how the various tools used for ETD actually work, then you realize that "false negatives" take place rather routinely. Sensitivity levels, my dear.

False positives for "explosives" do increase risk of security failures, as personnel performance is not static in the face of false positives.

seadog83

By far the best example of this is liquids. Going through security you see a great big garbage bin filled with fluids tossed away. Under the guise that they are potential explosives.

Now what would happen if someone tried to bring *actual* liquid explosives through in a water bottle? They would get tossed in the bin with the rest, and no one would give it a second look.

So now you have a situation where either we have to treat every single liquid filled bottle (the vast majority of which are harmless) as a live explosive (shut down airport, evacuate, bring in bomb squad, etc) or treat every single liquid filled bottle, as well a water filler bottle. The former wastes huge amounts of resources, the latter completely discounts the threat of actual explosives.

jmmtn4aj

As mentioned earlier, our air is mostly nitrogen, so yeah I don't think that alone triggers anything.

Instead it detects compounds, or mixtures of otherwise common elements that should not appear in specific proportions. The warning about Gojo and latex gloves is probably because latex and petroleum (distillates of which are present in Gojo) are the primary ingredients for napalm.

Loren Pechtel

Yup. Ammonium nitrate is used as fertilizer--and it's also an explosive, albeit quite hard to detonate.

Kagehitokiri

on top of bureaucratic complacency, which is not the fault of entry level staff

cbn42

It would be very difficult to bring a spontaneously explosive liquid up to the checkpoint. The concern with liquids on planes is that they can be used to make explosives on board. This would require mixing them in a certain way, injecting them into a pressurized container with a syringe, and having some sort of flame to detonate. Most potentially explosive liquids that are tossed into the bin with the others are completely harmless sitting there until discarded.

gqZJzU4vusf0Z2,$d7

GoJo is essentially jellied mineral spirits - petroleum.