Short answer: 3.4 oz. For more details, read on…
When TSA lifted the total liquid ban and implemented the 3-1-1 program, the permissible amount of liquids, aerosols and gels was 3oz. Press releases went out, WebPages were updated, and signs were printed and shipped out nationwide to 457 airports.
When TSA rolled out 3-1-1, the European Union was not on board yet. When the EU decided to lift the ban and allow liquids to travel, the amount permitted was 100ml. Well, as those of you who like me had to learn metric conversion in grade school, youmight remember that 100ml = 3.4oz. not 3 oz. In order to align with the EU, we decided to allow liquids in containers up to 3.4oz. We also decided to keep our signage the same to maintain consistency. (Besides, 3.4-1-1 just doesn’t have the same ring to it.)
We’ve read your concerns here on the blog, so from now on, we’ll use 3.4 on the blog when talking about liquid limits, and also make changes (as soon as possible) to the TSA web site. I worked with Lynn on this and she has crafted a new response for the contact center to use when communicating with the public. We are also going to send a message to the workforce as a reminder.
Some people have asked why we don’t convert the net weight of the toothpaste to volume since they are different. Good question. The 3.4 container/volume rule was created to make it simple and streamlined for both passengers and our officers. As you could imagine, taking weight into consideration would be a wrench in the spokes. I’m sure the public doesn’t want our officers using scales or conversion charts, etc.
I hope this has helped you better understand the 3.0/3.4 oz. conundrum.
EoS Blog Team