The <a href="https://justtravo.com/blog/tsa-liquid-limit-carry-on-liquid-size/">3-1-1 liquids</a> rule, created by the Transportation Security Administration (TSA) in the US, is a set of guidelines for carrying liquids in carry-on luggage for air travel. According to this regulation, travellers are allowed to bring a quart-sized bag of liquids in their carry-on luggage, including aerosols, gels, lotions, and pastes. Each item must be contained in a container weighing 3.4 ounces (100 millilitres) or less, and the bag must be removed from the luggage before going through security. Containers weighing more than 3.4 ounces must be checked in as luggage or left at home and are not permitted in carry-on bags. The 3-1-1 regulation limits the quantity of potentially hazardous liquids that can be transported onboard in an effort to promote aviation safety.