How aviation security rules changed: a dated timeline from 1974 to 2025

Timeline at a glance

The table lists key events and the rule changes that followed. Dates are as given in the sources.

1974: Annex 17 sets the global baseline

Annex 17 to the Chicago Convention holds the international standards for aviation security. Its first edition dates from March 1974. The Twelfth Edition, Amendment 18, applies from 18 November 2022 and holds 95 standards and 21 recommended practices ¹.

Annex 17 requires states to screen departing passengers and their cabin bags before boarding, with methods able to detect explosives. Originating hold bags must be screened before loading ¹. Airlines may carry the bag of a person who is not on board only if it is identified as unaccompanied and screened ¹.

1988: Lockerbie

On 21 December 1988 Pan Am Flight 103 left London Heathrow for New York. It exploded over Lockerbie, Scotland, killing all 259 people on board and 11 people on the ground, according to the FBI. Investigators found the bomb had been placed inside a radio in a piece of luggage ².

The attack showed the danger of a bomb in the hold. Today's Annex 17 rules on hold bag screening and on matching bags to passengers address that threat directly ¹. The sources reviewed for this page do not give a dated list of the rule changes made in direct response to Lockerbie.

2001: 9/11 and the creation of the TSA

After the attacks of 11 September 2001, the US Congress passed the Aviation and Transportation Security Act, approved on 19 November 2001. It created the Transportation Security Administration as part of the Department of Transportation ³.

The Act required screening of all passengers and property carried on passenger aircraft. For flights from US airports, screening had to be done by federal government employees, with listed exceptions. The Act set a deadline of 31 December 2002 for screening all checked bags with explosive detection systems ³.

2006: the liquids plot and the 100 ml rule

The European Commission says it adopted its liquids rules after attempts to blow up several aircraft departing London Heathrow with homemade explosives in 2006. The rules limit liquids to containers of no more than 100 ml, packed in one transparent re-sealable bag of one litre, with exemptions for medicines, special diets and baby food ⁴.

The legal act was Commission Regulation (EC) No 1546/2006 of 4 October 2006, published on 17 October 2006. It cited the increased risk of liquid explosives and said the measures should be reviewed every six months. Its detailed annex was kept secret, with a duty to inform passengers about prohibited items ⁵.

2009 and 2010: the underwear bomb and the cargo plot

The European Commission says the attempted attack of 25 December 2009 on a Northwest Airlines flight, with explosives hidden on a passenger, showed that traditional checkpoint equipment was not fully effective. A Commission communication in June 2010 confirmed security scanners as a valid screening method. In November 2011 the Commission adopted an EU legal framework for scanners ⁶.

In the UK, the government announced on 5 January 2010 more explosive trace detection, more random searches and the introduction of security scanners. On 1 February 2010 it announced scanners at Heathrow and Manchester ⁷.

On 29 October 2010, two suspicious packages from Yemen were found in the UK and the United Arab Emirates. Canada responded on 8 November 2010. It banned printer and toner cartridges of 500 g or more from checked bags on flights from Canada and from cabin bags on flights to the US. It banned all cargo and mail from or through Yemen and Somalia ⁸.

2016 and 2017: UN resolutions and laptop restrictions

On 22 September 2016 the UN Security Council unanimously adopted resolution 2309 on aviation security. It called on states to make sure effective, risk-based measures are in place at their airports and to strengthen screening and the use of new detection technology ⁹.

In March 2017 the US Department of Homeland Security banned electronic devices larger than a smartphone from cabins on direct flights to the US from 10 airports in eight countries in the Middle East and North Africa. DHS said on 19 July 2017 that all those restrictions had been lifted, with enhanced security measures in place ¹⁰.

On 21 December 2017 the Security Council adopted resolution 2396 ¹². It decided that states shall require airlines to provide advance passenger information (API), develop the capability to use passenger name record (PNR) data, build watch lists of known and suspected terrorists and develop biometric systems, in line with human rights law ¹¹.

2022 to 2025: CT scanners and changing liquids rules

On 15 December 2022 the UK government said cabin bag limits would not be lifted until June 2024. Major airports would have to install new screening equipment such as CT scanners. Passengers would then be able to carry containers of up to two litres ¹³.

The rollout did not go smoothly. From 9 June 2024 the 100 ml limit returned temporarily at six regional UK airports that had new checkpoints in full operation ¹⁴. From 1 September 2024 the EU restored the 100 ml limit at airports using explosive detection systems for cabin baggage. The Commission called it a precaution over a temporary technical issue ¹⁵.

In 2025 some airports moved ahead again. Dublin Airport let passengers carry up to 2 litres from 17 September 2025, after installing about 30 new cabin bag scanners and body scanners. It said it finished the switch ahead of a regulatory deadline of 31 December 2025 ¹⁷. In the United States, DHS Secretary Kristi Noem said on 8 July 2025 that TSA would no longer require travellers to remove their shoes. The shoe rule dated from 2006 ¹⁶.