Efforts are under way in various States to develop and deploy new screening technology at airports capable of detecting hazardous substances within liquids, aerosols and gels (LAGs).
In the meantime, the threat posed by LAGs has been addressed by issuing security control guidelines for carry-on LAGs, including specifications for secure tamper-evident bags suitable for in-flight and airport purchases.
 
The volumetric controls that currently apply to LAGs were developed and disseminated by ICAO following the unveiling in 2006 of a terrorist plot to sabotage aircraft in-flight by assembling an improvised explosive device using hazardous ingredients carried in seemingly ordinary LAGs.
 
In October 2008, States were provided with guidance material to help ensure that the security control guidelines for LAGs are implemented in a harmonized manner worldwide.
 
Security tamper-evident bags (STEBs) were developed to allow an exemption to volumetric controls for liquids purchased at airport retailers or on board aircraft and carried by transfer passengers. Details concerning their production, of particular interest to potential suppliers, are available on the linked pages.
 
At its meeting in March 2010, the ICAO Aviation Security Panel concluded that the threat from liquid explosives remains a concern. The Panel recommended that the ICAO Secretariat Study Group on the Carriage and Screening of Liquids, Aerosols and Gels develop guidance for States on the implementation of technological solutions for the screening of LAGs. The deployment of such solutions would allow for the gradual removal of the current restrictions on carry-on LAGs.