Guidance material on ICAO Standards and Recommended Practices
Volume IV. Preventive Security Measures Doc 8973/7
poor throughput of the security screening process, even with very good detection rate, might generate
additional queues, which could easily be targeted by perpetrators for attacks inside the terminal building,
including suicide attacks, even before the first screening point.
Finally, potential negative side effects have to be considered on the training, certification and evaluation of
the performance of the screening staff if equipments are too complicated to operate and if the list of items to
be detected is too large or too diverse.
Priorities in Dangerous Items Lists
It is therefore essential to develop the following breakdown on the Dangerous Items Lists for better overall
performance
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of security systems:
1) Priority 1: all potential Dangerous Items, devices or elements of devices which may be placed
inside an aircraft using passengers, cabin baggage, hold baggage, cargo, catering, stores or
supplies and other goods and which could potentially be used to commit a major act against civil
aviation security. Are included:
a) all items of category I at any quantity for passengers, cabin baggage; and
b) all items of categories II and III in quantities
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susceptible of compromising the survivability
of an aircraft in flight for passengers, cabin baggage, hold baggage and cargo.
2) Priority 2: all potential Dangerous Items, devices or elements of devices which might be left in
Security Restricted Area, including aircraft and make-up area by staff as such items could used by
passengers, including potential perpetrators travelling at a later stage. However, this list is a priority
2 as all staff are normally subjected to background checks, initial and continuous training, and could
be educated to avoid any interference of disruption. Are included:
a) All items of category I at any quantity;
b) all items of categories II and III in quantities
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susceptible of compromising the survivability
of an aircraft in flight for passengers, cabin baggage, hold baggage and cargo; and
c) all items of categories II and III in quantities
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susceptible of damaging aircraft or
installations, or be used to kill/injure a large number of persons at terminal buildings.
3) Limitations and bans: all items listed in Priority 1 and Priority 2 which are in quantities, or number,
not detectable or identifiable by contemporary screening equipment and systems
The limitations or bans are essential additional preventive measures for security controls purposes to limit
the carry-on of potentially Dangerous Items in quantities that are not (yet) detectable or identifiable by
contemporary screening technologies and systems. These limitations, or bans, currently focus on liquids,
gels, creams and aerosols which could hide liquid explosives or substances inside apparently innocent
containers and bottles with the intention of committing an act of unlawful interference inside the aircraft or
airport facilities.
The same type of limitations or bans could technically apply for chemical and toxic substances being
transported via aircraft with the objective of dissemination during the flight, or in different States in a very
short period of time. However, the efficacy of counter measures implemented at airports only for such threat
is very questionable and States are encouraged to develop plans and coordination at national and
international levels to strengthen their intelligence and counter terrorism abilities to deter such acts at the
preparation stage
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.
Moreover, the limitations, or bans, on items which could contained Dangerous Items are only designed to
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including technical and performance evaluation of detection equipment
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Quantities are determined by the appropriate authorities. These figures also serve for detection performance purposes
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normally the same quantities as for Priority 1
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Quantities which might be higher.
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See Volume I – Intelligence and Counter terrorism part
Volume IV - 5
DRA06
DGP-WG/06-WP/50
Appendix A