More than eight years after restrictions were imposed on hand luggage, some travellers are still confused about what they can and cannot carry on board a plane.
About 1.2 million liquid, gel and aerosol items - including hair spray and toothpaste - were confiscated from travellers at Changi Airport between January and November last year.
The number of confiscated items, though, has come down.
The figure for last year translates into 4.85 items per 100 departing passengers, compared with 6.45 items in 2009, Changi Airport Group told The Straits Times.
About three in 10 confiscated items are water in disposable bottles. Personal items like hair spray, gels and toothpaste, as well as food products like kaya and canned food, for example, have also been surrendered.
What you can and cannot carry in hand luggage
Q What are the rules on liquids, gels and aerosols in hand luggage?
A Items must be in containers with a maximum capacity of 100ml each.
All containers (not exceeding one litre in total) must be placed in a transparent re-sealable plastic bag which must be completely closed.
Q Can I carry a container larger than 100ml but partially filled?
A No, the maximum capacity for the container is 100ml.
Q What about foams and semi-solids like honey and jams?
A The same rules apply for foams and semi-solids. Exemptions can be made for baby food if the infant is also travelling. The same applies to medicines if you have an original letter from a certified medical practitioner.
Q Are there guidelines on items such as tweezers, nail clippers, penknives, Swiss Army knives, screwdrivers, scissors and toys or ornaments that look like guns?
A These items should be checked in.
Changi Airport introduced the guidelines in May 2007, as recommended by the International Civil Aviation Organisation, a United Nations agency which oversees global commercial aviation.
This was after police in Britain foiled an apparent plot to blow up as many as 10 transatlantic flights with liquid explosives on Aug 10, 2006.
Public education on items allowed on board flights is ongoing, Changi Airport's spokesman Ivan Tan said.
"We encourage travellers to check the guidelines on the Changi Airport website before they travel, to avoid the inconvenience of having to discard belongings or purchases. At the airport, there are visual displays at the check-in counters to remind travellers to check in items if these exceed the permitted limits."
There are also display cases in the departure halls, which contain life-size samples of items showing which should be checked in, as well as those which cannot be taken on board aircraft cabins, he said.
For safety and hygiene reasons, confiscated items are discarded unless travellers want to mail them.
The rate for local delivery, as part of a service provided by the airport in partnership with Singapore Post, is $10 for items weighing up to 2kg. Charges vary for overseas delivery.
About 2,400 items on average are mailed a year.
Church administrator Bertilla Watanabe, 55, who had wanted to take home a bottle of Ya Kun kaya after a three-week holiday in Singapore last Christmas, said: "I thought kaya was okay; I was really looking forward to taking some good kaya home to Vancouver.
"But the security guy just said, 'Sorry, kaya cannot. It's a security risk.' I didn't say anything, as I didn't want to quibble over a bottle of kaya. But I was so sad they took my kaya away."