Since the unfortunate September 11 event, air safety has tightened its requirements for liquids, gels and aerosols aboard an aircraft.
The rules are as follows:
Liquids, aerosol set gels are accepted at pre-board screening checkpoints if they are in 100 ml/100 g (3.4 oz) containers and less.
All containers must be placed in a single transparent plastic bag with a closing
The bag can have a maximum capacity of one (1) litre (one pint)