Some liquids are highly volatile and can have low combustion thresholds and can’t be taken onto planes because there is a risk of them exploding or catching fire harming people and property. It is not safe to take them on the plane – they're 'restricted from carriage'.

Avsec x-rays bags going on planes to make sure there is nothing dangerous in them. If something comes up on the x-ray that needs checking, the bag will be opened and searched.

Most flammable liquids are strictly forbidden. Refer to this table for more information:

Flammable liquids

Lighter fluid


Carry-on bag

Check-in bag 

 Flammable Liquid 1

All lighter refills and fluid containing highly flammable butane, hydrocarbon mix, or petroleum distillates must not be taken on the plane.

Valve oil


 Flammable Liquid 2

Valve oil containing petroleum distillates or hydrocarbons must not be taken on the plane.

70% alcohol by volume


 flammable Liquid 3

Alcohol that exceeds 70% alcohol by volume must not be taken on a plane. Alcohol used for cleaning (e.g. isopropyl) or "rubbing" alcohol will likely exceed the 70% limit. Alcohol purchased from a duty free store is likely to be okay. 

Engine fuel


flammable Liquid 4

Ask your airline if you want to take combustion engines. The engine must not contain any free liquid. If the engine has not been cleaned and all free liquids removed, leave it at home, as it is unlikely to be allowed to travel.

Preserved specimens

 Flammable Liquid 5 Ask your airline if you intend to travel with biological specimens that have been preserved in alcohol. You will need to find out about their packaging requirements.

Hydraulic oils

 Shock Absorber Hydraulic Oils

Shock absorbers, including gas struts, are not permitted onto passenger aircraft.

You should contact a Regulated Air Cargo Agent to discuss how you transport them on a cargo aircraft.

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