Some items contain hazardous chemicals and can’t be taken onto planes because there are risks with them exploding or catching fire harming people and property. It’s 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.
The carriage of some hazardous chemicals such as liquid oxygen is strictly forbidden. Contact your airline if you are carrying any items that contain hazardous chemicals that are not covered in the following table:
Items with hazardous chemicals
| Item Type | Restrictions | Carry-on Bag | Check-in Bag |
|---|---|---|---|
|
Mercury
 |
Barometers contain mercury and must not be taken on a plane. |
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|
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Travelling with a Medical Thermometer? They contain small amounts of mercury and must be carried in a protective case in your check-in baggage.
|
|
 |
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Energy efficient light bulbs contain small amounts of mercury. You can take them on the plane, but only if they are in their retail packaging. |
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Carbon Dioxide
 |
Carrying dry-ice packaging? Only use containers that have been manufactured for that purpose, as the package must be vented to release carbon dioxide. There is a limit of 2.5kg of dry-ice per passenger. |
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Liquid Nitrogen
 |
Travelling with a dry-shipper? Only use dry-shippers that have been manufactured for that purpose, as they have been designed to prevent build-up of pressure and the release of liquid nitrogen. |
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Some Government employees are required to travel with specialised equipment that contains hazardous chemicals. If this applies to you please contact your airline before you travel as their approval will be required and in most cases the pilot is required to be informed.