The Shanghai Metro does not allow the use of two-way radios. So, you don't need to worry about that.
Items prohibited on Shanghai Metro include, but are not limited to:
1. Live poultry and pets such as cats and dogs (excluding guide dogs).
2. Bicycles (including folding bicycles).
3. Flammable, explosive, toxic, radioactive, corrosive, and other items that pose a danger to human life and property safety.
4. Items with a strong odor, fragile, sharp objects that have not been properly packaged for safety.
Note: The weight of items carried by passengers must not exceed 23 kilograms, the volume must not exceed 0.2 cubic meters, and the length must not exceed 1.7 meters. Items should also not obstruct other passengers' travel.
The following provides detailed information.
Limited carry of dangerous items related to daily life.
(1) Each passenger is limited to carrying a maximum of two items: matches, inflatable can, nail polish, mousse container, and perfume spray.
(2) Each passenger is limited to carrying no more than 1 liter (1 kg) of high-proof white liquor, and the packaging must be intact.
Examples of classifying dangerous goods:
(1)Explosives
For example: explosives, fireworks, firecrackers, rockets, firearms (including realistic replicas), ammunition, and detonators.
(2)Compressed gas and liquefied gas
For example, including carbon monoxide, propane, refrigerants like HFCs, hydrogen, oxygen, liquefied petroleum gas (LPG), natural gas, and various compressed gases.
(3)Flammable liquid
For example: gasoline, diesel, alcohol (ethanol), acetone, propane, paints, benzene, methanol, solvent oils, turpentine, banana oil, kerosene, and plastic printing inks.
(4)Flammable solids, self-igniting materials, and moisture-sensitive flammable materials
For example: phosphorus, sodium, sulfuric acid, potassium, aluminum powder, zinc powder, etc.
(5)Oxidizing agents and organic peroxides
For example: sodium nitrite, sodium nitrate, potassium chlorate, etc.
(6)Toxic substances and infectious materials
For example: cyanide, arsenic salts, organophosphorus pesticides, mercury compounds, etc.
(7)Radioactive materials
For example: night glow powder, solitary stone, hao-ying stone, etc.
(8)Corrosive substances
For example: hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, etc.
(9)Other hazardous items
For example, items that could endanger passenger safety and affect the security of subway facilities, such as balloons, shovels, long poles, saws, iron bars, and prohibited weapons.