Hair gel is dangerous because it contains flammable substances in addition to strong pressure. When the plane flies at high altitude, the pressure in the cargo hold is uneven, which may easily lead to the explosion of compressed gas cylinders and cause flight safety hazards. Therefore, it is generally not allowed to carry it on the plane or check it in.

Article 36 of the China Civil Aviation Passenger Baggage Transport Rules stipulates:

The carrier shall be liable for the loss or damage of the above items carried in the checked baggage according to the ordinary checked baggage. Prohibited articles, restricted transport articles, dangerous goods, and other articles with peculiar smell or easily polluting aircraft as stipulated by the state shall not be checked as baggage or sandwiched in luggage.

Extended data:

Styling spray is a flammable liquid containing alcohol. According to the regulations of the Civil Aviation Administration, inflammable, explosive and corrosive articles cannot be checked, and flammable dangerous goods are marked on the modeling spray.

Generally speaking, inflammable, explosive, toxic, radioactive and corrosive articles are not allowed, nor are guns and controlled knives allowed.

There are also some luggage that is forbidden to be checked, including some fragile or perishable items; Precious jewelry, metals, gold and silver, antique calligraphy and painting and other items; Important documents, personal certificates, certificates, etc.