Never allow a person to ride in the trunk:
Allowing a person to ride in the trunk is dangerous. The person in the trunk could be seriously injured or killed during sudden braking or a collision.
Do not drive with the trunk lid open:
Exhaust gas in the cabin of a vehicle is dangerous. An open trunk lid in a moving vehicle will cause exhaust gas to be drawn into the cabin. This gas contains CO (carbon monoxide), which is colorless, odorless, and highly poisonous, and it can cause loss of consciousness and death. Moreover, an open trunk lid could cause occupants to fall out in an accident.
Before opening the trunk lid, remove any snow and ice accumulation on it. Otherwise, the trunk lid could close under the weight of the snow and ice resulting in injury.
Be careful when opening/closing the trunk lid during strong winds. If a strong gust blows against the trunk lid, it could close suddenly resulting in injury.
Fully open the trunk lid and make sure that it stays open. If the trunk lid is only opened partially, it could slam shut by vibration or wind gusts resulting in injury.
When loading or unloading luggage in the trunk, turn off the engine. Otherwise, you could get burned by the heat of the exhaust gas.