The DOT has rules for how cylinders should be secured inside vehicles. It is important to follow these rules in order to avoid penalties, fines, and most importantly injuries.

How Cylinders Should Be Secured Inside Vehicles

Cylinders need to be secured in racks to prevent moving, shifting or ejecting during normal transportation. (49 CFR 177.840)
 

• For closed vehicles this means that the cylinders must be secured for minimal movement in the forward, backward or lateral direction (49 CFR 393.102)

• For open vehicles, they must also be secured for upward movement (49 CFR 393.102), secured by something that gives it 20% downward force (49 CFR 393.102)