Container access control

A security box for securing a container, comprising:

• a back portion comprising sidewalls having openings, a back wall, and at least one blocking flange, the back portion generally shaped as a box open on one face opposite the back wall;
• a front portion comprising a front wall, a shaft passing through the front wall, and sidewalls having openings, the front portion generally shaped as a box open on one face opposite the front wall;
• a hinge connecting the back wall of the back portion to the front wall of the front portion;
• the openings in the sidewalls of the back portion and the openings in the sidewalls of the front portion being positioned such that when the front portion is swung about the hinge towards the back portion to place the security box in a closed configuration, a generally closed box is formed but with openings at the sides, all openings being sized to accommodate a handle of a lockrod assembly of a container door;
• a lock within the front portion preventing the shaft from rotating when in a locked configuration;
• and
• a blockable member attached to the shaft and which is rotatable parallel to the front wall of the front portion, and rotatable so as to be placed between the at least one blocking flange and the back wall when the shaft is rotated and the security box is in the closed configuration.