In a real time container monitoring system, a data collection computer is in communication with the control computer of a container crane. The electrical signal from each of the radiation detection units carried by the spreader of the container crane is applied to the data collection computer to store as digital data information commensurate with the electrical signal from each of the radiation detection units in response to the control signal being indicative that the container has been engaged by the twist locks. A data analysis computer is in network communication with the data collection computer to download the digital data from the data collection computer and analyze the digital data to determine whether the threat material is present in the container.