APM Terminals Callao
The Challenge
At APM Terminals Callao, container tallying requires personnel to stand on the steps of a semitrailer, either at the rear or on the side. This position places workers in a vulnerable zone where any unexpected movement of the Terminal Truck (TT) could lead to a fall, a strike incident or a serious crush injury. Even a momentary, unintentional gear engagement by the operator is enough to create a life threatening situation.
The core challenge was to guarantee complete immobilization of the TT during tallying—removing the possibility of accidental movement and protecting workers who must operate in extremely proximity to heavy equipment.
The Innovation
To eliminate this risk, APM Terminals Callao developed a simple but highly effective engineering control: two manual emergency stop–type switches mounted strategically on the right side and rear of the semitrailer. These locations allow tally personnel to activate the system whether working in single or twin tally modes.
When pressed, the switches immediately block the TT’s transmission, neutralizing the vehicle and preventing any gear engagement. Only once tally personnel complete their work and manually reset the switches can the vehicle return to normal operation. This ensures full immobilization whenever someone is in a danger zone.
How It Was Implemented
The maintenance team analysed the electrical circuit of the Transmission Control Module (TCM) to identify the bridge type connector signals responsible for gear engagement. These lines were rerouted through a 7pin connector to the semitrailer, allowing the emergency-stop switches to interrupt the circuit and lock the transmission.
Before approaching the semitrailer, tally personnel activate the switch; after finishing the task, they deactivate it to return control to the operator. To provide immediate visual confirmation, a high visibility LED indicator was installed on the exterior of the cabin: red shows the TT is locked and immobilized; green shows it is unlocked and ready for movement. This ensures clear, shared awareness between operator and ground personnel.
What Was the Result
Operational testing confirmed that activation of the switches reliably blocks the TT transmission under real working conditions. The solution has successfully eliminated unintentional equipment movement during tallying, significantly reducing the risk of serious incidents and improving overall safety performance in the area.
Conclusion
This innovation is low cost, straightforward and highly effective—an engineering upgrade that directly prevents accidents and strengthens safety culture. It demonstrates how maintenance teams can go beyond equipment upkeep to actively drive risk reduction, involve workers in identifying hazards and deliver technological improvements that protect people across critical logistics operations.
- Date
- 20/08/2026
