tachográf

A tachograph is a device installed in commercial motor vehicles to automatically record driving time, speed, and rest or break periods. It is designed to help enforce rules on drivers’ working hours, reduce fatigue, and improve road safety.

There are two main types of tachographs. Analog (mechanical) tachographs record data on paper discs that rotate while the vehicle operates, with a stylus tracing a graph. Digital tachographs store data electronically in the vehicle unit and on driver and operator cards, allowing information to be downloaded and inspected by authorities. The digital system also provides time stamps and security features to prevent tampering.

In many regions, notably the European Union, digital tachographs are required for most commercial vehicles above a certain weight. They record driving time, rest time, and other work activities, and the data can be retrieved by enforcement agencies using tachograph readers during inspections. The system operates with three cards: a driver card carried by the driver, a vehicle unit installed in the vehicle, and a company or control card that identifies the operator.

Use and scope vary by jurisdiction, but tachographs are widely used in fleets that transport goods or passengers to demonstrate compliance with hours-of-service regulations. Data privacy and security are addressed by access controls and limited retention periods, with access restricted to authorized personnel and regulatory authorities. Critics note cost, maintenance requirements, and concerns about privacy, while supporters emphasize fatigue reduction and consistency in enforcement.