A tachograph displays vehicle speed and makes a record of all speeds during an entire trip. The name ‘tachograph’ comes from the graphical recording of the tachometer or engine speed.

Analogue units record the driver’s periods of duty on a waxed paper disc – a tachograph chart. An ink pen records the engine speed on circular graph paper that automatically advances according to the internal clock of the tachograph. This graph paper is removed on a regular basis and maintained by the fleet owner for government records.

In the 1950s, there were an increasing number of road accidents attributed to sleep-deprived and tired truck drivers. Concerns for safety led to the rapid spread of the tachograph in the commercial vehicle market, but at this point it was voluntary and not legislated.

Fleet operators then found that tachographs helped them to monitor driver hours more reliably, and safety also improved. In Europe, use of tachographs has been compulsory for all trucks over 3.5 tonnes since 1970.

For safety reasons, most countries also have limits on the working hours of drivers of commercial vehicles. Tachographs are used to monitor drivers’ working hours and ensure that appropriate breaks are taken.

Legislation relating to Tachographs has been in force in the UK for 16 years. The tachograph is now an indispensable tool for managing fleets and ensuring the safety of drivers of commercial vehicles.

As of 1st May 2006, Analogue tachographs are being phased out in favour of digital versions which record data on a smart card. Find out more.