Safety driving circuit (Sifa) or the dead man’s handle

They are integrated into chainsaws, lawnmowers and kitchen shredders - as well as in our traction units: Dead man’s handle, otherwise known as a safety driving circuit (Sifa). Dead man’s handles are either installed into work equipment or vehicles, and some models can even be attached to a person’s work clothes. They provide additional protection in working areas where particular concentration is required.

What does a Sifa or dead man’s handle look like in our locomotives?

The safety circuits in our traction units are usually integrated as a pedal on the ground or as a lever on the dashboard so the driver is always close to it. During the length of the journey, they must stand on the safety pedal and briefly release it every 30 seconds. Alternatively, they can also press the lever every 30 seconds. Important: both safety devices must never be operated at the same time, so the train driver must decide whether to use the pedal or the lever. This shows that they are awake and alert whilst at work. This is an important matter, as ultimately our drivers have a high level of responsibility: Ultimately, the safety of goods but also potential other passengers, is in their hands. As they work alone in the driver’s cabin, their reliability and ability to react must be unwavering at all times.

Automatic braking takes place after a pre-alarm

If the safety driving circuit (Sifa) or dead man’s handle is not actuated, an acoustic warning signal is emitted. If the driver does not respond to this pre-alarm, automatic braking takes place. If the driver has fallen asleep or is unconscious, this proven mechanism can prevent injuries and damage to property.

However, it is not absolutely clear how this piece of equipment got its name: There is a theory that the name for the German word “Totmannschalter” is derived from Edward D. Totmann, who is considered to be the inventor of this safety mechanism in English-speaking countries.