That does not cause undue damage in the event of failure.
Designed to shut off for safety if an emergency occurs.
To compensate automatically, in the event of a failure.
To make a device or mechanism fail-safe, or to add a fail-safe device or mechanism to an existing system.
A device, mechanism or measure designed to make something fail-safe.
Put on trial, taken before a lawcourt.
Tested, hence, proven to be firm or reliable.