This European standard comprises safety requirements and test methods for safety shut-off devices in combustion plants, which on opening release, with or without delay, the flow of the fules mentioned below and shut off without delay on closing. This standard applies to the use of fuel oils. For other liquid fuels the test methods may be agreed between the manufacturer and the test institute. This standard also applies to safety shut-off devices forming part of devices having other functions, i.e. oil pumps. In this case the test methods apply to those parts or components of the device forming the safety shut-off device, i.e. those parts which are necessary for the closing function.