THE Rail Accident Investigation Branch (RAIB) will publish a safety digest following the derailment of a train in Penryn last week.

A passenger train consisting of two coaches became derailed by the leading bogie - the undercarriage - at a set of points at 12.36pm on January 28.

The train was travelling at around 15mph at the time.

The accident resulted in minor damage to the track, and there were no injuries to passengers, who were able to alight on the platform at Penryn station.

A tweet from the RAIB stated: "We have undertaken a preliminary examination into the circumstances surrounding this incident. Having assessed the evidence which has been gathered to date, we have decided to publish a safety digest.

"The safety digest will be made available on our website in the next few weeks."

The RAIB's web page adds: "When it is clear that the safety learning from an event has been identified by a previous investigation or relates to compliance with existing rules, we may choose to publish a safety digest, rather than carry out a full investigation."

The railway industry notifies the RAIB of many accidents, incidents and near misses each year, but not all of them are investigated. Various criteria is used to help them decide which ones they will look into.

The law requires investigations to be made involving train collisions and derailments which result in the death of a person, or serious injury to five or more people, or damage costing more than €2m to repair.

The law offers discretion as to whether or not to investigate less serious accidents.

When they decide whether to investigate these, various factors are taken into consideration.

These include:

* the severity of the outcome

* the potential for the consequences to have been more severe

* the potential for new safety learning, and how widely it could be applied

* safety trends

* areas of particular safety concern.