A train company is fitting new life-saving equipment into hundreds of stations across its network.

Govia Thameslink Railway (GTR) says it has begun to roll out defibrillators to over 200 stations on its Thameslink, Great Northern and Southern networks, saying the use of the device is “vital”.

Potters Bar station is amongst the first four stations to be fitted with new defibrillators along with Welwyn Garden City, Hadley Wood and Knebworth.

The devices are designed to restore a normal heartbeat by sending an electric pulse or shock to the heart.

And GTR says 90-95 per cent of sudden cardiac arrest victims will die without having a defibrillator to provide immediate treatment.

Project sponsor Tom Moran, managing director of Thameslink and Great Northern, added: “Fitting defibrillators to all our stations is part of our commitment to transform lives and communities. I’m sure passengers will welcome this initiative – these devices are simple and straightforward to use and will save lives.

“Your chance of surviving a cardiac arrest fall by 10% for every minute without help and a defibrillator can increase chances of survival by 50%.”

Helping launch the programme at Welwyn Garden City last week was Arline Hursey, who lost her 18-year-old son, James, to a sudden cardiac arrest four years.

Since then she has set up the national campaign group ‘Defibrillators in Public Places’.

Mrs Hursey said: ““James was a gentle giant at 6'4 with a wicked sense of humour and an all-encompassing hug. His loss was a devastating blow to his family, friends and his community.

“As time is of the essence when it comes to someone suffering from a cardiac arrest, we want to raise awareness and demonstrate to people the ease of using defibrillators within the first couple of minutes. Our vision is for everyone to be able to access a defibrillator within four minutes. It is a vital piece of equipment to saving the lives of our loved ones.”

Also supporting the launch was London Hearts, a heart charity in London for placing defibrillators in communities.

Kimberley Lloyd, London Hearts Head of Operations, said: . “It is great to see this investment in the health and well-being of their passengers and the wider community.

“Nobody in the 21st century should die because they don’t have a heart defibrillator nearby. This initiative is a guaranteed lifesaver which we fully support.”