A mum who lost her 18-year-old son to cardiac arrest has helped launch a scheme to install defibrillators at all Great Northern and Thamselink stations.
Arline Hursey's son James died four years ago, prompting her to set up national campaign group Defibrillators in Public Places.
Govia Thameslink Railway launched the programme last Tuesday, with Knebworth station one of the first places to get the lifesaving equipment.
Arline said: "James was a gentle giant at 6ft 4in with a wicked sense of humour and an all-encompassing hug. His loss was a devastating blow to his family, friends and 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."
The launch event at Welwyn Garden City station involved London Hearts - a charity aiming to put defibrillators in communities - demonstrating how to use the equipment, as well as Great Northern's managing director Tom Moran speaking about their importance.
Mr Moran, who is also a project sponsor, said: "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 to use and will save lives.
"Your chance of surviving a cardiac arrest fall by 10 per cent for every minute without help and a defibrillator can increase chances of survival by 50 per cent."
With only 22 per cent of the UK confident in performing CPR on a stranger, the session aimed to give passers-by the chance to see and learn about their use.
Kimberley Lloyd, London Hearts' head of operations, added: "We are delighted to be working with GTR as they provide lifesaving defibrillators across their rail network.
"It is great to see this investment in the health and wellbeing 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."
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