In reply to Tigger:
Also to say, never think your skill set is too niche. Whilst your very specific technical skills might be niche at the moment you will have a much wider set of transferable skills. The very fact you are working in a technically demanding area under, I assume, quite demanding health and safety regulations is actually very generic. I am sure you could quickly retrain into the specific technical needs of different industries.
Try to brainstorm the more generic skills you have and think outside the box. It is not easy to do but I am sure you will surprise yourself about what you can offer other industries. I am a big fan of using skills in different areas as you develop and the new company benefits from a different perspective. It is all about how you sell yourself.
And, don't forget the skills and mindset you have developed from being a climber. It takes a certain determination and dedication to climb to the level you have got. Again, it is all about how you sell this on a CV.
With all this you can easily make yourself stand out from the crowd.
I recommend getting someone else who knows you to look over your CV with a fresh pair of eyes to help draw out some of these things.