This is the horrifying moment a worker had a water tunnel collapse on him during an inspection.
Kai Gillet, a commercial diver from Brighton, Sussex, was carrying out a routine examination to check for cracks, loose bricks, any damage and wear and tear to the structure.
Everything was going to plan for the 27-year-old until the tunnel began to cave in on him - and he had a battle on to get out alive.
Thankfully he stayed calm and escaped without injury but knows on another day things could have been very different.
He always films his inspections to include in the report so the camera was able to pick up everything that happened.
So he decided to upload the footage to social media and it gathered plenty of interest.
The video blew up on TikTok reaching over eight million views with hundreds of people asking if he is ok.
Kai said keeping composed gave him the chance to tell his story - and pick up plenty of new followers!
"Everything happened extremely fast, understandably it's easy to panic in those kinds of situations, but you have to remain focused on your breathing and staying calm," he explained.
"Especially if you're in a situation where air is a main priority.
"Figuring out what you need to do step by step and coming up with a plan to get out safely is very important.
"The video has gone absolutely crazy - it has been seen by over eight million views and still climbing.
"I never imagined the kind of reaction it would have.
"I've had so many people message me, reaching out to make sure I'm a okay which is lovely.
"I've also had a lot of people asking me about diving and how to get into a career in the industry."
