Canadian transport watchdog to launch safety investigation; Stockton Rush reportedly emailed deep-sea expert saying concerns were ‘baseless cries’

• Full report: Investigations under way as questions grow over design

William Kohnen, chairman of the Manned Underwater Vehicles Committee, said the regulations for building submersible vessels were “written in blood”.

Kohnen’s organisation, based in Los Angeles in the US, raised safety concerns in 2018 about OceanGate’s development of Titan.

We’re only smart because we remember what we wrote and what we did wrong last time.

The rules are written in blood – it is in there because it caused trouble before, and to say: ‘Well I think we’re just going to ignore that and go on our own way,’ suggests there might be a bit of input of wisdom that this might not be the best decision.

It’s too early to tell, there’s data that’s going to have to be collected over the coming days, weeks and months, and I’m sure the team will work with whoever is conducting the investigations to cooperate and provide as much information as possible.

At that point, we’ll be in a better position to tell (what went wrong).

There are regulations in place but as you can imagine there aren’t many subs that go that deep, so the regulations are pretty sparse and many of them are antiquated and designed for specific instances.

It’s tricky to navigate those regulatory schemes.