I have followed this sad story with interest.
Regarding the accident itself, I only know what I've read in the media, so I cannot speculate on any of the circumstances surrounding it. Given that this poor chap was killed in what seems to have been a workplace accident, would it be normal for the HSE to do an investigation and compile a detailed report? Perhaps, in the future, this report might be available so that others can learn whatever lessons can be drawn from the tragic circumstances.
As a aside, this is not a comment on the above, I am a relative beginner in woodturning. One of the best pieces of advice I got (on here) was to include for PPE in my initial budget. For PPE, I have various safety glasses, goggles and dust masks that I use for 'ordinary' woodwork and DIY. For woodturning, I decided to bite the bullet and bought a Trend Airshield respirator which gives a good level of head protection with the 'helmet' and visor. I always wear it whilst turning. Always.