Hydrogen is little different to natural or town gas for explosion risk. I expect politicians are relying on a good proportion of the population to be too knee-jerk to realise this.
I appreciate that Hydrogen has a lighter atomic weight and is simpler than the other two, thus slightly more difficult to store, but we hear of gas explosions all the time.
Anyhow this is nautical forum so, I will read the articles. If using conventional engines, there is an issue with hydrolysing the cylinders and pistons making them brittle over time, so an additive needs to be mixed with the hydrogen to reduce/prevent this.