That sweet sweet nicotine.

> The real danger of allowing smoking on a hydrogen airship — and the reason it was strictly confined to the closely monitored smoking room — was the risk of a fire;

I'd say... contrary, allowing smoking in a dedicated controlled place was the safer option. The real danger was not allowing smoking because if you ban smoking, people will smoke no matter if it's banned - and back then, there were a looooot more smokers, so a loooooot more opportunities for someone to behave utterly braindead.

That's also why every modern airplane to this day has ashtrays in the lavatory. There WILL be someone smoking at some point, and better provide them with a safe option to discard the butt than risk having the person throw the butt in the trash bin where it can set the waste ablaze.