One thing to consider that if your club currently carries public liability insurance and there are no exclusions for steam powered models then you have cover already. Lots of insurance case law, if its not specifically excluded then its covered for such insurances.
[size=78%]In my opinion far to much concern is expressed over steam models and their danger, if any. The concern always seems to be what happens if a boiler explodes, like a hand grenade going off! No, actually and in 40 years of modelling I have never unearthed an genuine case of a model marine boiler exploding (Note I'm talking small boilers such as made in the past by Cheddar models that only carry about 500mm of water).[/size]
Cheddar actually tested one to destruction years ago by sealing off all vents and steamed it to destruction. I don't know what the pressure was but eventually the end plates bulged and one of the joints on an internal fire tube split and a jet of steam vented and put the flame out. No explosion, it just doesn't happen.
Another myth is that if you run out of water before fuel the boiler can explode. No it cant, no water = no pressure = no explosion! Its scientifically impossible. Yes you can set fire to the model but that's about all.
In my opinion very fast electrics are far more dangerous, fast enough to hit the bank and fly into the air .(and hit people) with their razor sharp props spinning at god knows what rpm.
Just enjoy your hobby.
Cheers
Geoff