Northy beat me to it!!
Kyosho-viking - please refer your Association to an accident we had here. A young driver was badly injured when a battery accident happened right in their face as they were looking at... a Nitro car!! The battery was for powering the Nitro electrics.
I hope that you are protesting to your Association. This is a ridiculous over-reaction. If the concern is safety, then all RC racing should be stopped, as all RC racing is using NiMH batteries. I hope you can get this decision reversed.
Anyone imagine what would happen if the BRCA tried to do this?
springs to mind...!!