Please describe a sporting arena. There are many different types. Do you mean a structure like the NEC at Birmingham or perhaps a covered stadium like the Millennium Stadium at Cardiff?
In any event the venue will have a generic fire strategy that will involve developed strategies for running the event together with fixed installations etc. of some description particularly indoor arenas. This may mean anything from AFD through to sprinklers.
For specific uses each event will be subject to Risk Assessment.
The event is controlled through the Licensing Authority, usually the local council. They will have a safety certificate issueing team consisting generally of the Licensing Officers, Building Control, Police and Fire Service personnel. Dont forget that even with all these it is still aplace of work and therefore subject to the Workplace Regulations.
If what is proposed is not satisfactory then the event does not get it's licence.
Motor shows for example will have cars that do not have fuel (generally).