Hmmm, think you'll find that the Royal Parks are a little more stringent about requirements for large events held in their grounds!
see below (from their events guidelines doc):

"6. Local consultation and liaison with other public authorities

The Royal Parks consults with people and businesses affected by events in our parks. We will coordinate local consultations about your event and will ask for your support in this process.

We will also assist you in working with other public organisations that will have an involvement in your event, such as the Police, Fire Brigade, Ambulance Service, local authority and transport providers. We hold regular Licensing & Safety Advisory Group (LSAG) meetings with these other authorities, which you may need to attend."


Not to mention Royal Parks requirement for organisers to have: event production manager, stewarding and security firms, health and safety consultant, site manager and event suppliers (staging, lighting, toilets....lets not even go there in terms of what happened inside AND outside the Horniman grounds this year due to lack of loos - disgusting)

Something else the museum management could learn from......