"airport airside risk assessment" on Google turns up quite a few PDFs, in particular a risk assessment for refulleing operations and staff involved there in, and Risks associated with attending and airside incident for Hampshire police officers.
You've probably looked at these already but they should provide a starting point.
We have an aviation recruitment division - I'll see if there's anything which we might have access to which I'd be allowed to distribute.
Cheers,
Duncan