Below is a copy of Graemes presentation, from 12th June 2013:
You may also find the two documents below of interest:
NARU latest guidance on Triage Sieve
Ambulance Command and Control Booklet
This is an excellent guidance on how to deal with major and critical incidents. A must read in addition to your trusts Major Incident plan.
naru.org.uk has some excellent resources for ambulance service resilience and major incidents.