These well known organisations provide excellent advice on how to prepare for and act during emergencies:
The Ambulance Service
The Association of Insurance and Risk Managers in Industry and Commerce
Bournemouth University Disaster Management Centre
British Red Cross
HM Coastguard
The Environment Agency
The Fire Brigade
The Met Office
Mountain Rescue
NHS
The National Preparedness Commission
The Police
The Resilience Academy
The Royal National Lifeboats Institute
The Royal Society for the Prevention of Accidents