LSSD's may be classified into two main categories – natural disasters such as earthquakes, tsunamis, forest fires, floods, volcanic eruptions, etc., and manmade disasters such as hazardous materials leaks, nuclear plant accidents, fuel tank explosions, ecological contamination, war, sabotage, etc. Whereas manmade disasters can at times be prevented, and at other times their harm can be greatly lessened, natural disasters cannot be avoided, and often cannot be foreseen with reasonable accuracy.
However, for both categories of disasters it is possible to prepare in advance in a way that would drastically reduce the number of casualties and the scale of damage.
The lack or existence of early preparation and contingency plans for such emergencies will make the difference in whether the government, organization or company will be able to continue their activity in the fields that they define as critical, and in whether they will be able to survive the event.
This area of expertise has evolved out of the heavy cost to countries, companies and organizations from disasters, and from the understanding that a unique specialty would be required to prepare for a disaster, reduce its potential damages in advance, manage and coordinate the various forces that operate during the event, and strengthen the community and the organization's ability to recuperate following the disaster.
In recent years the field of disaster studies has emerged as a new academic field.
Specialization in disaster management includes all three stages (before, during and after) – risk analysis and contingency planning, management and coordination during the event, and a disaster recovery plan.
When it comes to countries, services will focus on preventing casualties, protecting infrastructure and preserving community structures. For organizations and companies, both in the private and public sector, we will focus on continuity of business operations.
The Homeland Security Academy establishes seminars, study days and conventions in the subject in order to enable the trainees to understand the challenges that managers and leaders are facing in emergencies that emerge from LSSD's and to evaluate the tools, techniques and material resources that are needed in order to confront with the consequences.