As used in this article, "emergency services" means the preparation for and the carrying out of all emergency functions, other than functions for which military forces are primarily responsible, to prevent, minimize and repair injury and damage resulting from disasters caused by enemy attack, sabotage or other natural or other man-made causes. These functions include, without limitation, fire-fighting services, police services, medical and health services, communications, radiological, chemical and other special weapons defense, evacuation of persons from stricken areas, emergency welfare services, emergency transportation, existing or properly assigned functions of plant protection, temporary restoration of public utility services and other functions related to civilian protection, together with all other activities necessary or incidental to the preparation for and carrying out of the foregoing functions. Disaster includes the imminent threat of disaster as well as its occurrence and any power or authority exercisable on account of a disaster may be exercised during the period when there is an imminent threat thereof.