These include:

(a) Plant closures;

(b) Mass layoffs affecting 50 or more workers at a single site of employment;

(c) Closures and realignments of military installations;

(d) Multiple layoffs in a single local community that have significantly increased the total number of unemployed individuals in a community;

(e) Emergencies or natural disasters, as defined in paragraphs (1) and (2) respectively, of section 102 of the Robert T. Stafford Disaster Relief and Emergency Assistance Act (42 U.S.C. § 5122(1) and (2)) which have been declared eligible for public assistance by the Federal Emergency Management Agency (FEMA); and

(f) Other events, as determined by the Secretary.