In the context ofMass Care and Sheltering(Emergency Support Function #6), housing is categorized based on its intended use and the speed of deployment.Ships and trainsare consideredunconventional housingbecause they were never designed for long-term residency and require extreme logistical coordination to serve as safe shelters. While they offer high capacity, they present significant challenges in terms of hygiene, medical access, and the psychological "enclosure" of the victims.

In contrast, Schools and Public Facilities (Option A) are considered "Traditional" or "Congregate" shelters and are the primary focus of most local Emergency Operations Plans (EOPs). Tents and prefabricated buildings (Option B) are considered "Transitional" or "Temporary" housing. Using ships (such as cruise ships) has been done in rare circumstances, such as during the response to Hurricane Katrina or for housing workers during large-scale recovery efforts, but it is never the "preferred" or conventional route.

According to theIBFCSM CEDPguidelines, unconventional housing options are only explored when the "Traditional" and "Transitional" options are completely exhausted or the environment is too toxic for land-based sheltering. Using ships or trains requires specialized safety inspections (Coast Guard or FRA regulations), dedicated waste management systems, and a plan for "Total Evacuation" of the mobile housing unit itself if a secondary disaster occurs. Disaster professionals must weigh the high cost and logistical complexity of these unconventional solutions against the urgent need for climate-controlled, safe environments for displaced populations.