A disaster is an event that overwhelms a community's ability to respond with its usual resources. Disasters can be natural (hurricanes, floods, wildfires, earthquakes, tornadoes, heat waves, pandemics) or human-made (chemical releases, explosions, transportation crashes, mass shootings, terrorism). A mass casualty incident (MCI) occurs when the number or severity of casualties exceeds immediately available medical resources — demand for care is greater than supply.

Disaster management cycle (the same four phases used in the Medical-Surgical disaster topic)

The federal National Preparedness Goal describes five mission areas: prevention, protection, mitigation, response, and recovery, and emphasizes a "whole community" approach — government, health care, businesses, faith groups, volunteers, and residents all share responsibility.

Risk and vulnerability: disaster risk rises with the hazard and with the community's vulnerability, and falls with its capacity to cope. Vulnerability depends less on average income alone than on factors such as stable income sources, access to health care and information, transportation, language, disability, chronic illness, dependence on electricity-powered medical devices, and social support networks.

People with access and functional needs — older adults, children, pregnant women, people with disabilities or chronic illness, people with limited English, people experiencing homelessness, and people dependent on dialysis, oxygen, or other power-dependent equipment — need planning before the event, not improvised help after it.

National Incident Management System (NIMS) — a common, all-hazards approach so agencies at every level work together. Its components are resource management; command and coordination; and communications and information management.

Incident Command System (ICS) — the standardized, scalable on-scene structure within NIMS:

• Incident Commander (or unified command when several agencies share authority), supported by command staff: Public Information Officer, Safety Officer, Liaison Officer.
• General staff sections: Operations, Planning, Logistics, Finance/Administration.
• Principles: unity of command (one supervisor per person), manageable span of control, common terminology, clear objectives, and integrated communications. Hospitals use the Hospital Incident Command System (HICS).

National frameworks and resources

Triage in MCIs (details in the Medical-Surgical triage topic): START for adults — walking → Green; not breathing after airway repositioning → Black; breathing only after repositioning, respiratory rate > 30/min, no radial pulse or capillary refill > 2 seconds, or cannot follow simple commands → Red; all others → Yellow. JumpSTART is used for children and SALT is an alternative. The goal is the greatest good for the greatest number.

International disaster relief principles

• Humanitarian principles: humanity, neutrality, impartiality (aid according to need, prioritizing the most vulnerable), and independence — essential in conflict zones for access and safety.
• Sphere standards: a Humanitarian Charter and minimum standards for water, sanitation, and hygiene; food and nutrition; shelter; and health, to improve the quality and accountability of relief.
• Cluster approach: lead agencies coordinate each sector (health, water and sanitation, shelter, nutrition) to avoid gaps and duplication.
• The first step on arrival is a rapid needs assessment; sustainable relief builds local capacity by training local health workers before teams leave.

Preparedness

• Map hazards and identify vulnerable residents (people who need power for oxygen or ventilators, dialysis clients, homebound older adults, group homes) and local resources (shelters, generators, pharmacies, volunteers); keep the list current.
• Teach households to make a plan (meeting place, out-of-area contact), build a kit (water, food, flashlight, radio, batteries, first-aid supplies, documents, and a supply of prescription medicines with a written list), and sign up for local alerts.
• Participate in drills and tabletop exercises; know your role in the agency plan. Nurses need their own family plan so they can report to work.

Response

• Safety first: at a chemical release, stay upwind and uphill, do not enter the contaminated (hot) zone, and wait for trained hazmat teams.
• Report to the incident command structure and accept an assignment — do not self-deploy.
• Rapid needs assessment: casualties, damage, water and sanitation, shelter, health service disruption, and the most vulnerable groups.
• Shelter health:
  • Hand hygiene is the most important measure against outbreaks in crowded shelters; add adequate ventilation, space between cots, cleaning, and isolation areas.
  • Watch for clusters of fever and cough — respiratory infections such as influenza spread fast in crowded shelters — and of diarrhea (norovirus) and rash.
  • Safe water and food: keep cold food at 40°F (4°C) or below; discard food left unrefrigerated too long.
  • Continue chronic disease care: insulin, antihypertensives, dialysis access, oxygen, psychiatric medicines.
  • Warn against using generators, grills, or camp stoves indoors (carbon monoxide).
• After floods, the most urgent education is safe drinking water — boil or disinfect water or use bottled water until authorities declare it safe; avoid floodwater contact, clean wounds, and seek care for fever.
• Psychological first aid: ensure safety and comfort, meet basic needs, give accurate information, connect people with family and services, and never force people to describe the traumatic event.
• When communication systems fail: use backup systems (radios, runners), share collected information with the team, and coordinate decisions and resources locally within the command structure.

Recovery

• Restore routine public health services: immunization, prenatal and chronic disease care, and clinic reopening.
• Monitor mental health (depression, PTSD, substance use) and refer; community rebuilding and social support aid resilience.
• Conduct an after-action review and update the plan — recovery links back to mitigation.

• Planner: helps write community and agency plans; identifies vulnerable populations and resources.
• Educator: teaches personal preparedness and public health measures.
• Responder: triage, first aid, shelter nursing, medication continuity, surveillance, mass vaccination or prophylaxis at points of dispensing.
• Coordinator and communicator: works within ICS, reports data, links clients to services.
• Advocate for vulnerable groups: assesses their specific needs and mobilizes community resources for them.
• Role expansion: in disasters, nurses may take on broader responsibilities, but only within their education, training, and legal scope as authorized by emergency orders and protocols.
• Self-care and team care: responders face secondary traumatic stress and burnout; manage it with rest, nutrition, shift rotation, and peer support, and use employee assistance and mental health services.

• Licensure: a nurse's license is state-based. A nurse with a multistate license under the Nurse Licensure Compact may practice in other compact states at any time; in a declared disaster, the Emergency Management Assistance Compact between states and state emergency orders can extend recognition further. Volunteer through organized systems (Medical Reserve Corps, state registries, the Red Cross) rather than self-deploying.
• Crisis standards of care: when resources are critically scarce, care shifts to population-focused, protocol-driven allocation approved in advance; nurses follow these protocols and document decisions.
• Duty to care versus personal risk: nurses have an ethical obligation to respond, balanced with protecting themselves and their families; plans should address this in advance.
• HIPAA remains in effect in disasters, but it permits sharing necessary information for treatment, with public health authorities, and with disaster relief organizations to locate and notify family.
• Justice: allocate scarce resources fairly and by need; do not discriminate on the basis of disability, age, race, or ability to pay.
• Documentation continues, even in simplified form (triage tags, casualty tracking).

Case 1 — Preparedness priority. A health department asks community nurses how to prepare for hurricane season. Correct action: build and update a registry of residents who depend on power, dialysis, or home health, and an inventory of shelters and supplies. Why: knowing who is vulnerable and what resources exist makes rapid, targeted response possible.

Case 2 — Shelter fever cluster. Three days after an earthquake, several evacuees in a crowded shelter develop fever, cough, and myalgia. Correct action: suspect influenza or another respiratory infection, separate symptomatic people, reinforce hand hygiene and respiratory etiquette, report to public health, and arrange testing and treatment. Why: crowding spreads respiratory droplets quickly.

Case 3 — START. A man at a bus crash cannot walk, is breathing at 34 breaths per minute, and has a radial pulse. Correct tag: Red (immediate). Why: a respiratory rate above 30 meets the Red criterion.

Case 4 — Chemical spill. A community nurse arrives near an overturned tanker with a strong odor and people coughing. Correct action: stay upwind and uphill at a safe distance, call for hazmat, and help direct people away; do not enter the area. Why: rescuer safety comes first, and an injured nurse becomes another casualty.

• Placing vulnerability analysis or long-term rebuilding in the response phase — they belong to mitigation, preparedness, and recovery.
• Self-deploying to a disaster scene instead of working through ICS or organized volunteer systems.
• Tagging a person who is not breathing Red — if breathing does not start after airway repositioning, START assigns Black.
• Forcing survivors to retell their experience — this is not psychological first aid.
• Distributing aid equally rather than according to need.
• Leaving local communities dependent on outside teams — build local capacity.
• Assuming HIPAA is suspended in disasters.
• Ignoring responders' own stress.

• Disaster cycle: mitigation → preparedness → response → recovery
• Preparedness: plans, drills, vulnerable-population registry and resource inventory
• Recovery: restore routine health services (immunization, chronic disease care), mental health, after-action review
• NIMS/ICS: Incident Commander; Operations, Planning, Logistics, Finance/Administration; unity of command
• ESF 8 = public health and medical support; Stafford Act declarations unlock FEMA aid
• SNS 12-hour push packages; CHEMPACK for nerve agents; MRC and DMATs
• START Red: RR > 30, no radial pulse or CRT > 2 s, cannot follow commands, or breathes only after repositioning
• Shelter infection control: hand hygiene first
• After floods: safe drinking water first
• Chemical release: upwind and uphill; never enter the hot zone
• PFA: safety, comfort, basic needs, connection; no forced retelling
• Humanitarian principles: humanity, neutrality, impartiality, independence; Sphere minimum standards; cluster coordination