A nurse is among the first responders to a mass-casualty incident and does not know what type of personal protective equipment (PPE) is needed. Which of the following actions should the nurse take?

Rationale: A. Decontamination is critical in chemical, biological, or radiological events, but it must be performed after the responder is properly protected. Intervening without appropriate PPE could put the nurse at risk of contamination. B. This is unsafe. Delaying intervention can endanger victims and is not an appropriate immediate response. The nurse must act quickly but safely, using available knowledge and resources to protect themselves and others. C. This is partially correct in a radiation scenario, but in an urgent mass-casualty event, waiting to measure radiation can delay critical care. If a dosimeter is unavailable, the nurse must prioritize personal protection while responding. D. When the required PPE is unknown, nurses should opt for the highest level of protection available to minimize personal risk while providing care. This includes fully encapsulating suits, respirators, gloves, and eye protection. Using the maximum PPE ensures the nurse can safely respond until the hazard type is clarified.