A nurse is assisting with a community health presentation about home safety precautions when there is an outdoor chemical disaster nearby. Which of the following instructions should the nurse include?

A. Open the dampers of fireplaces. Keeping fireplace dampers open would allow contaminated outdoor air to enter the home, increasing exposure to harmful chemicals. During an outdoor chemical disaster, it is essential to seal the home as much as possible to prevent infiltration of toxic substances. B. Cover heat registers with plastic and tape. Sealing heat registers helps prevent outside air from circulating into the home through ventilation systems. This precaution reduces exposure to airborne chemicals by limiting pathways for contamination. Creating an airtight environment is a key strategy in shelter-in-place recommendations during chemical disasters. C. Exit the home as quickly as possible. Evacuating during an outdoor chemical disaster may increase the risk of exposure if toxic fumes are present. Authorities typically advise sheltering in place with sealed windows and doors unless an evacuation order is issued. Leaving should only occur when officials confirm that it is safe. D. Turn on ceiling fans and air conditioners. Running ventilation systems like fans and air conditioners can draw in outside air, increasing exposure to hazardous chemicals. Instead, all air systems should be turned off to minimize circulation of contaminated air within the home.