What is the fourth action in the non-fire emergency actions besides in-building relocation, partial evacuation, and full evacuation?

The fourth action in non-fire emergency responses, following in-building relocation, partial evacuation, and full evacuation, is to shelter in place. This action is crucial in scenarios where it may not be safe to exit a building or area due to various emergencies, such as hazardous material spills, active shooter situations, or severe weather events. By sheltering in place, individuals are instructed to remain indoors and take specific steps to protect themselves until the danger has passed or they receive further instructions from emergency services.

Sheltering in place typically involves finding a safe location inside the building, securing windows and doors, and staying informed through available communication channels. This action helps ensure the safety of individuals by minimizing their exposure to potential threats outside.

The other options represent different emergency management strategies that are not suitable for every scenario. For example, "stay indoors" is somewhat vague and does not provide the specific protective measures that "shelter in place" entails. "Lockdown" applies mainly in situations like active threats where individuals are explicitly advised to lockdown to prevent access to the premises. "Signal for help" might be necessary in certain situations but doesn't provide a comprehensive response strategy like sheltering in place does.