What phrase is used to indicate a person requires immediate medical assistance?

The phrase "Man Down" is commonly used in emergency responses to indicate that a person is in need of immediate medical assistance. It is a clear and direct call for help, effectively communicating the urgency of the situation to responders. This terminology is critical in situations where every second counts, ensuring that dispatch and other units understand that a person's life may be at stake, and swift action is required.

While "Security Check," "Possible Dead Body," and "Check on welfare of" may indicate various situations requiring attention, they do not convey the same immediate need for urgent medical assistance. "Security Check" suggests a routine review or verification, "Possible Dead Body" pertains to a potential fatality without indicating that immediate medical aid is needed, and "Check on welfare of" may describe a general concern for someone's well-being, which does not necessarily imply a life-threatening condition. Therefore, "Man Down" stands out as the most appropriate phrase for indicating the urgent need for medical help.