What defines a radiological incident?

A radiological incident is specifically defined as an event that leads to the release of radioactive materials, necessitating emergency response. This definition is crucial because it emphasizes the potential for harm associated with the uncontrolled release of radioactive substances. Such events can pose significant risks to public health and safety, requiring immediate action to contain and mitigate the effects of radiation exposure on individuals and the environment.

In this context, other options lack the critical components that qualify as a radiological incident. For instance, events without risk or consequence do not meet the criteria since they do not involve any potential harm. Similarly, incidents related specifically to radiation therapy are generally controlled situations within medical settings and do not typically involve the uncontrolled release of radioactive materials. Lastly, testing of radiation monitoring devices is routine operational procedure and does not imply any incident involving radiological hazards. Thus, the necessity for emergency response and the potential for hazardous release are fundamental aspects that distinctly characterize a radiological incident.