Who are the officers who are responsible for staying alert for breaches in prison discipline or regulations in the relatively unstructured environment of the prison yard?

The answer that is being described above is the yard officers. They are the ones that are always and should always be alert because of possibility of having breaches in prison such as in regulations or discipline. The yard officers has the most stressful and dangerous job even though they are termed to have the least seniority in the officers.