Opening questions
"Why security, why us, why now" — three-part answer, one minute total. Employers hire for reliability first, personality second, skills third.
Competency questions
Use STAR: Situation, Task, Action, Result. Prepare three examples that flex across most competencies (Perimeter checks, Plant theft awareness, PPE compliance, Fire watch).
Give the outcome as a number where you can (incidents, minutes, hours).
Scenario questions
"A visitor becomes aggressive at reception — walk me through it." Answer with position, communication, escalation and record — not just physical intervention.
Licence and vetting
Bring the physical SIA Security Guard licence + CSCS card recommended to the interview. Have address history for the last five years ready. If there is anything to declare, declare it up front — discovery downstream costs the job.
Your questions back
Rota pattern, welfare check frequency, training budget, on-site amenities, dispute-resolution process. Silence at "any questions?" reads as disinterest.