The moment the call comes in
Stay calm. Take the call somewhere quiet if possible. Record if system allows. Signal a colleague to alert supervision without hanging up.
The NPSA checklist
Use the NPSA Recognised Standard Bomb Threat Checklist. Record every word, background noise, accent, gender, time of call. This is evidence.
Escalation lines
Simultaneous notification to 999 police, site senior lead and (where relevant) the corporate security operations centre.
Evacuation vs invacuation
Specific threat with credible detail: evacuate away from the threat area, not towards it. Generic threat with no specifics: consider invacuation to a safer part of the building.
Post-incident actions
Preserve the call recording, submit witness statement, cooperate with police, review the incident with all staff within 72 hours.