Legal basis in one paragraph
Recording is processing under GDPR. Lawful basis is usually legitimate interest, balanced against the individual. Signage, policy, retention limits and access controls make it defensible.
Announcing the record
'This interaction is being recorded on body-worn video for your safety and mine.' Simple, calm, non-threatening. Behaviour usually improves immediately.
Post-shift
Docking station handover, no personal-device transfer, no cloud upload outside employer-approved system. Any deviation is a data breach in waiting.