Reducing false alarms — what strategies actually work?

Unwanted fire signals are still the single biggest frustration for end users and the fire service. BS 5839-1 Clause 35 gives the framework, but every building is different. I would be interested to hear real-world approaches — things like: - Swapping from optical to multi-sensor detectors in cooking-adjacent areas - Using delay or investigation mode at staff-occupied premises - Improved maintenance regimes for old detectors - User training so people stop burning toast directly under the sensor What has reduced false alarms at sites you look after?