D181

Visually inspect detector lens and chamber for dust, insect contamination, or corrosion buildup. Clean or replace detector if optical transmission is compromised (use magnifying glass for small particulates).

Perform semi-annual sensitivity testing using manufacturer-approved calibration tools (e.g., NSTT-C for SIJ-24 series). Verify detector responds within listed sensitivity range (typically 25%-70% obscuration for photoelectric). Replace if sensitivity cannot be recalibrated.

Verify detectors are properly seated in bases (confirm clockwise twist-lock engagement). For beam detectors, confirm alignment within reflector center using motorized alignment verification. Check mounting hardware security and absence of vibration-induced looseness.

Verify electrical connections at detector base and wiring terminals. Test continuity to control panel. For conventional detectors, confirm 24VDC supply voltage at detector head. For addressable detectors, test SCI loop continuity and polling response.

Inspect for sources of nuisance triggers: proximity to HVAC ducts, direct sunlight on beam detectors, steam/condensation sources near smoke detectors, or electromagnetic interference near addressable loops. Reposition detectors or install optical filters as needed per EN54 standards.