FDNY COF For Fire Alarm Systems Inspection, Testing And Service Technician (S-98) Practice Exam

Testing smoke detectors must use approved, reliable methods that simulate real smoke in a controlled, repeatable way. Aerosol spray or canned smoke is not permitted for calibration because its particle size, concentration, and distribution can vary greatly and it may leave residues inside the sensing chamber. That can lead to inconsistent results, nuisance alarms, or sensor drift, and it may not be approved by manufacturers or standards. In contrast, a calibrated test instrument provides a known, traceable stimulus; manufacturer-approved test gas can emulate smoke with a defined concentration and properties; and a controlled lab test procedure follows standardized steps to ensure repeatable, accurate verification. So the aerosol spray or canned smoke method is the one to avoid for proper calibration.