US 12,283,175 B2
Monitoring an aerosol density level in a fire sensing device
Benjamin H. Wolf, Leicester (GB); Christopher Dearden, Melton Mowbray (GB); and Michael Barson, Nuneaton (GB)
Assigned to Honeywell International Inc., Charlotte, NC (US)
Filed by Honeywell International Inc., Charlotte, NC (US)
Filed on Jul. 13, 2023, as Appl. No. 18/221,675.
Prior Publication US 2025/0022361 A1, Jan. 16, 2025
Int. Cl. G08B 29/00 (2006.01); G08B 17/107 (2006.01); G08B 29/04 (2006.01); G08B 29/14 (2006.01)
CPC G08B 29/145 (2013.01) [G08B 17/107 (2013.01); G08B 29/043 (2013.01)] 20 Claims
OG exemplary drawing
 
9. A method for operating a self-testing fire sensing device, comprising:
generating aerosol using an adjustable particle generator of the self-testing fire sensing device;
generating airflow to move the aerosol through an optical scatter chamber of the self-testing fire sensing device using a variable airflow generator of the self-testing fire sensing device;
measuring an aerosol density level of the aerosol in the optical scatter chamber;
stopping the adjustable particle generator from generating the aerosol responsive to the measured aerosol density level increasing to a threshold aerosol density level;
measuring an additional aerosol density level of the aerosol in the optical scatter chamber responsive to stopping the adjustable particle generator from generating the aerosol; and
stopping the variable airflow generator from generating the airflow responsive to the additional measured aerosol density level decreasing to a baseline aerosol density level.