Calibration of a heating element in a fire sensing device

A self-testing fire sensing device, comprising:

• a heating element;
• a reservoir comprising liquid or wax;
• a variable airflow generator;
• and
• a controller configured to:
• receive a characteristic of the heating element, wherein the heating element is a wire, and wherein the characteristic of the heating element is a material of the wire, a length of the wire, or a diameter of the wire that varies as a result of variabilities in manufacturing the heating element;
• and
• apply a calibrated electrical heating input to the heating element based on the characteristic of the heating element;
• wherein the heating element is configured to heat the liquid or wax to generate a particular amount of aerosol or gas responsive to the calibrated electrical heating input;
• and
• wherein the variable airflow generator is configured to:
• move the particular amount of aerosol or gas through the self-testing fire sensing device;
• and
• return the self-testing fire sensing device to a state prior to generating the particular amount of aerosol or gas.