Methods and apparatus relate to control of smoke suppressant flow rate to a flare that disposes of combustible gas, such as waste from refineries and chemical plants. One or more detectors produce signals that enable separate monitoring of both particulate emissions from the flare and combustion efficiency of the flare. Adjusting the flow rate of the smoke suppressant to the flare in response to such dual monitoring facilitates operation of the flare so as to manage environmental pollution caused by unburned volatile organic compounds and smoke emitted from the flare.