One embodiment of an applicator comprises a brush head with a ferrule, and a brush handle. A dry calcium hydroxide powder is injected into the gas flowpath and hydrated in the spray dryer absorber. The stator has a stator core including a yoke and nine poles extending from the yoke. In one embodiment, the contact surfaces of the silicon contact are plated in gold and are planar. An initial second reading voltage is determined on the basis of the final first reading voltage.