A brush for dislodging impurities on steam relief screen basket within an operating vessel including at least one brush that includes an elongated support column with a brush attached to a first end of the elongated support column extends out of a seal located on a removable vessel cover of the vessel. The steps using the brush to dislodge impurities on steam relief screen basket include locating the brush comprised of a plurality of bristles adjacent to the steam relief screen basket, contacting the brush with the screen basket, extending the elongated support column through the seal, closing the removable vessel cover of the vessel to avoid pressure drop inside the vessel, and moving the brush from a first location on the screen basket to a second location on the screen basket to dislodge impurities attached to the screen basket.