Present embodiments of the disclosure are directed to a seal assembly for generating a seal between two opposing shear blades of a ram unit after shearing a tubular. The seal assembly may include at least a wiper, a sealing element, and an energizer. The wiper may clean a surface of a shear blade as the blade moves relative to the seal assembly. The sealing element may include an elastomeric material that can be deformed into engagement with the shear blade to generate the seal. The energizer may be a hard component that energizes the sealing element against the cleaned surface of the shear blade as the blade moves further relative to the seal assembly. The wiper may clean the sealing surface of the blade by removing debris from the surface prior to the energizer activating the seal.