Hilchos Maasei Hakarbanos 8:1

There is a stringency when it comes to an animal brought as a sin-offering that doesn’t apply to other offerings of the highest sanctity: if blood of such an animal should spill from the vessel in which it was received onto a garment before sprinkling on the altar, that garment must be washed with water in the courtyard. This is as per Leviticus 6:20: “If its blood is spilled on a garment, that on which it was spilled shall be washed in a holy place.”

Hilchos Maasei Hakarbanos 8:2

A garment of cloth, sackcloth or soft hide must be washed. A stiff hide, however, is like wood and the blood is scraped off of it. This applies to the blood of sin offerings that are eaten or burned but not to bird sin offerings, as per Leviticus 6:18: “the sin offering will be slaughtered.” We see that the Torah is discussing an offering that is killed through slaughter, not through melikah.