Numbers 19:6

19:6 And the priest must take cedar wood, hyssop, and scarlet wool and throw them into the midst of the fire where the heifer is burning.

Numbers 19:19

19:19 And the clean person must sprinkle the unclean on the third day and on the seventh day; and on the seventh day he must purify him, and then he must wash his clothes, and bathe in water, and he will be clean in the evening.