Numbers 19:9, 18

“A man who is clean shall gather up the ashes of the heifer and put them in a ceremonially clean place outside the camp. They are to be kept by the Israelite community for use in the water of cleansing; it is for purification from sin.

Then a man who is ceremonially clean is to take some hyssop, dip it in the water and sprinkle the tent and all the furnishings and the people who were there. He must also sprinkle anyone who has touched a human bone or a grave or anyone who has been killed or anyone who has died a natural death.