Numbers 19:7-10

19:7 Then the priest must wash his clothes and bathe himself in water, and afterward he may come into the camp, but the priest will be ceremonially unclean until evening. 19:8 The one who burns it must wash his clothes in water and bathe himself in water. He will be ceremonially unclean until evening.

19:9 “‘Then a man who is ceremonially clean must gather up the ashes of the red heifer and put them in a ceremonially clean place outside the camp. They must be kept for the community of the Israelites for use in the water of purification – it is a purification for sin. 19:10 The one who gathers the ashes of the heifer must wash his clothes and be ceremonially unclean until evening. This will be a permanent ordinance both for the Israelites and the resident foreigner who lives among them.

Numbers 19:21-22

19:21 “‘So this will be a perpetual ordinance for them: The one who sprinkles the water of purification must wash his clothes, and the one who touches the water of purification will be unclean until evening. 19:22 And whatever the unclean person touches will be unclean, and the person who touches it will be unclean until evening.’”