Leviticus 15:22-25

²²Anyone who touches what she was sitting on has to wash their clothes, and wash themselves with water, and they will be unclean until the evening.

²³Whether it's a bed or something she was sitting on, anyone who touches it will be unclean until the evening.

²⁴If a man sleeps with her and the blood from her period touches him, he will be unclean for seven days, and any bed he lies on will be unclean.

²⁵When a woman has a discharge of blood for several days when it's not the time for her period, or if it continues past her period, she will be unclean for the whole time she is bleeding, not just for the days of her period.