Śatapatha Brāhmaṇa ("of a hundred paths") 3.1.2.19

3.1.2.19

tadvā ahataṃ syāt | ayātayāmatāyai tadvai niṣpeṣṭavai brūyādyadevāsyātrāmedhyā kṛṇatti vā vayati vā tadasya medhyamasaditi yadyu ahataṃ syādadbhirabhyukṣenmedhyamasadityatho yadidaṃ snātavasyaṃ nihitamapalpūlanakṛtam bhavati teno hāpi dīkṣeta

Let it (if possible) be a new one, for the sake of unimpaired vigour. Let him (the Adhvaryu) tell (the Pratiprasthâtri) to beat it, in order that whatsoever part of it an unclean woman has spun or woven may become clean. And if it be a new one, let him sprinkle it with water, so that it become clean. Or let him be consecrated in one which is laid aside to be worn (daily) after bathing, without being soaked (in some sharp cleansing substance).