Because of these high temperatures, the adhesive would dissolve and the silicone profile of your chastity belt would drop. The best way to clean every product is with running lukewarm water. Also you can use ph-neutral liquid soap, so the profiles and adhesive won’t be affected and dissolved.
To remove persistent stains, like code radicals or urine residues, soak in the chastity belt for some time, so that the deposits get time to dissolve slowly.
Hygiene is most importantly, especially when wearing the chastity belt a period of time or if used as a long-term carrier.