California Code, Health and Safety Code - HSC § 7010.5

“Residue” means human ashes, bone fragments, prostheses, and disintegrated material from the chamber itself, imbedded in cracks and uneven spaces of a cremation chamber, that cannot be removed through reasonable manual contact with sweeping or scraping equipment. Material left in the cremation chamber, after the completion of a cremation, that can be reasonably removed shall not be considered “residue.”