PDFWAC 16-403-184
Invisible water core.
Invisible water core will be considered as "damage" when existing around the core and extending to water core in the vascular bundles, or surrounding the vascular bundles when the affected areas surrounding three or more vascular bundles meet or coalesce, or existing in more than a slight degree outside the circular area formed by the vascular bundles: Provided, that invisible water core shall not be scored as damage against the Fuji variety of apples under any circumstances.