12 CFR §160.160

1. (a)
   1. (1)Each savings association must evaluate and classify its assets on a regular basis in a manner consistent with, or reconcilable to, the asset classification system used by the OCC.
   2. (2)In connection with the examination of a savings association or its affiliates, OCC examiners may identify problem assets and classify them, if appropriate. The association must recognize such examiner classifications in its subsequent reports to the OCC.
2. (b)Based on the evaluation and classification of its assets, each savings association shall establish adequate valuation allowances or charge-offs, as appropriate, consistent with generally accepted accounting principles and the practices of the Federal banking agencies.