FULL FOOD CODE:
(A) Wall and ceiling covering materials shall be attached so that they are EASILY CLEANABLE. (B) Except in areas used only for dry storage, concrete, porous blocks, or bricks used for indoor wall construction shall be finished and SEALED to provide a SMOOTH, nonabsorbent, EASILY CLEANABLE surface.

FULL FOOD CODE:
(A) Intake and exhaust air ducts shall be cleaned and filters changed so they are not a source of contamination by dust, dirt, and other materials. (B) If vented to the outside, ventilation systems may not create a public health HAZARD or nuisance or unLAWful discharge.