46 C.F.R. § 111.40-11 – Numbered switching unit and panelboard directory.

(a) Each panelboard switching unit must be numbered.
(b) Each panelboard must have:
1. (1) A circuit directory cardholder; and
2. (2) A circuit directory that has:
  1. (i) The circuit designation of each circuit;
  2. (ii) A description of the load of each circuit; and
  3. (iii) The rating or setting of the overcurrent protective device for each circuit.