NERC entities must comply with three physical security standards:
On order from FERC, NERC is currently developing physical security standards to apply to some substations and control centers; these standards will probably come into effect in 2014.
CIP-003 Requirement 2 of Version 5 requires a policy for physical security controls for Low impact Bulk Electric System (BES) assets. NERC is currently developing specific requirements for these policies, per FERC's directive in Order 791.
CIP-006 Version 5 requires physical protection of control systems at High and Medium impact BES assets, with a compliance date of April 1, 2016.
Webinar PSF 6-11-14