What does the expression SL-T (BPCS Zone) vector {2 2 0 1 3 1 3}...

The SL-T (BPCS Zone) vector {2 2 0 1 3 1 3} represents the Target Security Level (SL-T) across each of the seven Foundational Requirements (FRs) in ISA/IEC 62443-3-3.

Each number in the vector corresponds to a security level (0–4) assigned to a particular FR, as follows:

FR1 – Identification & Authentication Control (IAC): 2

FR2 – Use Control (UC): 2

FR3 – System Integrity (SI): 0

FR4 – Data Confidentiality (DC): 1

FR5 – Restricted Data Flow (RDF): 3

FR6 – Timely Response to Events (TRE): 1

FR7 – Resource Availability (RA): 3

“Security levels are represented as vectors of seven values, each corresponding to the target security level for a foundational requirement (FR).”

— ISA/IEC 62443-3-3:2013, Annex A – SL Vector Format

This allows zone-specific tailoring based on risk — some FRs may require SL 3, others SL 0, depending on system criticality and exposure.