If you can pass a load-shed order in the middle of a cascading event without a repeat-back, you're going to fail more than the exam. COM-002 is the standard that turns operator language into a reliability tool — and it shows up on the NERC Reliability Coordinator exam every single sitting. Expect it in scenario questions, definitions, and "what does the Balancing Authority do next" traps.
Why COM-002 Matters
COM-002 (Operating Personnel Communications Protocols) exists because sloppy communication has directly contributed to major disturbances on the Bulk Electric System. The standard forces a specific, verifiable exchange whenever a Reliability Coordinator, Balancing Authority, or Transmission Operator issues an operating instruction — and it draws a hard line around one particular kind of instruction: the Reliability Directive.
Test Tips
- Know the definition of a Reliability Directive cold. Per the NERC Glossary, it's a communication initiated by a Reliability Coordinator, Balancing Authority, or Transmission Operator where action by the recipient is necessary to address an actual or expected Emergency or Adverse Reliability Impact. If the scenario says "prevent an IROL exceedance" or "mitigate an actual Emergency," that's a Reliability Directive — full three-part communication is mandatory.
- Three-part communication is issue → repeat back → confirm. The issuer states the instruction, the recipient repeats it back (not paraphrases it), and the issuer confirms it was correct or restates if it wasn't. Exam distractors love "acknowledged" or "copy that" — those don't satisfy COM-002.
- COM-002 applies only to operating instructions, not general conversation. If the question describes a status update, weather chat, or a request for information, three-part communication isn't required. The trigger is an instruction to take (or not take) an action affecting the BES.
- Reliability Directives get identified as such. The issuer must identify the communication as a Reliability Directive when issued. If a scenario shows the RC saying "shed 300 MW in Zone 4 — this is a Reliability Directive," that phrasing is deliberate and testable.
- Recipient must repeat back a Reliability Directive. For a Reliability Directive specifically, the recipient is required to repeat back the directive. If they don't, the issuer must take action to ensure the directive is understood. Silence is not compliance.
- Written / logged, not just spoken. Reliability Directives get logged. Expect exam questions asking what record-keeping is required — the issuing entity keeps a log sufficient to reconstruct the directive.
5 Practice Questions
- A Reliability Coordinator contacts a Transmission Operator and states: "Open breaker 2145 at Riverton Substation to relieve loading on the 345 kV line — this is a Reliability Directive." Under COM-002, what is the Transmission Operator required to do FIRST?
- A. Log the directive and take the action
- B. Acknowledge with "copy" and open the breaker
- C. Repeat the directive back to the Reliability Coordinator
- D. Notify the Balancing Authority before acting
- Which of the following communications MUST be issued using three-part communication under COM-002?
- A. A weather advisory shared between control rooms
- B. An operating instruction issued by a Balancing Authority to a Generator Operator
- C. A shift turnover between two operators at the same entity
- D. A request for the current MVAR output of a unit
- Per the NERC Glossary, a Reliability Directive is a communication issued to address:
- A. Any deviation from the day-ahead operating plan
- B. An actual or expected Emergency or Adverse Reliability Impact
- C. A market-related redispatch request
- D. Any communication between a BA and its RC
- A Reliability Coordinator issues a Reliability Directive over the phone. The recipient does not repeat the directive back. What is the RC required to do under COM-002?
- A. Assume the directive was received and move on
- B. Log the failure and continue with the next task
- C. Take action to ensure the directive was understood by the recipient
- D. Escalate to the recipient's supervisor before taking further action
- Which statement about COM-002 is TRUE?
- A. Three-part communication is only required during declared Emergencies
- B. Only Reliability Coordinators may issue operating instructions
- C. The issuer of a Reliability Directive must identify the communication as such when issued
- D. Paraphrasing a Reliability Directive back to the issuer satisfies the repeat-back requirement
Answer Key & Explanations
- C. Under COM-002, when a Reliability Directive is issued, the recipient must repeat the directive back to the issuer before acting, so the issuer can confirm the instruction was correctly received. Logging and action come after the repeat-back.
- B. COM-002 applies to operating instructions issued by an RC, BA, or TOP directing another entity to take (or not take) an action affecting the BES. A weather advisory, a shift turnover, and a request for information are not operating instructions.
- B. The NERC Glossary defines a Reliability Directive as a communication initiated by an RC, BA, or TOP where action by the recipient is necessary to address an actual or expected Emergency or Adverse Reliability Impact.
- C. If the recipient fails to repeat back a Reliability Directive, the issuer is required to take action to ensure the directive was understood by the recipient. The RC cannot simply assume receipt.
- C. The issuer of a Reliability Directive is required to identify the communication as a Reliability Directive when it is issued. Three-part communication is required for operating instructions generally, not only during declared Emergencies, and BAs and TOPs may also issue operating instructions. A repeat-back must be verbatim enough for the issuer to confirm — paraphrasing does not satisfy the standard.
Bottom Line
COM-002 is a high-yield exam standard because it's binary: either you followed the protocol or you didn't. Master the Reliability Directive definition, the three-part sequence, and the issuer's obligation when the recipient doesn't repeat back — you'll pick off these questions cleanly on the RC exam and, more importantly, run cleaner comms in the control room.
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