Most candidates lose GRID points in one of two places. They know industrial systems well but answer like an enterprise IT analyst, reaching for isolation and reimaging when the process is still running. Or they know security theory but have never had to weigh a containment decision against a turbine that cannot be stopped.

These five practice tests are designed to surface both problems while you still have time to fix them.

What is inside

430 original single-best-answer questions across five timed practice tests. No multi-select, no fill-in-the-blank, because that is not how GIAC writes this exam. Every question carries a written explanation covering why the correct answer is correct, why the most tempting wrong answer fails, and which objective area the question belongs to, so you know exactly what to go back and read.

Coverage

Questions are distributed across the seven official GRID objectives, grouped the way GIAC groups them on its own certification page:

Active defense in an ICS environment, including what Stuxnet, Industroyer, TRITON and Industroyer2 taught defenders
Detection in an ICS environment
Visibility and asset awareness, including passive discovery where scanning is prohibited
Monitoring, with real ICS protocol behavior: Modbus function codes, DNP3, OPC UA, S7comm, IEC 104, EtherNet/IP and CIP
Incident response and forensics under industrial constraints, including PLC and engineering workstation evidence
Threat hunting and analysis, including malware analysis applied to OT tooling
Threat intelligence and how to operationalize it rather than file it

Roughly a third of the questions are direct knowledge, close to half are applied scenarios where you decide the next action, and the rest ask you to interpret a log excerpt, a protocol snippet or an asset inventory and say what it shows.

How to use it

Take test one cold. Score it, read every explanation including on questions you answered correctly, and write down the objectives where you guessed. Study those, then take the next test. By test five you should be scoring consistently rather than scoring well once.

Volume 2 of this series adds five more tests and 430 more questions at the same scope and difficulty, for a second full pass closer to exam day.

Please note: this is an independently produced preparation course. It is not affiliated with, authorized by, endorsed by or sponsored by GIAC or the SANS Institute. All questions are original study material, not actual exam items. Confirm the current number of questions, time limit, passing score and permitted materials for your specific attempt in your own GIAC account before exam day.