Exin Updated CDCS Exam Questions and Answers by kylian

In areas with frequent and extended power outages, continuous generators with at least an N+1 configuration are necessary to ensure consistent power availability. Continuous generators are designed for prolonged operation, making them suitable for scenarios where utility power is frequently unavailable, as in this case with outages exceeding 650 hours per year. An N+1 configuration ensures redundancy, which is critical for maintaining uptime in a high-availability data center.

Detailed Explanation:

Continuous generators provide reliable power over long durations, unlike standby generators, which are intended only for short-term use. The N+1 configuration ensures that there is always an additional generator available in case of failure, thus maintaining power supply even if one generator goes offline.

EPI Data Center Specialist References:

EPI best practices recommend continuous generators with redundancy for data centers located in areas with high power instability to maintain reliability and continuous operation.

Best practice is to begin raised-floor installation at the center of the room, working outward. This minimizes alignment errors and ensures the tile grid is centered, which is critical for aisle containment and rack alignment.

Starting at the perimeter (A, B, D) causes cutting of tiles along both sides, misalignment with rack rows, and possible airflow inefficiencies. By starting at the center, tiles can be cut symmetrically around the edges, providing better aesthetics, balanced airflow, and structural stability.

Industry guidelines such as CISCA recommend this approach for raised floors in mission-critical spaces.

Inert gas systems (e.g., Inergen, Argonite, Nitrogen) extinguish fire by reducing oxygen concentration, which typically requires reducing oxygen levels to ~12–15%. This means a very large volume of gas must be discharged into the room (up to 40–50% of the protected volume). Because inert gases have a low extinguishing effectiveness by weight, more total gas is required.

Halocarbon agents (FM-200, Novec 1230) extinguish fire chemically by interrupting the combustion chain reaction. They require only a small percentage (6–9%) concentration in the room volume. As a result, the storage space for cylinders is much smaller compared to inert gas systems.

Therefore, inert gas systems generally require a larger gas volume to achieve extinguishing concentrations.

Cooling airflow (CFM) can be calculated from:

Where P = IT load.

So approximately 500 CFM is required.

1,500 and 1,000 CFM are too high.

160 CFM is far too low.

Therefore, the correct answer is ~500 CFM.