ATP Uptime Institute Tier Classification 2

Question 1

What is the minimum availability percentage guaranteed by a Tier IV data center?

Accepted Answer

99.995%

Answer

Tier IV data centers guarantee 99.995% availability, equating to no more than 26.3 minutes of downtime per year.

Question 2

Which Tier classification requires 2N+1 redundancy for all cooling, power, and network systems?

Accepted Answer

No tier requires exactly 2N+1

Answer

No tier specifically mandates exactly 2N+1; Tier IV requires fault tolerance via multiple independent distribution paths, but the specific redundancy topology can vary.

Question 3

A data center has two independent utility feeds but only one UPS system. Which tier does this most closely describe?

Accepted Answer

Tier III

Answer

Tier III requires multiple independent distribution paths with at least N+1 redundancy on active components, but the second path need not be active simultaneously.

Question 4

What distinguishes a Tier III data center from a Tier II data center in terms of maintenance?

Accepted Answer

Tier III allows concurrent maintainability without IT load impact

Answer

Tier III's defining characteristic is concurrent maintainability — any single planned maintenance activity can be performed without impacting the IT load.

Question 5

How many distribution paths does a Tier IV facility require to be simultaneously active?

Accepted Answer

Two active

Answer

Tier IV requires two simultaneously active distribution paths, ensuring a fault in one path does not affect IT equipment.

(ATP) Accredited Tier Professional Certification (Cooling & Refrigeration) Practice Test

(ATP) Accredited Tier Professional Certification (Cooling & Refrigeration) Practice Test

ATP Uptime Institute Tier Classification 2