Pass the Exin EPI Data Centre CDCP Questions and answers with ExamsMirror

Availability is the degree to which a system, product or component is operational and accessible when required for use. It is one of the attributes of reliability, which is the ability of a system or component to perform its required functions under stated conditions for a specified period of time. Availability can be calculated as the ratio of the expected value of the uptime (the time when the system is functional) to the total time (uptime plus downtime) of a system or component. Availability can also be influenced by factors such as maintainability, fault tolerance, redundancy, diagnostics, and logistics.

The objective of data center fire protection is to suppress or extinguish a fire before it can cause significant damage to the equipment, personnel, or business continuity. Fire suppression systems are designed to reduce the heat, oxygen, or fuel elements of the fire triangle, and to limit the spread of fire and smoke. Fire suppression systems can be classified into two types: water-based and gas-based. Water-based systems include sprinklers, mist, and water spray systems, which use water as the extinguishing agent. Gas-based systems include inert gas, halocarbon, and clean agent systems, which use gases or chemicals as the extinguishing agent. The choice of fire suppression system depends on several factors, such as the fire risk, the type of fuel, the environmental impact, the reliability, the cost, and the compatibility with the data center equipment and operations.

Mean time between failures (MTBF) is a measure of the reliability of a system or component. It represents the average time that a system or component will operate before it fails. The higher the MTBF, the more reliable the system or component is. MTBF is calculated by dividing the total time of operation by the number of failures that occur during that time. MTBF is used to compare the reliability of similar systems or components, and to help with maintenance planning, inventory management, and system design.

High relative humidity in a data center can lead to corrosion of metal parts and electronic contacts, potentially causing failures. Electrostatic discharge is a risk with low humidity, not high.

Cost of downtime is the total amount of money lost due to a data centre outage or disruption. It can be classified into two categories: direct and indirect. Direct costs are the immediate and measurable expenses incurred during or after an outage, such as lost revenue, lost productivity, recovery costs, compensation costs, penalties, etc. Indirect costs are the long-term and intangible impacts of an outage, such as reputation damage, customer dissatisfaction, loss of market share, legal liabilities, etc. Both direct and indirect costs can vary depending on the type, duration, and severity of the outage, as well as the industry, size, and location of the data centre.

According to the CDCP® Preparation Guide, an audible signaling and notification device is a device that produces a sound to alert or notify the occupants of a data center of an event or condition. Sirens are examples of such devices, as they can emit loud and distinctive tones to warn of fire, emergency, or security incidents. Strobes, on the other hand, are visual signaling and notification devices that produce flashes of light to attract attention or convey information. Alarms and clocks are not specific types of devices, but rather general terms that can refer to various audible or visual devices.

The last stage in stages of combustion is flaming fire, which occurs when the fuel vapors and oxygen are mixed in the right proportion and ignited by a flame or a spark. Flaming fire is characterized by visible flames, intense heat, and rapid oxidation. Flaming fire can cause severe damage to the data center equipment, personnel, and business continuity. Therefore, it is important to prevent or suppress flaming fire as soon as possible using appropriate fire detection and suppression systems.

The four main components of a refrigeration circuit are the evaporator, the compressor, the condenser, and the expansion valve, according to the CDCP Preparation Guide1 and various web sources234. A refrigeration circuit is a system that transfers heat from a low-temperature region to a high-temperature region, using a working fluid called refrigerant. The refrigeration circuit operates in a closed loop, where the refrigerant changes its state from liquid to vapor and back to liquid, while absorbing and releasing heat. The four main components of the refrigeration circuit perform the following functions:

•The evaporator is a heat exchanger that absorbs heat from the low-temperature region, such as the data centre room, and transfers it to the refrigerant. The refrigerant enters the evaporator as a low-pressure, low-temperature liquid, and leaves the evaporator as a low-pressure, low-temperature vapor.

•The compressor is a mechanical device that increases the pressure and temperature of the refrigerant vapor. The refrigerant enters the compressor as a low-pressure, low-temperature vapor, and leaves the compressor as a high-pressure, high-temperature vapor.

•The condenser is another heat exchanger that releases heat from the refrigerant to the high-temperature region, such as the outside air or water. The refrigerant enters the condenser as a high-pressure, high-temperature vapor, and leaves the condenser as a high-pressure, low-temperature liquid.

•The expansion valve is a device that reduces the pressure and temperature of the refrigerant liquid. The refrigerant enters the expansion valve as a high-pressure, low-temperature liquid, and leaves the expansion valve as a low-pressure, low-temperature liquid. The expansion valve also controls the flow of the refrigerant into the evaporator, depending on the cooling load.

The minimum clearance space required below water sprinkler heads and nozzles of gas-based fire suppression systems is 46 cm / 18 inches, according to the CDCP Preparation Guide1 and OSHA regulation 29 CFR 1910.159 © (10)2. This clearance space is necessary to ensure that the sprinkler spray or gas discharge can reach the fire and cover the protected area effectively. Any material or obstruction below this clearance space can interfere with the sprinkler or gas distribution and reduce the fire suppression performance. Therefore, building owners and managers should ensure that all storage and objects in the data centre are kept below this clearance space, and that the clearance space is maintained at all times.

FM200 (HFC-227) is a clean agent fire suppression system that uses a high-pressure gas to extinguish fires by reducing the oxygen concentration and absorbing the heat. FM200 is stored in cylinders at pressures of up to 42 bar (600 psi) and is released through nozzles into the protected area. Because of the high pressure, the nozzles must be mounted with two brackets to prevent them from moving or breaking during discharge. The brackets must be securely attached to the ceiling or wall and aligned with the nozzle outlet. The nozzle outlet must also be free of any obstructions that could affect the discharge pattern or distribution.