8760 is the number of hours in a year (24 hours 365 days). Dividing annual revenue by 8760 gives a basic average revenue per hour, commonly used in downtime cost calculations.

CDCP Exam Preparation Guide, page 34

EPI Data Centre Professional Course Materials

A steam canister humidifier is a type of humidifier that uses electricity to heat water in a canister containing electrodes. The water conductivity and the water level determine the amount of current and steam production. The steam canister humidifier is also known as an electrode boiler humidifier or an electrode steam humidifier123.

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 gasbased. 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. Reference: • EPI Data Centre Professional (CDCP®) Preparation Guide, page 31 • A Comprehensive Approach To Data Center Fire Safety 

Class C fires involve energized electrical equipment, such as computers, servers, switches, cables, and wiring. These fires require the use of non-conductive extinguishing agents, such as carbon dioxide, dry chemical, or clean agent, to prevent electrical shock and damage to the equipment. Water-based extinguishers ,such as Class A or K, are not suitable for Class C fires, as water can conduct electricity and cause electrocution or short circuits. Reference: EPI Data Centre Training Framework, CDCP Preparation Guide, ABCs of Fire Extinguishers

Class D fires involve combustible metals or combustible metal alloys such as magnesium, sodium and potassium. These metals can react violently with water, air, or other chemicals, and require special extinguishing agents1 Reference: 1: EPI Data Centre Professional (CDCP®) Reference Materials, page 16.