Sprinkler or automatic spray nozzles being used in a commercial type cooking equipment ducts, duct collars, and plenum areas shall have an orifice with K-factor not less than

• A. 0.8
• B. 1.0
• C. 1.4
• D. 2.0

Answer: (C)

The key idea is that the K-factor of a sprinkler nozzle determines how much water it delivers at a given pressure—the higher the K-factor, the more flow you get. In commercial cooking equipment ducts, duct collars, and plenums, a grease-laden fire can develop quickly, so a larger discharge is needed to control it. That’s why the standard specifies a minimum K-factor of 1.4 for these nozzles. Therefore, the orifice must have a K-factor not less than 1.4. Among the choices, 1.4 is the minimum acceptable value; smaller K-factors would not meet the requirement, while a value like 2.0 would also satisfy the condition but isn’t the minimum.