Flexible sprinkler drop

[SprinkGuy23]

Does anyone know of any clarification of NFPA 13 2019 edition 17.4.1.3.3.3?

"17.4.1.3.3.3* Where flexible sprinkler hose fittings exceed 6 ft(1.8 m) in length and are supported by a suspended ceiling in
accordance with 17.4.1.3.3.2, a hanger(s) attached to the structure shall be required to ensure that the maximum unsupported length does not exceed 6 ft (1.8 m)."

Is this referring to only the flexible hose itself or would the armover be added. For example, a 6' flexible drop is connected to a 10" armover. Would the 10" armover need to be hung due to the assembly being longer than 6'?

 

[UFT12]

Common sense should prevail. Flexible hose and rigid pipe have different properties and behave differently. Each one has its own limitation for unsupported free length. In your example you present the two within the limits to be unsupported but personally I wouldn't let it like that. The limitation of 6 ft/1.8 m of NFPA 13 is meant mainly for a hose that is directly tied to the branch line. For your example, I would include a support. This support however can potentially be right at the end of the rigid pipe, satisfying practically the 6 ft/1.8 m limit for the hose.

 

[SprinklerDesigner2]

I agree with UFT12.