What's the proper way to vertically protect a riser in a service duct according to NFPA 13?
I have a 60m tall riser for a 15-story building.
According to NFPA, using horizontal supports on walls doesn't count for a vertical support and sway braces are a completely different thing. So, since it's an open area, riser clamps are not an option and since I have more than 60cm from the riser center to a "roofed area", I can't place hangers beyond the service duct for them to support my riser.
I thought of using vertical hangers right at the end of the service duct (2nd image), but I would need to place hangers to support at least 60m worth of system riser in just 60cm away from the riser center, which might be… weird. So I’m not sure if this is the best approach of if there’s another solution I’m not considering. So I would appreciate your help regarding this topic.
Thanks!
