Just read about a new fiber optic bend radius rule that caught me off guard

I was scrolling through some industry updates last night and saw something about the new NEC code taking effect next month. They're apparently tightening the minimum bend radius for fiber cables in residential drops. I've been doing the same bends for 5 years without issues, but this could mean rethinking how we route around tight corners in attics. Is anyone else prepping for this or is it just another paper change that nobody enforces?

3 comments

3 Comments

kellyjones2mo ago

yeah i actually ran into this last week on a new build. the inspector flagged a bend i did that was totally fine per the old spec but now it's too tight. what i started doing is using those pre-formed corner guides that have a built in radius, they're cheap and save you from having to re-pull later. if you're routing in attics try to give yourself an extra inch or two of slack before hitting the tight spots so you can loop it a little wider. honestly most inspectors are gonna check the obvious spots like the service entrance and any wall transitions but if they're in a bad mood they'll measure everything.

wells.olivia2mo ago

too tight per the old spec" actually just means it was always wrong, they're finally enforcing it now.

noahmartin2mo ago

That 8 inch radius spec on 2 inch conduit caught me off guard last month. I used to think "too tight per the old spec" was just inspectors being picky, but @wells.olivia calling it "always wrong" actually makes a lot of sense now that I look back at some of my older pulls. I had one run where a 90 was just barely within the old limits and after a few years the wire was already showing signs of stress at that spot. Now I just use the pre-bent sweeps and give myself that extra foot before any tight spot like kellyjones said, it saves the headache of having to redo it later.