Danger from damaged fiber optic cable?

AI Thread Summary
Fiber optic cables can pose eye safety risks due to the lasers they use, particularly in FTTH systems, which may emit infrared light. The Class 1 designation indicates that the laser is safe under normal conditions, suggesting that the beam is not accessible during typical use. If a fiber optic cable is damaged, such as by biting or bending, any light that escapes is likely to scatter rather than remain in a concentrated laser form, reducing the risk of eye damage. A crack in the cable would likely result in scattered light, which is considered harmless. Overall, while caution is advised, the risk of serious injury from damaged fiber optic cables is minimal.
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Hi all,
I was not sure where to post this, so feel free to move the thread if the forum is not the most appropriate.
I was reading about safety in fiber optics and the fact that one should not be staring into a fiber optic cable to avoid eye damage. That's pretty obvious, but it also raises a few questions.

Are the lasers in FTTH (fiber to the home) single mode cables powerful enough to cause eye damage? For example my NTO box uses an infrared laser beam and a sticker on its back says: "Class 1 laser device. Laser beam when opened. Do not stare into beam". I am not sure if it means that it's class one because the beam is not accessible under normal usage, or because the laser is not powerful enough.

What would happen if the fiber optic cable was damaged. For example my cat adores biting small cables. I have protected the fiber optic one. But in case the cat bit the cable, could it damage it in such a way that the connection still works but some of the light escapes through the sheath?
Would such a leak remain in laser form and be dangerous? Or would light be scattered in all directions and therefore become harmless?

Would things change if the cable was damaged by bending it too tightly?

thanks ;)
 
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Thanks for the link, according to the article:
The odds of going blind by looking into the broken end of an optical fiber are virtually nil, since the broken surface tends to scatter the light coming through it.

My cable is not even broken in two. If anything it has a crack at some point. So I guess any leaking light would be scattered and not in laser form. Is this right?
 
I am not qualified to say - in any case my lay interpretation of the article is the same as yours, for whatever that is worth.
 
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