Understanding Fiber Optic Cable Color Codes

Fiber optic cables come in a variety of colors, and these colors aren't just for aesthetics – they actually indicate the type of fiber inside the cable. 

This color coding system helps technicians identify the cable's properties quickly and easily.

What Do different fiber strand colors represent?

@lanshack Do you know what these different colors represent? #fiberoptics #fiberoptic #foryou #viral ♬ original sound - LANshack

• Singlemode Fiber (Yellow): Designed for longer distances and higher bandwidth applications.

• Multimode Fiber (Orange, Aqua, Green): Used for shorter distances and lower bandwidth applications. Here's a breakdown of some common multimode fiber colors:

• Orange: Traditionally used for OM1 fiber.  These are less likely to be used in newer installations in favor of OM3 and OM4. 

• Yellow: OM2(62.5/125µm fiber.  OM2 is not used by most professionals.

• Aqua: Often indicates OM3 (50/125µm) and OM4 fiber, a popular choice for multimode applications.

• Green: May represent OM5 (50/125µm) fiber, the latest standard for multimode fiber.

Note: While these are common color associations, it's important to consult the cable manufacturer's specifications for definitive identification

Here’s a graphic from FOA to further showcase the difference colors and their fiber types.

What happens when you mix them up?

While some fiber types with similar core diameters (like OM3, OM4, and OM5) can be coupled in a pinch, it's generally not recommended. Mixing different fiber types can lead to performance issues and is not considered industry standard.

The reason you may have issues comes down to loss of data, or attenuation.

For optimal performance and reliability, it's best to use cables with the correct fiber type for your specific application.

If you need to connect OM1 to OM3, for example, you’ll want to make sure you have the right coupler.

While it might seem okay for shorter distances to use OM3 as an extension of your network, there will be a small light refraction issue, which can lead to a loss of data you wouldn’t have if you used OM3 to OM3 for your connection.

If you haven’t seen losses in your data or performance issues, then it’s possible that you just aren’t passing too much data so the loss is too small to notice.  If you’re passing a ton of data, that’s where it gets tricky.

The biggest thing to consider is not mixing singlemode (9/125) and OM1 (62.5/125) as the dimensions are way off.

Do the United States and Europe have different jacket colors?

While the above-mentioned OM1-OM5 and SM cables have specific colors, you may have seen something different if you’re in another country than the United States.  

There is a different color code methodology which adds another layer of complexity to your installations.

What does OM in OM1 stand for? And why doesn’t singlemode have an OM rating?

The O stands for "optical" and the M stands for "multimode.”  S is the abbreviation for "singlmode.” 

Multimode has OM1,2,3,4,and5 while singlemode has OS1 and OS2.