Color of fiber optic cable protective tube

Fiber optic protection tube colors indicate the type of fiber inside, with yellow for single-mode, orange for multimode, and blue for polarization-maintaining fibers.

Standard Color Coding

Fiber optic protection tubes, also known as furcation tubing, are color-coded to help technicians quickly identify the type of fiber and ensure proper handling:

• Yellow: Single-mode fiber (OS1/OS2), typically with a 9µm core for long-distance, high-speed transmission using laser sources .
• Orange: Multimode fiber (OM1/OM2), commonly used for shorter-distance applications with LED or laser sources .
• Aqua: Laser-optimized multimode fiber (OM3/OM4), often used in high-speed data centers .
• Blue: Polarization-maintaining fiber, used in specialized applications requiring stable polarization .
• Black: Provides light-blocking protection to prevent visible light from entering the fiber . Custom colors are sometimes used for organizational purposes or to differentiate fibers in high-density cables, but the above colors follow industry standards like TIA-598-C .

Additional Considerations

• Tube Material: Furcation tubing can be made from polyvinylidene fluoride (PVDF) for rigidity or placed inside stainless steel sleeves for extra protection against bending, dust, and environmental stress .
• Inner Diameter: The tubing's inner diameter must be slightly larger than the fiber's outer diameter to avoid stress or damage .
• High-Fiber Count Cables: For cables with more than 12 fibers, the color sequence repeats with stripes to maintain unique identification for each fiber group .
• Environmental Protection: Protection tubes also shield fibers from moisture, UV, temperature changes, and mechanical stress, ensuring long-term reliability .

Summary

Using the correct color-coded protection tube is essential for fiber identification, safe installation, and compliance with standards. Yellow indicates single-mode, orange for multimode, blue for polarization-maintaining, and black for light-blocking. For high-density or specialized applications, additional color variations or stripes may be used to maintain clarity and prevent miswiring .