The industry sequence used to number fibers inside a tube and tubes inside a cable: blue, orange, green, brown, slate, white, red, black, yellow, violet, rose and aqua. Fibers 13 to 24 repeat the colors with a stripe or dash. Everyone uses the same order, so in a cable with 12-fiber tubes, fiber 30 is the sixth fiber in the third tube: white in green.
Your customer is tube three, fibers seven and eight, so that's red and black in the green tube.
Rookies memorize the first six with the mnemonic Blue Orange Green Brown Slate White, then learn Red Black Yellow Violet Rose Aqua the hard way.
Also heard as
- TIA-598 color code
Related terms
Loose-tube cable
Outside plant cable whose fibers float inside gel-filled or dry tubes, protecting them from strain and temperature changes.
Ribbon cable
High-count cable in which fibers are bonded side by side into flat ribbons, usually 12 across, for mass splicing.
Splice closure
A sealed, re-enterable housing that protects fiber splices in outside plant, on poles, in vaults or buried.
Jacket
The outer plastic sheath of a fiber cable, chosen for fire rating indoors and for UV and moisture resistance outdoors.