US buyers sourcing MPO trunks or patch cords from India should specify the NEC Article 770 listing the installation needs (OFNP for plenum air spaces, OFNR for risers, OFN for general use), the TIA-568.3-D polarity method, fibre type and lengths. Radix Fibrotech quotes export orders from Pune; ask for test reports and the origin documents your customs broker needs.
NEC listings US specifiers write into fibre specs
Inside US buildings, optical fibre cable falls under Article 770 of the National Electrical Code (NFPA 70), which states and cities adopt into local law. The code groups cables by listing, the listing is printed on the jacket, and the electrical inspector reads the jacket print rather than the datasheet. A US buyer sourcing MPO trunks or patch cords from India should therefore open the specification with the listing.
| Listing | Meaning | Where it may be installed | Fire test behind the listing |
|---|---|---|---|
| OFNP | Optical fibre, nonconductive, plenum | Air-handling spaces such as ceiling plenums, plus every location below | NFPA 262 (formerly UL 910) |
| OFNR | Optical fibre, nonconductive, riser | Vertical runs between floors, plus general-purpose locations | UL 1666 riser shaft test |
| OFN or OFNG | Optical fibre, nonconductive, general purpose | Within one floor, outside risers and plenums | Vertical tray flame test |
| OFCP, OFCR, OFCG | Conductive versions with a metallic member or armour | Same spaces as the matching nonconductive type | Same test as the matching type |
A higher listing may replace a lower one: OFNP can go anywhere OFNR is permitted, and OFNR can stand in for OFN. An LSZH jacket is a material choice, not an NEC listing, so a halogen-free cable is not plenum rated unless it carries the OFNP mark. Metallic armour makes a cable a conductive type in NEC terms, which brings bonding and grounding duties; say in the RFQ if you want armoured fibre optic cables with non-metallic armour instead.
Polarity and connector standards in US data centres
US data centre drawings usually cite ANSI/TIA-568.3-D for optical cabling components. It defines the three MPO polarity methods (A, B and C) along with the colour code for connectors and adapters. The MPO interface itself is described in TIA-604-5, also known as FOCIS 5, and data centre topology follows ANSI/TIA-942. Mark the polarity method and the pinned or unpinned end on the drawing; the guide to MPO polarity types A, B and C shows how each method maps fibre positions from one end to the other.
Operators building for 400G and 800G Ethernet increasingly order 8-fibre and 16-fibre MPO links alongside the familiar 12-fibre and 24-fibre layouts. Confirm the fibre count per connector before you ask for MTP/MPO trunk cables, because a 12-fibre trunk feeding an 8-fibre optic leaves four fibres unused in every link.
Where US demand for these assemblies comes from
Hyperscale and colocation data centres account for most MPO trunk and cassette volume, with the largest single cluster in northern Virginia. Broadcast and live sport crews use SMPTE hybrid camera cable and tactical reels that are deployed and recovered for each event. Defence and aerospace programmes order rugged connectors and expanded beam terminations to drawings that often cite US military specifications; quote those references in full so the supplier can say what it can and cannot match. Oil, gas, pipeline and utility operators buy outdoor assemblies with UV-resistant jackets and armour against rodents.
Paperwork, duties and trade terms for imports from India
A typical US import file for fibre assemblies holds a commercial invoice showing value, origin and a suggested HTS code, a packing list with carton weights and dimensions, a certificate of origin, the air waybill or ocean bill of lading, and the test reports for the lot. Fibre assemblies can fall under heading 8544 or 9001 depending on construction, so let your licensed customs broker confirm the full HTS code before the order is placed. Ocean shipments also need an Importer Security Filing, which your broker lodges using data the supplier provides before loading.
Duty rates on goods of Indian origin have changed several times since 2025, so ask your broker for a current landed-cost estimate when comparing suppliers. Federal contracts can carry country-of-origin rules under the Trade Agreements Act or Buy American requirements; check whether Indian-origin products are acceptable under your contract before requesting a quote.
Radix quotes export orders from Pune. Agree the Incoterms 2020 rule in the quote: FCA Pune suits buyers who already use a freight forwarder, CIP or DAP to a named US city moves the main carriage to the seller, and DDP would make the seller the US importer of record, which a manufacturer outside the US is rarely set up to do.
Call times between Pune and US offices
India Standard Time is UTC+5:30 with no daylight saving. Radix works 09:00 to 18:00 IST, Monday to Friday, and that day ends at 07:30 in New York during winter and 08:30 during US daylight saving time. On the West Coast it ends before dawn. Plan on email for drawings and technical questions, and book any live call for the early US Eastern morning.
What a US RFQ for MPO trunks should state
- The NEC listing of the bulk cable (OFNP, OFNR or OFN) and whether any armour must be non-metallic.
- Fibre type: OM3, OM4, OM5 or OS2, with the jacket colour you expect.
- Fibre count, connector type and gender at each end, and the TIA-568.3-D polarity method.
- Length with its unit. If the drawing is in feet, say whether a metric conversion may be rounded and which way.
- Maximum insertion loss per connector or per link, and the test reports you need with each lot.
- Quantity, labelling scheme, packaging, delivery address and Incoterm.
The RFQ guide for fibre assemblies explains each line in more detail. Send the drawing and quantities through the request a quote form and ask for loss values, packing details and evidence of the cable listing in the reply.
Questions buyers ask
Can an LSZH fibre cable go in a US plenum space?
Only if the cable is listed OFNP and carries that marking on the jacket. Low smoke zero halogen describes the sheath compound, while the NEC listing records how the finished cable performed in a fire test. Ask for the listing by name.
Who holds the UL listing on a fibre patch cord or trunk?
The listing belongs to the bulk cable and is held by its manufacturer, whose mark appears on the jacket. Ask the assembly supplier to name the cable it will use and to send a photo of the jacket print with the sample.
Which Incoterm works best for a first order from India?
Buyers with an established forwarder usually ask for FCA Pune, which keeps freight and US customs on their side. Buyers without one often prefer CIP or DAP to their own city. Write the Incoterms 2020 rule and named place in the purchase order.
Should lengths on a US drawing be in feet or metres?
Either works if the unit is explicit. State which unit governs, the tolerance, and whether length is measured end face to end face, because mixed units on one drawing often produce wrong lengths.
Is there a US duty on fibre assemblies made in India?
Duty depends on the HTS code and on the rates in force for Indian-origin goods on the date of entry. Those rates have moved since 2025, so get a current figure from your customs broker.