If you've worked with ship chandlers, marine purchasing agents or vessel supply orders, you've probably seen rope specified by a numeric IMPA code rather than a plain description. Buyers new to marine procurement often aren't sure what the code system actually is, or why it matters — here's the short version, and what to do with it when you're placing an order.
What IMPA actually is
IMPA — the International Marine Purchasing Association — publishes the Marine Stores Guide, a standardised catalogue of ship's stores and supplies used across the maritime industry. Every listed item, including different categories of rope and cordage, is assigned a numeric code. The idea is straightforward: a vessel's purchasing order can reference a code number instead of a written description, so the request means the same thing to a purchasing agent in one country and a supplier in another, regardless of language or local terminology.
Why buyers use the code system at all
A written description of a rope — "manila rope, 20mm, coil" — can be interpreted differently depending on who reads it and what local naming conventions they're used to. A code number strips that ambiguity out. This matters most in marine procurement because purchase orders often pass through several intermediaries — a ship's officer, a local agent, a purchasing company, and finally a supplier — before the order is fulfilled, and any one of those handoffs is a place where a written description could get garbled or mistranslated.
Important: we're not going to list specific IMPA code numbers here, because code assignments are maintained and periodically updated by IMPA itself, and republishing a number from memory risks it being wrong or outdated by the time you read it. Always check the code against your own current copy of the IMPA Marine Stores Guide, or ask your purchasing agent to confirm it, rather than relying on a number quoted secondhand.
What to send a supplier if you have an IMPA code
- The IMPA code number itself, exactly as it appears on your purchase order
- Material (manila, sisal, jute, cotton, PP/HDPE or synthetic) if the code doesn't fully specify it
- Diameter and length or coil quantity required
- Any construction requirement (twisted vs braided) if relevant to your end use
A supplier who manufactures rope directly — rather than reselling — can usually match an IMPA-coded specification against their own product range even without pulling up the code themselves, as long as you provide the material, diameter and construction alongside the code as a cross-reference.
If you don't have a code but need one
Not every buyer placing a marine rope order is working from a formal ship's supply requisition. If you need a specification that would map to an IMPA code but don't have the code itself, describe the rope by material, diameter, construction and end use instead — a direct manufacturer can confirm what they can supply without requiring the code, and your purchasing agent can look up the corresponding code separately if your process requires one on the paperwork.
Placing a marine rope order, with or without an IMPA code?
Send us the code and/or the material, diameter and quantity and we'll confirm what we can supply.