---
id: KB-IU-012
url: https://app.codecontract.io/help/manufacturing/plastics-converters-and-recycled-content
idioma: en
categoria: sector-industria
subcategoria: plasticos
audiencia: usuario
nivel: avanzado
actualizado: 2026-08-13
tambienEn: [es]
relacionados: [KB-NO-002, KB-IU-009]
citadoPor: [KB-IU-020]
---

# Plastics converters and recycled content

_Claiming a recycled percentage is easy; supporting it with documentation is not._

**Responde a:** recycled content documentation · food contact declaration for plastics · changing resin supplier · evidencing recycled content

A converter lives between two demands pulling in different directions: customers want more recycled material, and at the same time want the product to keep meeting the same requirements. On paper, those two things rest on different documents and neither covers the other.

## The three declarations that are not interchangeable

| Declaration | What it asserts | What supports it |
| --- | --- | --- |
| Composition and performance | What the material is and how it behaves | Your resin supplier, per reference |
| Suitability for use | That it fits the intended application | Your supplier and, depending on use, you |
| Recycled content | What proportion comes from recovered material | Your intake traceability, not a promise |

> [!IMPORTANT]
> The third is the most asserted and the worst supported. A recycled percentage **is not a product characteristic: it is the result of a balance between what came in and what went out**. If you cannot reconstruct which material went into which production run, the figure you give is an estimate — and the moment a customer audits it, that distinction shows.

## What you must be able to show

1. **What material came in, from whom and with what documentation** — Including recovered material, which arrives with the poorest paperwork.
2. **What was produced from what** — The link between intakes and outgoing batches, as in any traceability.
3. **The criterion used to calculate the percentage** — Written once and applied identically: varying it between customers gets detected.
4. **And what happens when the supplier changes** — Another resin is another reference, and it drags new declarations with it.

> [!WARNING]
> The point that surprises on a supplier change: even with equivalent material, **declarations follow the reference and are not inherited**. Switching resin on price or availability is a purchasing decision that drags technical documentation, and if nobody tells whoever maintains the declarations, your finished product quietly loses its backing with nothing visible changing.

## When the end use is sensitive

**En corto**

- Food contact, medical or children's uses add their own requirements to material and process.
- And recovered material in those uses has specific conditions that do not apply to any origin.
- That is not settled by the resin supplier's declaration: check it before accepting the order.

> [!NOTE]
> Which frameworks apply to each use, what may be declared and with what backing depends on the product, the destination and the market, and it gets updated. **Before committing to a percentage or a use in an order, confirm with your adviser or the resin manufacturer**; this only explains what documentation exists and what each asserts.

**Does the supplier's declaration support the percentage?**

It supports what they supplied, not the balance of your production.

**What if we blend batches of different origin?**

Then the calculation criterion is what must be written down and applied consistently.

**How long must it be kept?**

Whatever the end use requires, with margin: in packaging, longer than the life of the product it holds.

## Ejemplos

**A converter offers a recycled percentage and a customer asks to audit it.**

- Reconstructs the balance from intakes and outgoing batches
- Writes down the calculation criterion and applies it uniformly

→ It can sustain the figure in the audit instead of admitting it was an estimate.

**The recycled content is declared with no backing.**

- Stores what backs it with the reference

→ The declaration holds up.

**The supplier changes the blend and nobody knows.**

- Asks them to communicate any change

→ The change arrives before the question.

**A client asks you to evidence one specific run.**

- Checks that production run's file

→ You answer per run.

**Intakes from different suppliers get mixed.**

- Records what went into each run

→ You can say what came from where.

**The supplier's documentation expires.**

- Records expiries per supplier

→ The warning arrives before producing.