# How are a refinery's emissions split between diesel, naphtha, polymers and other products?

Canonical: https://senseible.earth/answers/refinery-emissions-allocation-across-products

There is no single answer. Standards prefer splitting by process unit first, then allocating what is left by a physical measure such as mass or energy content, and only then by price. The method changes each product's figure a lot, so a supplier's number is only comparable if you know which rule it used.

## The order the standards set

1. Avoid allocation where you can: assign each process unit's fuel and process emissions to the streams it actually makes.
2. Where units make several products, split by a physical relationship such as mass or energy content.
3. Use economic value only when no physical relationship fits, and say so.

## Why it matters to a buyer

A lubricant base oil or a polymer grade can carry very different figures under mass, energy or value allocation. Two refineries quoting different numbers may simply be using different rules, not running cleaner plants.

## What to ask the supplier

- The allocation method and the boundary (gate of refinery or of the product plant).
- The year and whether captive power and steam are inside.
- Whether crude production and shipping are included upstream.

## What Senseible does here

Senseible reads the invoices for the products you buy into a dated, fingerprinted record, so a supplier figure and the quantity it applies to can be traced back to the documents behind it. It does not calculate refinery allocations.

- [Polymer resin factors](https://senseible.earth/answers/polymer-resin-emission-factors-pp-hdpe-pvc)
- [Fuel gas factor](https://senseible.earth/answers/refinery-fuel-gas-co2-factor)
- [Process flare CO2](https://senseible.earth/answers/process-flare-co2-emissions-calculation)

Sources: [ISO 14067:2018, Carbon footprint of products (iso.org)](https://www.iso.org), [GHG Protocol Product Standard](https://ghgprotocol.org/standards), [GHG Protocol Corporate Value Chain (Scope 3) Standard](https://ghgprotocol.org/corporate-value-chain-scope-3-standard)

Last reviewed 2026-10-21.