# How does a Trichy boiler parts fabricator count the steel plate and tube it buys?

Canonical: https://senseible.earth/answers/trichy-boiler-fabricator-steel-plate-scope-3

As Scope 3 category 1, purchased goods: tonnes of plate and tube times a supplier-specific factor, or a route average if none is given. Your own Scope 1 covers stress relieving furnaces and cutting gases; welding power is Scope 2.

## Purchased steel

1. Total tonnes of plate, tube and sections bought, from invoices.
2. A factor per tonne from each mill, or a published route average.
3. Multiply and add up by supplier.

## Your own sources

- Fuel for stress relieving and heat treatment furnaces.
- LPG and other gases for cutting and preheating.
- Electricity for welding and machining, as Scope 2.

## When a customer asks for a product figure

Share the steel by the weight that goes into each job, add your process emissions per job, and allow for offcuts that are sold as scrap.

## What Senseible does here

Senseible reads supplier invoices into dated, fingerprinted records, so each purchased material in a Scope 3 figure traces back to its document.

- [Purchased stainless steel factor](https://senseible.earth/answers/emission-factor-for-purchased-stainless-steel)
- [Primary data share meaning](https://senseible.earth/answers/primary-data-share-meaning)
- [Welding electrode carbon per kg](https://senseible.earth/answers/welding-electrode-carbon-footprint-per-kg)

Sources: [GHG Protocol Corporate Value Chain (Scope 3) Standard](https://ghgprotocol.org/corporate-value-chain-scope-3-standard), [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard), [worldsteel](https://worldsteel.org)

Last reviewed 2026-10-22.