Carbon and LCA glossary

Published on 07/09/2026

The twenty terms that come up as soon as a client asks for a carbon footprint. Each definition stands on its own: it does not refer back to the previous one and assumes nothing.

LCA, life cycle assessment

A method that measures a product's environmental impact across its whole life, from material extraction to end of use. It follows a standardised framework, splits the product into stages, and assigns to each the incoming and outgoing flows. A full LCA measures several indicators; when it measures only one, climate, the result is better called a product carbon footprint.

PCF, product carbon footprint

The result of an assessment restricted to climate change alone, expressed in kilograms of CO₂ equivalent per functional unit. It is the figure a house asks its supplier for on a given part. It says nothing about water, toxicity or land use: a product can improve its PCF while degrading another indicator.

Scope 1

An organisation's direct emissions: what burns on its sites and in its vehicles, plus refrigerant leaks. It is the share it controls most directly, and usually the smallest one in watchmaking.

Scope 2

Emissions from purchased and consumed energy: electricity, heat, steam, cooling. They do not come out of the company's chimneys but out of its energy supplier's. The electricity mix of the producing country therefore weighs heavily on the result.

Scope 3

The fifteen value chain emission categories, upstream and downstream: purchases, transport, waste, travel, use of sold products, end of life. It is almost always the dominant part of an inventory, and the only one the company does not measure directly.

Scope 3.1, purchased goods and services

The first of the fifteen scope 3 categories: the footprint of everything the company buys. In watchmaking it dominates a house's inventory, because most of the value is made outside. It is calculated either from real supplier data or, for want of better, by multiplying a purchase amount by a sector ratio.

Emission factor

A coefficient that converts a physical quantity into emissions: so many kilograms of CO₂ equivalent per kilogram of steel, per kilowatt-hour, or per tonne-kilometre transported. It comes from a reference database, carries a location and a date, and its choice often explains the gap between two results better than the difference between the two products.

Primary data

A measurement from where the emission occurs: a workshop electricity bill, a meter reading, an LCA produced by the part's manufacturer. It moves when the process changes, which is exactly what is expected of a steering indicator.

Secondary data

A value taken from a generic database or a sector average, for lack of one's own measurement. It makes it possible to produce a figure where there would otherwise be none, but it responds to no effort: two very different workshops get the same result if they use the same average.

Spend-based ratio

A factor expressed per unit of spending, converting a purchase amount into emissions. It is the last resort when no physical data exists. Its flaw disqualifies it for steering: the figure falls if you buy cheaper and rises if prices rise, without any emission having changed.

Functional unit

The service delivered that the result is related to, and without which no comparison means anything: one watch case, a thousand parts, one year of use. Two assessments compare only if they share the same functional unit.

System boundaries

The list of what an assessment includes and what it leaves out: which stages, which flows, which geographical area, which period. Two very different results can both be correct if they do not share the same boundaries, which is why those must be declared.

Proxy

A neighbouring factor used when the right one does not exist in the databases: aluminium oxide for sapphire, a generic tanned leather for a particular one. It is an approximation openly assumed, to be flagged as such, and not a measurement.

GHG Protocol

The international framework that defines how an organisation's emissions are calculated, and in particular the split into scopes 1, 2 and 3. It is the authority when a company publishes a carbon inventory, and it is what lists the fifteen scope 3 categories.

ISO 14040

The standard that sets out the principles and framework of a life cycle assessment: the four phases, the vocabulary, the transparency requirements. It says how to think an assessment through, not how to compute a precise result.

ISO 14044

The companion standard to the previous one, setting requirements and guidelines: allocation rules, treatment of missing data, critical review. An assessment following both standards remains uncertified until an independent third party has reviewed it.

ISO 14067

The standard dedicated to the carbon footprint of products: a single indicator, climate change, with rules for quantification and communication. It is the framework for a PCF, where ISO 14040 and 14044 govern multi-criteria assessment.

CSRD

A European directive requiring a broad set of companies to publish assured sustainability information against common standards. Its effect reaches beyond those directly in scope: a company subject to it asks its suppliers for data, including outside Europe and including small ones.

ESRS E1

The climate standard of the CSRD. It requires publication of emissions across all three scopes, of reduction targets and of the transition plan. It is what turns scope 3, long optional in practice, into information to be published and assured.

SBTi

An initiative that validates corporate climate targets by checking they are compatible with a science-based pathway. It imposes minimum reduction rates and rules on scope 3 coverage. A validated target commits the company to a path, not merely to a date.

Primary coverage

The share of a scope 3.1 that rests on supplier data rather than on estimates. It is the soundness indicator of an inventory: two companies with the same total do not have the same measurement quality if one covers ten per cent and the other sixty.

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