Value unit - TX
Value Unit refers to the unit in which an environmental indicator or quantitative measure is expressed. It defines the scale and type of the result value, such as kilograms of CO₂-equivalent or megajoules of energy.
Value Units are essential for ensuring comparability, validity, and consistency across Life Cycle Assessment (LCA) declarations and sustainability data exchange using the IMDE model.
Purpose
The Value Unit indicates the unit of measurement for the value being reported, independently of what it is reported *per* (e.g., per kilogram or per functional unit). It answers the question: “What is the quantity expressed in?”
Examples
Common Value Units used for environmental impact indicators include:
- kg CO₂eq – Kilograms of carbon dioxide equivalent (for Climate Change)
- m³ – Cubic meters of freshwater (for Water Use)
- MJ – Megajoules (for Primary Energy Demand)
- kg Sb eq – Kilograms of antimony equivalent (for Resource Use)
- kg PM2.5 eq – Kilograms of fine particulate matter equivalent (for Air Pollution)
Characteristics
- May be expressed as standard SI units (e.g., kg, m³, MJ)
- May be expressed as derived or compound units (e.g., kg CO₂eq, MJ primary energy, kg Sb eq)
- Units should be consistent with international LCA standards (e.g., ILCD, PEF, EN 15804)
Use in IMDE
The Value Unit is part of the environmental impact declaration structure in IMDE and is applied per Indicator:
- Example:
* Indicator: Climate Change Potential (CFP) * Value: 0.98 * Value Unit: kg CO₂eq * Declared Unit: per kg (see Declared Unit - TX)
This separation ensures reusability of indicators across products, geographies, and life cycle stages while preserving semantic clarity.
