Boundaries | Normalisation

 

This section offers more technical guidance to use the OECD Sustainable Manufacturing Indicators effectively, including facility mapping, boundaries, normalisation, data interpretation and scenario comparison.

 

Boundaries of measurement

This Toolkit primarily focuses on measuring the direct environmental impacts from the facility, the materials it consumes and the products it manufactures. However, you should be aware that there are also other indirect impacts related to your production – for example, energy may also be consumed during the refining processes of the materials you use, resulting in greenhouse gas emissions.

As your experience deepens, we encourage you to consider the impacts beyond your natural organisational boundary and expand your indicator coverage to include impacts associated with your supply chain, such as:

• Water consumed during the production of inputs (particularly where this is relevant in water-stressed regions) – as an extension of Indicator O1
• Energy consumed during the production of inputs (materials and intermediate products) – as an extension of Indicator O2
• Greenhouse gas emissions caused during the production of inputs – as an extension of Indicator O4

You might also consider greenhouse gas emissions associated with logistics – as an extension of Indicator O4, particularly:

• Shipping of materials from suppliers to your facility
• Staff commuting
• Shipping of finished products to their final destinations

Data for those items can be obtained or estimated from different sources:

• Directly survey suppliers and logistics companies (and employees in the case of staff commuting)
• Use ‘water footprint’ and ‘carbon footprint’ tools
• Use conversion tables or lifecycle inventory data for calculating carbon emissions, and energy and water consumption ‘embedded’ in inputs.

When extending your indicator coverage, be sure to record clearly what your boundary is and any related assumptions. The Data Tools section provides links to existing tools and conversion tables.

 

 

Normalisation

A majority of the OECD Sustainable Manufacturing Indicators are “normalised”. Instead of using the total amount, the indicators are presented in relative terms as a ratio of performance per specific unit of output (“intensity”). The indicators to which this applies are I1, I2, O1, O2, O4, O5, O6, O7, P4, P6 and P7. What this means is that, instead of simply reporting a total amount, the indicator for water intensity (O1), for example, is defined as water consumption per unit of output from your facility. Normalisation helps users understand performance in a particular context. If, on the other hand, water were only measured as a total consumption figure, it would change according to levels of production and would not provide any real insight to water efficiency or allow a comparison with other facilities.

A variety of factors may be used to normalise performance, including:

• Number, weight or units of products produced in the facility.
• Sales or value added in the facility.
• Person-hours worked in the facility.
• Units of function or level of services to be provided by the products produced in the facility.
• Lifetime of the products produced in the facility.

While Indicator P4 specifies the use of product lifetime as a normalisation factor, you may choose the factors that are most relevant to your businesses for other intensity indicators.

In order to get the best use out of the indicators and improve your performance, it is important to use the defined normalisation factor consistently over time. You should also use the normalisation factor used by any peers against which you would like to benchmark your own performance, e.g. other facilities in your business or competitors. Your industry or trade associations may provide standard factors to be applied in your sector.