In the previous article, we discussed when SMEs should begin addressing Scope 3 emissions. Now, the next question is: how they should approach it? Truth be told, attempting quantification of all fifteen Scope 3 categories at the outset is not efficient. A screening assessment is a much better option.
Begin with a Screening Assessment
A screening assessment is an efficient way to identify which categories are likely material and therefore warrant deeper analysis. Although Scope 3 includes fifteen categories under the Greenhouse Gas Protocol, in practice only a subset will drive the majority of emissions for a given business model.
A screening assessment typically involves:
- Reviewing procurement and operational data to identify high-spend or high-volume activities.
- Applying spend-based emission factors to estimate likely emissions magnitude.
- Consulting sector-specific guidance where available.
- Documenting assumptions and limitations transparently.
Spend-based methods are appropriate at this stage. While less precise than supplier-specific data, they allow organizations to approximate emissions hotspots and prioritize effort logically.
Benchmark Against Peers and Competitors
Peer and competitor benchmarking serves two important functions. First, it helps organizations understand how similar companies are defining material categories and disclosure boundaries. Second, it clarifies market expectations and may even hint at emerging reporting norms.
Benchmarking does not replace technical accounting but it provides context for decision-making and strategic positioning.
Prioritize Categories Deliberately
Following screening and benchmarking, the next step is prioritization. For many SMEs, Category 1 (Purchased Goods and Services) and Category 2 (Capital Goods) represent the most significant upstream drivers. These categories frequently account for the largest share of value-chain emissions and can be estimated at an initial stage using spend-based methods.
Other categories should be evaluated through three practical lenses:
Materiality: Is the category likely to represent a meaningful portion of total emissions?
Data reliability: Can information be obtained consistently and defended if scrutinized?
Influence: Does the organization have the ability to shape outcomes through supplier engagement or procurement strategy?
For example, Category 6 (Business Travel) is often calculated early because the data is readily available. However, for most organizations, it represents a relatively small fraction of total Scope 3 emissions. Accessibility should not drive strategy.
Scope 3 is often the largest component of a company’s emissions profile. It is also the most complex. A structured, sequenced approach allows SMEs to address value-chain emissions defensibly, without compromising accuracy or strategic positioning.