How to

How to document merch program impact — CO₂, water, materials, social

Documenting impact is not painting the box green: it is producing signed per-lot evidence with comparable metrics, aligned to recognised frameworks (GHG Protocol, SBTi, GRI, SASB), packaged in a report that withstands internal audit, the customer's ESG report and PROFECO scrutiny.

See the 7 steps Templates and references

What documenting impact is (and is not)

Impact documentation in Mexican corporate merch is misunderstood when it is reduced to a polished infographic with rounded numbers. Serious audit demands comparable numbers, declared methodology, archived evidence and a responsible signature. A claim like "300 kg of CO₂ avoided" without methodology, without source lot and without date is useless for an ESG report; a claim with GHG Protocol Scope 3 methodology, production lot and five-year signed archive is useful.

The correct merch impact framework rests on five categories. The first is materials: kg of organic cotton, kg of rPET, kg of recycled steel, m² of FSC cardboard, percentage of recycled content per piece. The second is carbon: kg of CO₂e avoided per unit versus the conventional alternative, with declared methodology (GHG Protocol Scope 3, ISO 14067 or equivalent). The third is water: litres saved versus the conventional process, especially relevant for cotton textile. The fourth is social: jobs generated, labour certifications (Fair Trade, SA8000), training hours. The fifth is waste: kg of waste avoided by reusable or compostable packaging.

The Mexican regulatory framework touches several points: NOM-141 regulates recycled-content claims in textile, PROFECO monitors advertising without evidence, LFPDPPP applies if the report includes individual employee or customer data, and the Ley General de Cambio Climático defines national targets that the corporate report may cite as context. Corp-Merch.MX ships with each lot a signed report that crosses the five categories with its methodology and five-year archive.

The international frameworks the report must align to are four: GHG Protocol (especially Scope 3 category 1, purchased goods and services), SBTi (Science Based Targets initiative, to set reduction targets aligned with 1.5 °C), GRI (Global Reporting Initiative Standards, especially GRI 301 materials and GRI 305 emissions), and SASB (now part of ISSB, with sector-specific metrics). The report that crosses the five categories and aligns to these frameworks passes the auditor's test.

Before documentation starts, three documents need to be on the table: the customer's internal sustainability policy (which claims are authorised and which are not), the program master catalogue (with materials and suppliers per SKU), and the list of events or campaigns to be documented in the period (usually annual). Without these three inputs, the report is drafted in the abstract.

Corp-Merch.MX has run on this architecture for four years: 14 audited workshops, 480 active SKUs, signed report per lot from 100 pieces in textile, 200 in recycled drinkware and 500 in FSC packaging. Per-lot traceability is kept for five years; numbers are reported to the customer monthly and consolidated annually for the corporate ESG report.

The 7 steps to document impact

  1. Define the scope and the categories to document — agree with the customer which of the five categories (materials, carbon, water, social, waste) are included and at what depth. Some categories have easy data (materials), others require external methodology (Scope 3 carbon).
  2. Collect primary data per lot — for each lot: piece count, material per SKU, unit weight, fabric or polymer batch, supplier, production date, workshop electricity consumption when available. Primary data is the calculation base; without it the report stays at the approximation level.
  3. Apply the calculation methodology — for Scope 3 carbon, emission factors from the Mexican database (SEMARNAT, SECTUR) or international ones (DEFRA, Ecoinvent) depending on report destination. For water, factors from the Water Footprint Network. For recycled content, declaration from the primary supplier with certified percentage.
  4. Validate data against supplier documentation — every claim is backed by a document: GOTS or GRS scope certificate, recycler batch declaration, workshop electricity consumption letter, FSC certificate of the paper lot. Without a document, the claim does not enter the report.
  5. Build the per-lot report and the annual consolidated report — the per-lot report is delivered with each shipment, digitally signed by Corp-Merch.MX and the workshop. The annual consolidated report sums the year's lots, aligns to GHG Protocol, SBTi, GRI and SASB, and attaches to the corporate ESG report.
  6. Submit to internal and external review when applicable — before publishing the annual consolidated, internal review by the customer (sustainability, procurement, legal). For reports published to investors or customers, external review by an accredited environmental auditor.
  7. Archive for five years and leave auditable traceability — all primary documents, calculations, certificates and signed reports are archived in PDF with SHA-256 hash in a per-lot folder. Traceability allows responding to an SAT, PROFECO or external auditor enquiry in less than 48 hours.

Common mistakes that cost credibility

The first mistake is publishing the number without methodology. The claim "we saved 10 tonnes of CO₂" without declared emission factor, source lot and comparator is useless. Any auditor or journalist who asks for the number ends up finding the void.

The second mistake is confusing recycled with recyclable. Recyclable describes a capacity; recycled describes content. A piece of virgin polyethylene labelled "100 % recycled" is misleading advertising under NOM-141 and PROFECO; the sanction can reach product withdrawal and a fine.

The third mistake is mixing apples with pears. Mixing kg of organic cotton with kg of rPET and kg of recycled steel in a single aggregate number communicates nothing. A serious report disaggregates by material, category and functional unit, and only sums where methodology allows it.

The fourth mistake is signing the report without having seen the primary documentation. The report must be traceable: every number points to a document, every document to a lot, every lot to a SKU. Without traceability, the report does not survive an audit.

The fifth mistake is not updating the emission factors. DEFRA and Ecoinvent factors are updated annually; using a 2020 factor in a 2025 report distorts the number. Corp-Merch.MX refreshes its factors every year and declares the version used in the report.

The sixth mistake is forgetting the social dimension. A program with excellent environmental metrics but questionable labour conditions is not ESG, it is social greenwashing. The social category (employment, training, labour certifications) is as reportable as the environmental one and must be in the report.

Templates, references and tools

Signed per-lot report: PDF with SKU, quantity, weight, material with recycled or organic percentage when applicable, kg of CO₂e avoided versus conventional, litres of water saved when applicable, kg of waste avoided by reusable packaging, lot number, date, SHA-256 hash and digital signature. Corp-Merch.MX ships a standard template with these nine sections.

Annual consolidated report: sum of the year's lots, aligned to GHG Protocol Scope 3 category 1, SBTi (1.5 °C alignment), GRI 301 and GRI 305, SASB sector metrics. Annexed to the corporate ESG report. External review by accredited auditor when published to investors.

Emission factor catalogue: DEFRA (UK), Ecoinvent (Switzerland), SEMARNAT (Mexico) and local databases when available. Version declared in every report. Corp-Merch.MX uses DEFRA 2024 plus local adjustments for Mexican grid electricity mix.

Methodology framework: GHG Protocol Corporate Standard and Scope 3 Standard; ISO 14067 (product carbon); ISO 14046 (water footprint); GRI Standards; SASB Materiality Map; SBTi Guidance.

Mexican regulatory references: NOM-141 (recycled-content claims in textile); Ley General de Cambio Climático (national targets); PROFECO (advertising without misleading claims); LFPDPPP (personal data); NMX-AA-140 (verification of environmental reports).

Calculation tools: spreadsheet with macros for small programs; Sustainability platform like Watershed, Persefoni or IBM Environmental Intelligence for programs with extensive Scope 3; API with Ecoinvent for automated integrations. Corp-Merch.MX ships the base spreadsheet and, for clients with extensive Scope 3, integrates with the customer's platform.

Suggested cadence: week 1, scope and categories defined; weeks 2-3, primary data collection per ongoing lot; week 4, methodology applied and validated against documents; week 5, annual report draft; week 6, internal customer review; weeks 7-8, external review when applicable and publication; continuous five-year archive with SHA-256 hash.