Trust

The ISO 14064-3 assurance path

Hemera ships the evidence pack; an external assuror signs. Here's the split of responsibility.

Verified third-party assurance is an assuror's job. Hemera doesn't sign assurance opinions — we produce the evidence that lets the assurance engagement run efficiently. The split below is engagement-dependent; what an assuror needs varies by reporting context.

Evidence Hemera produces

  • Methodology PDF
    Section-by-section methodology bound to the publication snapshot.
  • Inputs hash
    SHA-256 over the canonicalised input set. Anchors every replay.
  • Monte Carlo seed
    Deterministic seed published with headline (5,000 iterations).
  • Override register
    Every override approver + ISEP credential + review note.
  • Double-count guard results
    Three checks across all 26 lines, results explicit.
  • Factor version lockfile
    Pinned DEFRA + CIBSE factor versions for the reporting period.

Gates an assuror runs

  • Sampling plan
    Risk-based sampling across emission lines and overrides.
  • Recalculation tests
    Independent recompute of sampled lines vs published figures.
  • Override interview
    Walkthrough of override decisions with the approver of record.
  • Materiality assessment
    Aggregate error vs reporting materiality threshold.

Customer responsibility

  • Primary data quality
    Survey design, response chasing, venue invoice provenance.
  • Override decisions
    Sign-off on activity-to-factor mappings where ambiguous.
  • Attestation
    Final figure attestation to the assuror at the close-out meeting.

What this demo doesn't claim

The Pawston Annual 2026 figure here is illustrative for the demo — it has not been through external assurance. The product ships the evidence pack; assurance engagements run with named partners (e.g. LRQA / Bureau Veritas / similar). In the real product, a published figure carries an assurance status flag and links to the assuror's opinion.