# Quality Assurance and Oversight | Grid and Regions methodology
Source: https://greenpixie.com/docs/methodology/grid/quality-assurance

Standards alignment, validation, and review controls.

## 9.1 Standards Alignment [#91-standards-alignment]

The methodology is aligned to the GHG Protocol and prepared with reference to ISO 14064-1.

Factors are calculated on a location-based basis in accordance with the GHG Protocol Scope 2 Guidance. The transmission and distribution component is prepared on the basis the GHG Protocol Corporate Value Chain (Scope 3) Standard sets out for Category 3.

## 9.2 Comparison Before Publication [#92-comparison-before-publication]

Before publication, Greenpixie compares every new set of factors against the currently published set over the past hours both sets cover. Each source carries a revision window, being the period over which that source revises figures it has already published. An hour inside its source's revision window may move, within a tolerance set for that source. Where an hour older than that window moves, the comparison fails. A failed comparison stops publication by default.

## 9.3 Component and Validity Checks [#93-component-and-validity-checks]

On every calculation, Greenpixie runs component and validity checks. A figure that fails any of those checks stops publication for that period by default. The previously published set then stands.

## 9.4 Source Verification [#94-source-verification]

Greenpixie's reproduction check compares a configured emission factor, loss figure or fixed published figure with a retained copy of the publisher's own material. The check fails where the configured value and the retained copy disagree. Where a factor comes from a national publisher, the value reproduced against the retained copy is that publisher's combustion figure. From that figure Greenpixie derives the lifecycle total carried alongside it, using the ratio between the two that the Intergovernmental Panel on Climate Change publishes for the fuel. Before each update, Greenpixie checks the retained copies against the hashes recorded when they were retained. Periodically, Greenpixie runs the reproduction check.

Before using a source, Greenpixie records its licence position, being the terms its publisher grants alongside the use the methodology makes of that source.

## 9.5 Cloud Region Location Verification [#95-cloud-region-location-verification]

From a billed cloud region to its factor, Greenpixie checks each step on its own, being whether the cloud region has a configured entry, where its cloud provider has published the cloud region to be, which grid areas serve that location, and the weights by which those areas combine. Every check runs against retained published evidence. For each of the 85 configured United States cloud regions, Greenpixie records how well that cloud region's location is evidenced.

## 9.6 Academic and Technical Review [#96-academic-and-technical-review]

In collaboration with academic partners including Professor Alex Rogers at the University of Oxford, Greenpixie validates the grid carbon intensity methodology and its data selection.