> For the complete documentation index, see [llms.txt](https://kb.bravegen.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kb.bravegen.com/carbon/core-concepts/inventory-items.md). # Inventory Items Organisation and categorisation of your carbon emission inventory, in alignment with GHG Protocol and other reporting frameworks. Inventory items and templates define how activity data becomes reportable emissions data. An **Inventory Item** holds the calculation and reporting setup for a specific source assignment. An **Inventory Item Template** lets you define that setup once and reuse it across many entities. ## Inventory items An Inventory Item tells BraveGen Carbon how to convert a [Source's](/carbon/core-concepts/activity-sources.md) raw activity data into a reportable emissions line. The Inventory Item — not the Source itself — stores: * The emission factor group used for the calculation * The unit of measure, including any standardised unit conversion * The reporting categorisation, including GHG Protocol, ISO 14064:2018, NGERS, PCAF, and custom frameworks * Tags, effective dates, and the reporting name A single Source can map to more than one Inventory Item through a Rule. Use this when different parts of the same activity need different factors or reporting treatment. ## Inventory item templates An Inventory Item Template is a reusable definition of an Inventory Item's configuration. Create and manage templates in **Settings**. Templates use the same fields as the Inventory Items created from them. {% hint style="warning" %} Templates are **live**. Editing a template updates every Inventory Item linked to it. You are editing a shared definition, not a one-time copy. {% endhint %} ### How templates connect to inventory items Templates are not assigned directly to entities. The flow works like this: 1. A [**Template**](/carbon/core-concepts/inventory-items/inventory-templates.md) defines the calculation and reporting setup. 2. A [**Rule**](/carbon/core-concepts/inventory-items/inventory-rules.md) references one or more templates. 3. That Rule is assigned to an **Activity Source** at an entity during **Task Review**. That Rule assignment creates and governs the Inventory Item for that source. To change which template applies, update the Rule assignment on the Source. ### Create a template In **Settings**, select **New Inventory Template**. The template form is grouped into four sections. #### General | Field | Description | | ---------------------- | -------------------------------------------------------------------------------------- | | Template Name | A unique name for reuse and lineage. Use this name when finding the template in Rules. | | Source Unit of Measure | The expected unit for incoming activity data. Include currency where relevant. | | Tags | Optional labels for grouping Inventory Items in review and reporting. | #### Emission factor group Attach the emission factor group used to calculate emissions from the activity data. This field is optional. Leave it blank when the activity should not calculate emissions. If the incoming data already arrives as `kgCO₂e` or `tCO₂e`, use a pre-calculated emission factor. This adds the value directly to totals instead of recalculating it. If the source unit and factor unit do not match, add a calculation or unit conversion first. For example, convert `Wh` to `kWh` before applying a factor defined in `kWh`. **Reporting Inclusion** controls which Scope 2 or Scope 3 view the item contributes to: * **All** * **Market Based** * **Location Based** {% content-ref url="/pages/8U80bFH23hBUVYq1E9Ua" %} [Market & Location Based Reporting](/carbon/configuration/reporting-frameworks/ghg-protocol/market-and-location-based-reporting.md) {% endcontent-ref %} #### Calculation Use calculations to transform source activity data before emissions are calculated. Common uses include: * Converting units * Subtracting a renewable portion * Applying a fixed multiplier Select **+ Calculation** to add a formula step. Select **+ Unit Conversion** to add a unit conversion step.

Adding a calculation step

Each calculation step includes a description and an expression. Use `a` as the input value. For example, `a*1.1`. Calculation steps run in sequence. The result appears in the Inventory Item **Calculation** tab as part of the stepped calculation output. #### Reporting | Field | Description | | ----------------------- | ------------------------------------------------------------------------------------------------------------------------------------- | | Inventory Item Name | The name shown in reports and used for grouping. For example, `Well to Tank Losses`. | | GHG Protocol | Enable and map the item to a GHG Protocol scope and category. | | ISO14064:2018 | Enable and map the item to an ISO 14064:2018 category. | | NGERS Source | Enable and map the item to an NGERS source and measurement criterion. | | PCAF Asset Class | Select a PCAF asset class. This is available only if PCAF reporting is enabled and GHG Protocol field is set to Scope 3, Category 15. | | Standardised Units | Convert the calculated activity into a standard unit with a conversion factor. This runs after any calculation steps above. | | Custom Framework fields | Apply a category from your organisation's custom reporting frameworks. | | Exclude Emissions | Exclude the item from total emissions. The item still appears in reports, and an exclusion reason is required. | Only the frameworks enabled for your organisation appear here. Once the required fields are complete, select **Create Template**. ### Editing a template Editing a template immediately affects every Inventory Item linked through a Rule. {% hint style="warning" %} Before changing a template used across many entities, check the reporting impact. Changes to emission factors, calculations, or framework mappings can alter historical totals and disclosures everywhere the template is applied. {% endhint %} ### Override fields on an individual inventory item Most Inventory Item fields stay synced to the template and cannot be edited directly. You can override these fields independently on an inventory item: * **Reporting Name** * **Tags** * **Effective Dates** To change any other field, update the template or change the Rule assignment in Gatekeeper. ### Summary * Inventory Items calculate and categorise activity data at the entity level. * Inventory Item Templates define that configuration once for reuse. * Rules connect templates to sources during Task Review. * Template edits propagate to every linked Inventory Item. * Only **Reporting Name**, **Tags**, and **Effective Dates** can be overridden on the item itself.