How to Import a BOM Into LCA Software Step by Step

Importing a bill of materials into LCA software is not the same as completing an LCA. The import creates structured product data. You still need to check quantities, reference flows, boundaries, dataset choices, geography, manufacturing inputs, transport, packaging, assumptions, and gaps before calculating defensible results.

Start with the model you need to build

An engineering BOM usually describes what is assembled, not the complete life cycle. It may contain part numbers, descriptions, quantities, revisions, suppliers, and parent assemblies. LCA inputs can also include materials, energy, emissions, waste, utilities, transport, packaging, and other flows, as outlined in Ecochain’s LCA data-collection guidance.

Before editing the spreadsheet, define:

• The product or declared unit
• The system boundary
• The BOM version and product variant
• Which manufacturing, transport, use, maintenance, and end-of-life stages are in scope
• Whether the assessment needs supplier-specific data or can begin with secondary datasets
• How assumptions and unresolved rows will be documented

This prevents a technically successful upload from becoming the wrong model.

Prepare the BOM for import

Use one row per distinct component relationship rather than one row per unique part. A repeated fastener used by several assemblies should retain each parent-child relationship unless the target software explicitly handles a separate part master and relationship table.

At minimum, each row needs an identifiable item, a quantity, and a unit. One Click LCA’s early-access importer requires three fields for every item: description, quantity, and unit. Earthster’s simple Generator table instead has five mandatory columns: cycle, component, amount, unit, and geography. These are software-specific requirements, not a universal LCA schema.

A practical source workbook can separate:

The exact columns must follow the selected importer. For example, Earthster can use an optional depth field for nested structures, while Ecochain Mobius requires imported data to follow its predefined structure.

Preserve multi-level assemblies

Flattening a multi-level BOM can hide where components belong and create double counting. Retain the parent, child, quantity-per-parent, variant, and revision wherever the import format allows it. An optional depth field can also express hierarchy; Earthster documents this approach for nested product structures.

Review shared and phantom assemblies separately. If a subassembly appears as both an assembly total and a list of its children, importing both environmental loads would count the same content twice. Decide whether the model calculates the subassembly from its children or treats it as a pre-modelled input.

Map columns, units, and classifications

A typical import moves from file upload through settings, column mapping, review, unit and classification checks, data combination, dataset mapping, and completion. One Click LCA documents that sequence and can also save column mappings and process multiple Excel sheets.

Do not treat unit conversion as clerical cleanup. A quantity in pieces is not automatically a physical reference flow. It may need conversion using component mass, dimensions, composition, or a component-specific model. One Click LCA supports metric and imperial units but flags conversions it cannot complete. For the underlying concepts, see this guide to LCA units explained.

Check every conversion involving:

• Pieces to mass
• Length or area to mass
• Wet mass to dry mass
• Concentration to constituent mass
• Purchased quantity to incorporated quantity
• Gross input to net product after scrap

Keep the original value and unit alongside the converted flow. That makes later review possible without reconstructing the source file.

Match each item to an appropriate dataset

A material name is not enough to select an LCA dataset. “Aluminium,” for example, does not identify the production technology, geography, reference product, unit, recycled-content treatment, or system model. Dataset mapping therefore needs human review even when software proposes a match.

For each row, check:

• Material or process represented
• Dataset reference product
• Geography and market coverage
• Unit and conversion factor
• Production technology
• Whether the dataset represents material production, processing, or both
• System model and methodological consistency
• Data age and suitability
• Supplier evidence or proxy rationale

Keep source labels when possible. XYCLE says imported BOM and inventory data can retain source labels for traceability, while also emphasizing primary supplier data and visibility into assumptions.

Understand what different importers accept

Import tools do not all solve the same problem. Some ingest product spreadsheets, while others exchange structured LCA processes or databases. That distinction affects how much preparation and mapping must happen before calculation.

Validate the imported model

Never accept an imported model based only on a successful status message. Review the structure and resulting inventory before running impact assessment.

Use this validation checklist:

• Every expected BOM row is imported or deliberately excluded
• Parent-child relationships remain intact
• Shared and phantom assemblies are not double counted
• Quantities reconcile with the selected product unit
• Units and conversion factors are correct
• Material composition totals are plausible
• Manufacturing energy, consumables, scrap, emissions, and waste are represented
• Transport and packaging are included where required by scope
• Dataset technology and geography are suitable
• Proxies and exclusions are documented
• Unmapped rows remain visible
• Supplier evidence is linked to the relevant part or material

Prioritize improvements by impact contribution, mass, uncertainty, and the availability of better supplier data. High-mass components deserve attention, but a low-mass material can still dominate an impact category.

Make BOM revisions part of the workflow

A BOM import should not be a one-time transfer. When a revision changes quantities, materials, suppliers, manufacturing locations, or assembly structure, compare it with the previous version. Reuse mappings that remain valid, review changed rows, recalculate results, and preserve unresolved gaps. This guide explains how to update an LCA when the BOM changes.

Dawn is built around this living-model approach: Excel or CSV parts can be maintained with assemblies, variants, versions, LCA studies, suppliers, and files through product and LCA data management, assembly version control, and supplier data collection. The same inventory can support carbon results and EPD-style table exports, but a product carbon footprint and an EN 15804 study are not the same by default, and EPD verification remains a human process outside the app.

Sources

• Sphera LCA BOM Import
• One Click LCA bill of materials AI import
• One Click LCA standard import process
• Earthster Generator documentation
• Ecochain LCA input-data guidance
• Ecochain Mobius data import documentation
• Athena BOM Import Utility
• SimaPro supported import and export formats
• openLCA database import documentation
• XYCLE product information