| Level | Codes | Note |
|---|---|---|
| Green Dict HS6 | 372.0 | Product-level granularity |
| HS6 matched to NAICS | 349.0 | 94% coverage (Census Schedule B) |
| NAICS 6-digit codes | 107.0 | Industry-level granularity |
| Compression ratio | 3.3 | HS6 per NAICS on average |
HS→NAICS Concordance: Many-to-One Correspondence and Granularity Loss
How aggregation to NAICS level conflates distinct clean-tech value chains
1 Overview
The NZIPL Green Dictionary maps 372 HS6 product codes across 10 clean technologies to four value-chain stages. Using the official US Census Bureau Schedule B → NAICS concordance (2024), 349 of those HS6 codes resolve to 107 unique NAICS 6-digit industry codes — a 3.3× compression.
Important
The granularity problem: When multiple clean-tech HS6 codes map to the same NAICS code, any firm-level query on that industry (via S&P Capital IQ Pro, ORBIS, Compustat, etc.) cannot distinguish a solar-panel manufacturer from a wind-turbine manufacturer, or a battery-grade lithium miner from a copper miner. The clean-tech signal collapses into a broad industrial bucket.
2 Distribution of HS6 codes per NAICS code
| tier | NAICS codes | HS6 codes affected | Cross-tech NAICS (2+ techs) |
|---|---|---|---|
| 1 — Unique | 41 | 41 | 7 |
| 2 — Low (2–3) | 40 | 95 | 28 |
| 3 — Medium (4–8) | 20 | 107 | 18 |
| 4 — High (9+) | 7 | 114 | 7 |
Of the 108 NAICS codes that cover green dictionary products:
- 41 are unique — clean, one-to-one HS6→NAICS; firm queries are precise.
- 7 are high-severity (9+ HS6 each) — these aggregate dozens of distinct clean-tech products, spanning multiple technologies, into a single industry bucket.
3 Cross-technology aggregation
The most analytically damaging cases are NAICS codes shared by products from multiple clean technologies. A single NAICS query returns manufacturers of solar cells, wind bearings, and battery chemicals indiscriminately.
| NAICS | Industry | HS6 | Techs | Technologies | Stages |
|---|---|---|---|---|---|
| 212290 | Other Metal Ore Mining | 12 | 10 | Batteries; Biofuel; Electrolyzers; Geothermal; Heat Pumps; Magnets; Nuclear; Solar; Transmission; Wind | Upstream |
| 212230 | Copper Ore Mining | 4 | 10 | Batteries; Biofuel; Electrolyzers; Geothermal; Heat Pumps; Magnets; Nuclear; Solar; Transmission; Wind | Upstream |
| 325180 | Other Basic Inorganic Chemical Mfg | 37 | 8 | Batteries; Biofuel; Electrolyzers; Geothermal; Magnets; Nuclear; Transmission; Wind | Downstream; Midstream; Upstream |
| 333517 | Die-Cutting Machinery Mfg | 15 | 8 | Batteries; Electrolyzers; Geothermal; Heat Pumps; Magnets; Solar; Transmission; Wind | Downstream; Midstream |
| 333998 | All Other General Purpose Machinery Mfg | 4 | 8 | Batteries; Biofuel; Electrolyzers; Geothermal; Magnets; Nuclear; Solar; Wind | Downstream; Midstream |
| 333248 | All Other Industrial Machinery Mfg | 10 | 7 | Batteries; Electrolyzers; Geothermal; Magnets; Nuclear; Solar; Wind | Downstream; Final Product; Midstream |
| 331313 | Alumina Refining & Primary Aluminum Prod | 3 | 7 | Batteries; Biofuel; Heat Pumps; Magnets; Solar; Transmission; Wind | Downstream; Midstream |
| 331110 | Iron & Steel Mills and Ferroalloy Mfg | 16 | 6 | Batteries; Geothermal; Magnets; Nuclear; Transmission; Wind | Downstream; Final Product; Midstream; Upstream |
| 331410 | Nonferrous Metal Smelting & Refining | 12 | 6 | Batteries; Biofuel; Electrolyzers; Heat Pumps; Solar; Wind | Midstream; Upstream |
| 333912 | Vacuum Pump & Compressor Mfg | 5 | 6 | Batteries; Biofuel; Electrolyzers; Geothermal; Heat Pumps; Wind | Downstream; Midstream |
| 325211 | Plastics Material and Resin Mfg | 12 | 5 | Batteries; Electrolyzers; Geothermal; Solar; Wind | Downstream; Midstream |
| 332410 | Power Boiler & Heat Exchanger Mfg | 8 | 5 | Biofuel; Electrolyzers; Geothermal; Heat Pumps; Nuclear | Downstream; Final Product; Midstream |
| 333310 | Commercial & Industrial Machinery Repair | 6 | 5 | Batteries; Biofuel; Electrolyzers; Geothermal; Wind | Downstream; Midstream |
| 333994 | Industrial Process Furnace & Oven Mfg | 4 | 5 | Geothermal; Magnets; Nuclear; Solar; Transmission | Downstream; Midstream |
| 333241 | Food Product Machinery Mfg | 2 | 5 | Batteries; Biofuel; Electrolyzers; Nuclear; Transmission | Downstream; Midstream |
| 335220 | Household Appliance Mfg | 1 | 5 | Batteries; Magnets; Solar; Transmission; Wind | Downstream; Midstream |
| 333519 | Other Metalworking Machinery Mfg | 5 | 4 | Batteries; Electrolyzers; Geothermal; Transmission | Downstream; Midstream |
| 333992 | Welding & Soldering Equipment Mfg | 4 | 4 | Geothermal; Heat Pumps; Solar; Wind | Downstream; Midstream |
| 212210 | Iron Ore Mining | 2 | 4 | Batteries; Geothermal; Nuclear; Transmission | Upstream |
| 325199 | All Other Basic Organic Chemical Mfg | 6 | 3 | Batteries; Biofuel; Wind | Final Product; Midstream |
| 333415 | A/C & Refrigeration Equipment Mfg | 6 | 3 | Biofuel; Electrolyzers; Heat Pumps | Downstream; Final Product; Midstream |
| 333611 | NAICS 333611 | 5 | 3 | Geothermal; Nuclear; Wind | Downstream; Final Product |
| 325212 | NAICS 325212 | 4 | 3 | Batteries; Electrolyzers; Geothermal | Midstream |
| 335999 | NAICS 335999 | 4 | 3 | Electrolyzers; Magnets; Wind | Downstream; Midstream |
| 212390 | NAICS 212390 | 3 | 3 | Batteries; Geothermal; Heat Pumps | Midstream; Upstream |
| 325110 | NAICS 325110 | 3 | 3 | Batteries; Biofuel; Geothermal | Midstream; Upstream |
| 325998 | NAICS 325998 | 3 | 3 | Biofuel; Geothermal; Solar | Midstream |
| 327910 | NAICS 327910 | 3 | 3 | Geothermal; Magnets; Wind | Downstream; Midstream |
| 331318 | NAICS 331318 | 3 | 3 | Heat Pumps; Transmission; Wind | Midstream |
| 331420 | NAICS 331420 | 3 | 3 | Heat Pumps; Transmission; Wind | Midstream |
| 332999 | NAICS 332999 | 3 | 3 | Batteries; Magnets; Wind | Downstream; Final Product; Midstream |
| 333120 | NAICS 333120 | 3 | 3 | Geothermal; Transmission; Wind | Downstream; Final Product |
| 212323 | NAICS 212323 | 2 | 3 | Geothermal; Heat Pumps; Solar | Upstream |
| 327992 | NAICS 327992 | 2 | 3 | Batteries; Geothermal; Nuclear | Upstream |
| 327999 | NAICS 327999 | 2 | 3 | Batteries; Nuclear; Wind | Midstream |
| 333514 | NAICS 333514 | 2 | 3 | Electrolyzers; Heat Pumps; Magnets | Downstream; Midstream |
| 333914 | NAICS 333914 | 2 | 3 | Biofuel; Electrolyzers; Heat Pumps | Downstream |
| 333413 | NAICS 333413 | 1 | 3 | Biofuel; Electrolyzers; Geothermal | Downstream |
| 332991 | Ball and Roller Bearing Mfg | 8 | 2 | Geothermal; Wind | Midstream |
| 332991 | Ball and Roller Bearing Mfg | 8 | 2 | Geothermal; Wind | Midstream |
| 335312 | Motor and Generator Mfg | 8 | 2 | Solar; Wind | Downstream |
| 334515 | Electricity Measurement Instrument Mfg | 6 | 2 | Batteries; Wind | Downstream; Midstream |
| 326113 | NAICS 326113 | 4 | 2 | Batteries; Solar | Midstream |
| 325120 | NAICS 325120 | 3 | 2 | Biofuel; Solar | Upstream |
| 332996 | NAICS 332996 | 3 | 2 | Geothermal; Wind | Midstream |
| 333515 | NAICS 333515 | 3 | 2 | Geothermal; Wind | Downstream; Midstream |
| 325520 | NAICS 325520 | 2 | 2 | Solar; Wind | Midstream |
| 331210 | NAICS 331210 | 2 | 2 | Geothermal; Wind | Final Product; Midstream |
| 331491 | NAICS 331491 | 2 | 2 | Batteries; Solar | Midstream |
| 331492 | NAICS 331492 | 2 | 2 | Biofuel; Electrolyzers | Midstream |
| 332312 | NAICS 332312 | 2 | 2 | Solar; Wind | Downstream |
| 333993 | NAICS 333993 | 2 | 2 | Batteries; Transmission | Downstream |
| 334416 | NAICS 334416 | 2 | 2 | Transmission; Wind | Final Product; Midstream |
| 335991 | NAICS 335991 | 2 | 2 | Batteries; Wind | Midstream |
| 336310 | NAICS 336310 | 2 | 2 | Geothermal; Wind | Midstream |
| 325130 | NAICS 325130 | 1 | 2 | Biofuel; Electrolyzers | Midstream |
| 325510 | NAICS 325510 | 1 | 2 | Solar; Wind | Midstream |
| 333243 | NAICS 333243 | 1 | 2 | Biofuel; Electrolyzers | Downstream |
| 339991 | NAICS 339991 | 1 | 2 | Geothermal; Wind | Midstream |
| 339999 | NAICS 339999 | 1 | 2 | Magnets; Wind | Downstream; Final Product |
4 The five worst cases
| NAICS | Industry | HS6 codes | Techs | What gets merged |
|---|---|---|---|---|
| 325180 | Other Basic Inorganic Chemical Mfg | 37 | 8 | Battery electrolytes, biofuel catalysts, electrolyzer membrane chemicals, geothermal working fluids, rare-earth processing chemicals, nuclear uranium conversion — 8 techs, all calling the same 'inorganic chemical manufacturer'. |
| 331110 | Iron & Steel Mills and Ferroalloy Mfg | 16 | 6 | Iron and steel for structural components across Geothermal rigs, Magnet cores, Nuclear reactor vessels, Transmission towers, and Wind turbine towers — 6 techs. |
| 333517 | Die-Cutting Machinery Mfg | 15 | 8 | Die-casting and metal-forming machinery used across Batteries, Electrolyzers, Geothermal, Heat Pumps, Magnets, Solar, Transmission, Wind — 8 techs of process equipment indistinguishable at NAICS level. |
| 212290 | Other Metal Ore Mining | 12 | 10 | All 10 techs share 'Other Metal Ore Mining': lithium, cobalt, manganese (Batteries); rare earths (Magnets); uranium (Nuclear); copper (Transmission/Wind); bauxite (Solar); and more. A single NAICS query cannot separate any of these. |
| 325211 | Plastics Material and Resin Mfg | 12 | 5 | Plastics/resins: battery separators, electrolyzer membranes, geothermal insulation, solar encapsulants, wind nacelle composites — 5 techs. |
| 331410 | Nonferrous Metal Smelting & Refining | 12 | 6 | Batteries; Biofuel; Electrolyzers; Heat Pumps; Solar; Wind |
| 333248 | All Other Industrial Machinery Mfg | 10 | 7 | Batteries; Electrolyzers; Geothermal; Magnets; Nuclear; Solar; Wind |
5 Severity matrix
6 Stage collapse
Beyond cross-tech contamination, some NAICS codes aggregate products from different value-chain stages — meaning firms in that NAICS code might be suppliers of raw materials, midstream processors, or final-product manufacturers, and there is no way to distinguish them using NAICS alone.
| NAICS | Industry | HS6 | Stages | Stages merged | Technologies |
|---|---|---|---|---|---|
| 331110 | Iron & Steel Mills and Ferroalloy Mfg | 16 | 4 | Downstream + Final Product + Midstream + Upstream | Batteries; Geothermal; Magnets; Nuclear; Transmission; Wind |
| 325180 | Other Basic Inorganic Chemical Mfg | 37 | 3 | Downstream + Midstream + Upstream | Batteries; Biofuel; Electrolyzers; Geothermal; Magnets; Nuclear; Transmission; Wind |
| 333248 | All Other Industrial Machinery Mfg | 10 | 3 | Downstream + Final Product + Midstream | Batteries; Electrolyzers; Geothermal; Magnets; Nuclear; Solar; Wind |
| 332410 | Power Boiler & Heat Exchanger Mfg | 8 | 3 | Downstream + Final Product + Midstream | Biofuel; Electrolyzers; Geothermal; Heat Pumps; Nuclear |
| 333415 | A/C & Refrigeration Equipment Mfg | 6 | 3 | Downstream + Final Product + Midstream | Biofuel; Electrolyzers; Heat Pumps |
| 334413 | 334413 | 4 | 3 | Downstream + Final Product + Midstream | Solar |
| 332999 | 332999 | 3 | 3 | Downstream + Final Product + Midstream | Batteries; Magnets; Wind |
| 335910 | 335910 | 3 | 3 | Downstream + Final Product + Midstream | Batteries |
| 333517 | Die-Cutting Machinery Mfg | 15 | 2 | Downstream + Midstream | Batteries; Electrolyzers; Geothermal; Heat Pumps; Magnets; Solar; Transmission; Wind |
| 325211 | Plastics Material and Resin Mfg | 12 | 2 | Downstream + Midstream | Batteries; Electrolyzers; Geothermal; Solar; Wind |
| 331410 | Nonferrous Metal Smelting & Refining | 12 | 2 | Midstream + Upstream | Batteries; Biofuel; Electrolyzers; Heat Pumps; Solar; Wind |
| 325199 | All Other Basic Organic Chemical Mfg | 6 | 2 | Final Product + Midstream | Batteries; Biofuel; Wind |
| 333310 | Commercial & Industrial Machinery Repair | 6 | 2 | Downstream + Midstream | Batteries; Biofuel; Electrolyzers; Geothermal; Wind |
| 334515 | Electricity Measurement Instrument Mfg | 6 | 2 | Downstream + Midstream | Batteries; Wind |
| 333519 | Other Metalworking Machinery Mfg | 5 | 2 | Downstream + Midstream | Batteries; Electrolyzers; Geothermal; Transmission |
| 333611 | 333611 | 5 | 2 | Downstream + Final Product | Geothermal; Nuclear; Wind |
| 333912 | Vacuum Pump & Compressor Mfg | 5 | 2 | Downstream + Midstream | Batteries; Biofuel; Electrolyzers; Geothermal; Heat Pumps; Wind |
| 333992 | Welding & Soldering Equipment Mfg | 4 | 2 | Downstream + Midstream | Geothermal; Heat Pumps; Solar; Wind |
| 333994 | Industrial Process Furnace & Oven Mfg | 4 | 2 | Downstream + Midstream | Geothermal; Magnets; Nuclear; Solar; Transmission |
| 333998 | All Other General Purpose Machinery Mfg | 4 | 2 | Downstream + Midstream | Batteries; Biofuel; Electrolyzers; Geothermal; Magnets; Nuclear; Solar; Wind |
| 335999 | 335999 | 4 | 2 | Downstream + Midstream | Electrolyzers; Magnets; Wind |
| 212390 | 212390 | 3 | 2 | Midstream + Upstream | Batteries; Geothermal; Heat Pumps |
| 325110 | 325110 | 3 | 2 | Midstream + Upstream | Batteries; Biofuel; Geothermal |
| 327910 | 327910 | 3 | 2 | Downstream + Midstream | Geothermal; Magnets; Wind |
| 331313 | Alumina Refining & Primary Aluminum Prod | 3 | 2 | Downstream + Midstream | Batteries; Biofuel; Heat Pumps; Magnets; Solar; Transmission; Wind |
| 333120 | 333120 | 3 | 2 | Downstream + Final Product | Geothermal; Transmission; Wind |
| 333242 | 333242 | 3 | 2 | Downstream + Midstream | Solar |
| 333515 | 333515 | 3 | 2 | Downstream + Midstream | Geothermal; Wind |
| 335311 | 335311 | 3 | 2 | Downstream + Final Product | Transmission |
| 327211 | 327211 | 2 | 2 | Downstream + Midstream | Solar |
| 331210 | 331210 | 2 | 2 | Final Product + Midstream | Geothermal; Wind |
| 333131 | 333131 | 2 | 2 | Downstream + Final Product | Geothermal |
| 333241 | Food Product Machinery Mfg | 2 | 2 | Downstream + Midstream | Batteries; Biofuel; Electrolyzers; Nuclear; Transmission |
| 333514 | 333514 | 2 | 2 | Downstream + Midstream | Electrolyzers; Heat Pumps; Magnets |
| 334416 | 334416 | 2 | 2 | Final Product + Midstream | Transmission; Wind |
| 327215 | 327215 | 1 | 2 | Downstream + Midstream | Solar |
| 335220 | Household Appliance Mfg | 1 | 2 | Downstream + Midstream | Batteries; Magnets; Solar; Transmission; Wind |
| 339999 | 339999 | 1 | 2 | Downstream + Final Product | Magnets; Wind |
7 Unmatched HS6 codes: the HS revision gap
Twenty-three green-dictionary HS6 codes have no match in the Census Bureau Schedule B → NAICS concordance (2024 edition). These are not data errors — they fall into three structural categories explained below.
| HS6 code | Technology | Role | Stage |
|---|---|---|---|
| 382490 | Batteries | Product Component | Midstream |
| 390760 | Batteries | Processed Material | Midstream |
| 902780 | Batteries | Process Equipment | Downstream |
| 151000 | Biofuel | Raw Material | Upstream |
| 151490 | Biofuel | Raw Material | Upstream |
| 293290 | Biofuel | Processed Material | Midstream |
| 440110 | Biofuel | Raw Material | Upstream |
| 440130 | Biofuel | Raw Material | Upstream |
| 681510 | Biofuel | Processed Material | Midstream |
| 840619 | Biofuel | Process Equipment | Downstream |
| 854380 | Electrolyzers | Process Equipment | Downstream |
| 851430 | Electrolyzers; Geothermal | Process Equipment | Downstream |
| 846241 | Electrolyzers; Heat Pumps; Transmission | Process Equipment | Downstream |
| 730420 | Geothermal | Product Component | Downstream |
| 845610 | Geothermal | Process Equipment | Downstream |
| 846021 | Geothermal | Process Equipment | Downstream; Midstream |
| 846210 | Geothermal | Process Equipment | Downstream |
| 740110 | Heat Pumps; Transmission; Wind | Processed Material | Midstream |
| 252890 | Nuclear | Raw Material | Upstream |
| 282611 | Nuclear | Processed Material | Midstream |
| 810990 | Nuclear | Processed Material | Midstream |
| 854140 | Solar | Product Component | Downstream |
| 846221 | Wind | Process Equipment | Midstream |
Why these 23 codes are unmatched
Category 1 — HS 2017/2022 revision gap (manual mapping required)
The Census Schedule B concordance is anchored to the HS 2022 revision (current as of 2024). Some green-dictionary codes were defined for earlier HS revisions (HS2017, HS2012) and have since been split, merged, or renumbered. Nuclear and magnet codes are most affected: for example, 810990 (Zirconium and articles thereof — a key nuclear fuel-cycle material) existed through HS17 but was subdivided in HS22, and the old heading does not appear in the Census export file. Similarly, several rare-earth and magnet codes that were valid HS12/HS17 entries are absent from the HS22-based Schedule B.
These codes must be mapped manually by inspecting the WCO HS2017→HS2022 correlation table and assigning the successor NAICS code from the new heading. Until that is done, firms dealing in these specific products will be missed by NAICS-based queries.
Category 2 — Import-only Schedule B positions (not in export concordance)
The Census expconcord24.xlsx is an export concordance (Schedule B commodity codes). A small number of HS6 positions — primarily certain process-equipment headings — appear only in US import classifications (HTS, Harmonised Tariff Schedule) and have no Schedule B export equivalent. These products are imported rather than domestically manufactured at a classifiable Schedule B level, so no NAICS production code is assigned.
Category 3 — Agricultural / biofuel feedstock codes
Several biofuel feedstock codes (e.g., sugarcane, palm oil, oilseeds) are classified under agricultural chapters (HS 10–15) which the Census Schedule B covers only partially for export purposes. The Census concordance prioritises manufactured goods; primary agricultural commodities used as industrial inputs are underrepresented.
Implication for S&P Capital IQ Pro matching
Firm-level queries using NAICS will structurally miss any company whose primary product is one of these 23 HS6 codes until manual mappings are added. The gap is concentrated in Nuclear (specialty metals and reactor materials) and Magnets (rare-earth precursors) — precisely the technologies where precise firm identification matters most for industrial-policy analysis.
8 Implications for firm-level matching
8.1 False positives
A query on NAICS 325180 (Other Basic Inorganic Chemical Manufacturing) returns the entire inorganic chemicals industry. The vast majority of those firms produce acids, pigments, and industrial gases with no clean-tech relevance. The 37 green-dict HS codes mapped here are a small fraction of what that NAICS industry actually produces.
8.2 Cross-tech contamination
NAICS 212290 (Other Metal Ore Mining) covers all 10 clean technologies. Lithium miners, cobalt miners, rare-earth miners, and uranium miners are all in the same bucket. Any country-level analysis of “other metal ore mining” will conflate these entirely different supply chains.
8.3 Recommended approach
R1 — HS6 as primary key where possible
For databases with HS-level trade identifiers alongside firm records (US Census LFTTD, Indian customs microdata), match directly at HS6. This avoids NAICS aggregation entirely and preserves full product-level granularity.
R2 — Apply green-dict HS filter as a secondary screen
When a firm-level database only exposes NAICS codes, retrieve all firms in the NAICS bucket and then cross-reference against the green dictionary HS codes via the firm’s import/export activity (if available). This converts a broad industry sweep into a targeted clean-tech filter.
R3 — Flag high-severity NAICS codes in any firm-count output
NAICS 325180, 212290, 333517 each cover 8–10 clean technologies. Any firm count or market-share estimate derived from these codes alone should be labelled as an upper-bound estimate, not a clean-tech-specific figure.
R4 — The 41 unique-mapping NAICS codes are analysis-ready
41 NAICS codes have exactly one green-dict HS6 mapped to them. These are safe to use directly in firm queries with high precision: 212220, 212319, 212322, 311225, 325130, 325193, 325311, 325510, 326220, 326299, 327120, 327215, 327310, 327410, 327991, 331314, 332215, 332510, 332618, 332722, 333132, 333243, 333413, 333612, 333613, 333924, 333996, 334412, 334417, 334510, 334511, 334513, 334519, 335220, 335931, 335932, 336330, 336340, 339991, 339999, 910000.
9 Data sources
| Source | File | Notes |
|---|---|---|
| NZIPL Green Dictionary | data/green_dict/green_dictionary.csv |
372 HS6 codes × 10 techs |
| US Census Bureau | data/spatial/expconcord24.xlsx |
2024 Schedule B → NAICS concordance, 9,724 rows |
| HS6→NAICS crosswalk | data/concordance/hs6_naics_crosswalk.csv |
Built by scripts/build_data/08c_build_naics_crosswalk.R |
Rendered: 2026-04-14