NAICS 335991

Overview

The North American Industry Classification System (NAICS) is the federal standard for classifying business establishments to support consistent collection, analysis, and publication of statistics on the U.S. economy. Developed under the Office of Management and Budget with partners in Canada and Mexico, NAICS replaced the SIC system in 1997 and is currently published in the 2022 vintage. ¹

NAICS 335991 covers establishments primarily engaged in manufacturing carbon, graphite, and metal‑graphite brushes and brush stock; carbon or graphite electrodes used for thermal and electrolytic applications; carbon and graphite fibers; and other carbon, graphite, and metal‑graphite products. Carbon or graphite gaskets are excluded from this industry and classified in NAICS 339991. ²

What this NAICS covers

• Manufacturing carbon, graphite, and metal‑graphite brushes and brush stock. ²
• Producing carbon or graphite electrodes for thermal (e.g., electric arc furnaces) and electrolytic uses. ²
• Manufacturing carbon fibers and graphite fibers. ²
• Fabricating other carbon, graphite, and metal‑graphite products not otherwise specified. ²
• Products serving electrical applications such as brushes and electrodes integral to motors, generators, and electrolytic cells. ²
• Excludes carbon or graphite gaskets, which fall under NAICS 339991. ²

Related NAICS and PSC codes

Type	Code	Descriptor
NAICS	339991	Gasket, Packing, and Sealing Device Manufacturing (carbon/graphite gaskets are classified here). 2
NAICS	335999	All Other Miscellaneous Electrical Equipment and Component Manufacturing (explicitly excludes carbon and graphite products, which are classified in 335991). 2
PSC	5977	Electrical Contact Brushes and Electrodes (includes carbon brush stock and lighting electrodes). 3
PSC	9350	Refractories and Fire Surfacing Materials (covers refractory materials; graphite refractories are procured under this PSC when applicable). 3

Industry boundaries and notable exclusions

• Included outputs: carbon/graphite/metal‑graphite brushes and brush stock; carbon/graphite electrodes; carbon and graphite fibers; other carbon/graphite items. ²
• Explicit exclusion: carbon or graphite gaskets are classified in NAICS 339991, not 335991. ²
• PSC alignment highlights: procurement of brushes/electrodes commonly maps to PSC 5977; refractory products with graphite content may map to PSC 9350. ³

2022 NAICS implementation context

The Census Bureau began disseminating data on the 2022 NAICS basis with 2022 Economic Census releases and plans to transition remaining NAICS‑based programs by the end of calendar year 2027. Users should confirm which vintage a dataset uses when analyzing 335991 statistics. ⁴

Frequently asked questions

• What products fall under NAICS 335991?
  This industry includes carbon, graphite, and metal‑graphite brushes and brush stock; carbon or graphite electrodes for thermal and electrolytic applications; carbon and graphite fibers; and other carbon/graphite products. ²

• Are carbon or graphite gaskets part of 335991?
  No. Carbon or graphite gaskets are classified in NAICS 339991 (Gasket, Packing, and Sealing Device Manufacturing). ²

• Which PSCs commonly align with purchases in this space?
  PSC 5977 covers electrical contact brushes, brush stock, and electrodes; refractory items may fall under PSC 9350 when applicable. PSC selection depends on the item being procured. ³

• Did the 2022 NAICS revision change the definition of 335991?
  Not specified by official sources. ²

• When will federal datasets fully reflect the 2022 NAICS for 335991?
  Census programs began publishing on 2022 NAICS with the 2022 Economic Census and plan full adoption across remaining programs by the end of 2027; some exceptions transition later. ⁴

Useful resources

• G2X — NAICS 335991 overview
• U.S. Census Bureau — NAICS main page and 2022 NAICS resources. ¹
• U.S. Census Bureau — NAICS 335991 definition and cross‑references. ²
• GSA Acquisition.gov — Product and Service Code (PSC) Manual (April 2025). ³
• U.S. Census Bureau — Implementation of the 2022 NAICS (timeline and scope). ⁴

References

1. U.S. Census Bureau, North American Industry Classification System (NAICS) main page. https://www.census.gov/naics/
2. U.S. Census Bureau, NAICS 335991 (search result for 2022 vintage). https://www.census.gov/naics/?input=335991&year=2022
3. General Services Administration, Product and Service Code (PSC) Manual, April 2025. https://www.acquisition.gov/sites/default/files/manual/PSC%20Manual%20April%202025.pdf
4. U.S. Census Bureau, The Census Bureau’s Implementation of the 2022 NAICS (timeline and adoption). https://www.census.gov/library/reference/code-lists/naics/2022/implementation-timeline.html