SIC 4581 — Airports, Flying Fields, and Airport Terminal Services
Official OSHA SIC Manual Definition
Establishments primarily engaged in operating and maintaining airports and flying fields; in servicing, repairing (except on a factory basis), maintaining, and storing aircraft; and in furnishing coordinated handling services for airfreight or passengers at airports. This industry also includes private establishments primarily engaged in air traffic control operations. Government air traffic control operations are classified in Public Administration, Industry 9621. Aircraft modification centers and establishments primarily engaged in factory type overhaul of aircraft are classified in Manufacturing, Major Group 37, and flying fields maintained by aviation clubs are classified in Services, Industry 7997.
Description & Classification
SIC code 4581 representing 'Airports, Flying Fields, and Airport Terminal Services' is an industry category in the Standard Industrial Classification (SIC) system under U.S. OSHA and Federal procurement registers.
Modern NAICS Crosswalk
Trace the modern equivalent classifications in the 2022 North American Industry Classification System (NAICS) database:
- NAICS 488111 - Air Traffic Control (via SIC1987:4581→NAICS1997:488111→2002:488111→2007:488111→2012:488111→2017:488111→2022:488111)
- NAICS 238990 - All Other Specialty Trade Contractors (via SIC1987:4581→NAICS1997:56172→2002:238990→2007:238990→2012:238990→2017:238990→2022:238990)
- NAICS 561720 - Janitorial Services (via SIC1987:4581→NAICS1997:56172→2002:561720→2007:561720→2012:561720→2017:561720→2022:561720)
- NAICS 488119 - Other Airport Operations (via SIC1987:4581→NAICS1997:488119→2002:488119→2007:488119→2012:488119→2017:488119→2022:488119)
- NAICS 488190 - Other Support Activities for Air Transportation (via SIC1987:4581→NAICS1997:48819→2002:488190→2007:488190→2012:488190→2017:488190→2022:488190)
Classification Details
| SIC Code | 4581 |
|---|---|
| Industry Title | Airports, Flying Fields, and Airport Terminal Services |
| Division | Division E: Transportation, Communications, Electric, Gas, and Sanitary Services |
| Major Group | Major Group 45: Transportation by Air |
| JSON Endpoint | View as JSON · API → |
| Source / Verified | US Census 1987 SIC Concordance / 2026-08-08 |
SIC vs NAICS Compliance & Common Mismatches
Legacy SIC code 4581 classifies commercial operations based on primary end-product or service output under the 1987 federal framework. In contrast, modern 2022 NAICS codes group establishments based on production process inputs.
When submitting public disclosures to SEC EDGAR or determining OSHA workplace safety log recordkeeping exemptions (29 CFR Part 1904), rely strictly on the official OSHA 4-digit SIC classification rather than an automated commercial translation.
💡 Expert Guidance: SIC to NAICS Conversion
Common Compliance Mistake: Many contractors and B2B analysts confuse legacy 4-digit SIC codes like 4581 with modern 6-digit NAICS codes. Ensure that you use the correct active 2022 NAICS code (e.g. from the crosswalk below) when submitting representations on SAM.gov, as federal contracting officers only accept modern NAICS codes.
Related Pages & Tools
Further regulatory reference links for legacy SIC code 4581:
- SIC Codes Complete Compliance Guide — Detailed history and active legal applications of the SIC classification framework.
- Why Legacy SIC Codes Persist Guide — How credit systems and the SEC still rely on SIC metadata.
- SIC ↔ NAICS Crosswalk Tool — Trace industrial code conversions dynamically.
- SIC 4581 to NAICS Crosswalk — Bidirectional mapping to modern NAICS codes (Airports, Flying Fields, and Airport Terminal Services).
- SIC Major Group 45 Hub — View other legacy industries in this business division.
Frequently Asked Questions (FAQ)
What industry sector is represented by legacy SIC code 4581? ▾
Legacy SIC code 4581 represents 'Airports, Flying Fields, and Airport Terminal Services', categorized under Division Division E: Transportation, Communications, Electric, Gas, and Sanitary Services and Major Group Major Group 45: Transportation by Air. The Standard Industrial Classification (SIC) system was developed in the late 1930s.
What is the modern 2022 NAICS equivalent for legacy SIC 4581? ▾
Legacy SIC code 4581 maps to the modern 2022 NAICS industry classifications: NAICS 488111 (Air Traffic Control), NAICS 238990 (All Other Specialty Trade Contractors), NAICS 561720 (Janitorial Services), NAICS 488119 (Other Airport Operations), NAICS 488190 (Other Support Activities for Air Transportation). Mappings are resolved transitively across successive updates to handle splits.
Why do credit agencies and banks still reference legacy SIC code 4581? ▾
Registries like Dun & Bradstreet, insurance underwriters, and private platforms retain SIC code 4581 because their historical financial risk data and scoring models are indexed using the legacy 4-digit SIC framework.
Does the SEC EDGAR system allow searching public filings by SIC 4581? ▾
Yes. The SEC Division of Corporation Finance assigns a primary 4-digit SIC code to public companies. You can search the EDGAR database using SIC code 4581 to group reporting peer firms.
How do OSHA safety recordkeeping rules apply to SIC code 4581? ▾
Under 29 CFR Part 1904 safety regulations, OSHA references legacy SIC codes including 4581 to determine if a physical establishment is required to maintain daily injury logs (Form 300) or is partially exempt.
What is the structural difference between SIC 4581 and NAICS codes? ▾
SIC code 4581 classifies establishments based on their final product output or market destination (what they sell), while modern NAICS codes classify them based on production processes and inputs (how they work).
What are the typical business activities classified under legacy SIC 4581? ▾
Typical business activities classified under legacy SIC 4581 are the operations associated with 'Airports, Flying Fields, and Airport Terminal Services'. Mapped modern NAICS codes can be referenced for specific current examples.
Is legacy SIC code 4581 uniform across all 50 U.S. states? ▾
Yes, the Standard Industrial Classification (SIC) system, including code 4581, was published as a federal standard and remains uniform nationwide. It is still referenced by various state workers' compensation boards and departments of labor.
Sources & References
- U.S. Department of Labor (OSHA): OSHA Standard Industrial Classification (SIC) Manual — Code 4581
- U.S. Census Bureau: 1987 SIC to 2022 NAICS Concordance Tables
- Federal Reserve Board: Industrial Production & Capacity Utilization Classifications
- Internal Revenue Service (IRS): Schedule C Principal Business Activity (PBA) Industry Concordance
- Office of Management and Budget (OMB): Standard Industrial Classification Systems Governance