PSC AH51: Natural Resources and Environment R&D Services; Other Natural Resources; Basic Research
AH51 is the product and service code (PSC) federal agencies use for “Natural Resources and Environment R&D Services; Other Natural Resources; Basic Research”, in the “R&D – Other Pollution” group. Here are the contracts open under it now, the NAICS codes it pairs with, and who buys and wins this work.
- Open contracts now
- 0
- Federal contract spending, FY2025
- $4.8 million
- Share of contract dollars to small businesses, since FY2024
- 26%
Open count as of Nov 6, 2026, 8:23 PM ET. The search counts live, so its total can differ by a notice or two.
Where AH51 sits in the PSC Manual
- Category: Research and Development
- Group AH: Natural Resources and Environment R&D Services
- Group AH5: R&D – Other Pollution
- Code AH51: Natural Resources and Environment R&D Services; Other Natural Resources; Basic Research
NAICS codes used with PSC AH51
The NAICS code on a contract sets the size standard for who counts as small. These are the codes agencies pair with AH51 most often:
| NAICS | Industry | Spent, last 3 years | Open with PSC AH51 |
|---|---|---|---|
| 541715 | Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology) | $22.8 million | — |
| 611310 | Colleges, Universities, and Professional Schools | $631,924 | — |
| 334513 | Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables | $159,407 | — |
| 541620 | Environmental Consulting Services | $91,090 | — |
| 813312 | Environment, Conservation and Wildlife Organizations | $88,081 | — |
| 541720 | Research and Development in the Social Sciences and Humanities | $43,951 | — |
Open contracts under each code, with any PSC: NAICS 541715 · NAICS 611310 · NAICS 334513 · NAICS 541620 · NAICS 813312 · NAICS 541720
Who buys under PSC AH51
Agencies with the most contract dollars under AH51 over the last three fiscal years, per USAspending.gov. Each name links to that agency's open contracts and buying history:
| Agency | Obligated |
|---|---|
| Department of the Army | $17.8 million |
| Environmental Protection Agency | $4 million |
| U.S. Geological Survey | $1.2 million |
| National Aeronautics and Space Administration | $449,389 |
| Smithsonian Institution | $180,000 |
| Department of the Air Force | $88,081 |
| Forest Service | $71,031 |
Federal spending under PSC AH51 by year
| Fiscal year | Contract obligations |
|---|---|
| FY2024 | $14.3 million |
| FY2025 | $4.8 million |
| FY2026 (incomplete) | $4.7 million |
Headline figures use FY2025, the last complete year. FY2026 is still incomplete and will rise until about early January 2027 as Defense data arrives: USAspending.gov publishes Defense contracts 90 days after they're signed. FY2027 began October 1, 2026; it's left out until Defense data for it starts to arrive.
Who wins PSC AH51 contracts
| Company | Obligated, last 3 years |
|---|---|
| Trustees of the Colorado School of Mines | $4.3 million |
| Specpro Sustainment and Environmental, LLC | $2.5 million |
| Arizona State University | $1.8 million |
| Geosyntec Consultants, Inc. | $1.7 million |
| Specpro Professional Services, LLC | $1.5 million |
| Brown University | $1 million |
| Case Western Reserve University | $948,356 |
| Northeastern University | $903,477 |
| University of Miami | $738,259 |
| Conservation Science Partners, Inc. | $687,716 |
Linked names have a FedReady profile, which shows the NAICS codes a business is registered as small under. Most large companies have none.
Large prime contractors (companies that hold the contract with the agency) subcontract part of their work to small businesses. See which primes subcontract, by NAICS code.
Research PSC AH51 work
By the NAICS codes this work goes with, the one with the most spending first: who won recently, contracts ending soon, agencies' planned buys and the large primes that subcontract it, nationwide. Each code shows only the pages that exist for it:
- 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology): who won recently · contracts ending in the next 12 months · planned buys · large primes that subcontract
- 611310 Colleges, Universities, and Professional Schools: large primes that subcontract
- 334513 Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables: who won recently · contracts ending in the next 12 months · planned buys · large primes that subcontract
Related PSC codes
- AH52 Natural Resources and Environment R&D Services; Other Natural Resources; Applied Research
- AH53 Natural Resources and Environment R&D Services; Other Natural Resources; Experimental Development
- AH54 Natural Resources & Environment R&D SVCS; Other Natural Resources; R&D Administrative Expenses
- AH55 Natural Resources & Environment R&D SVCS; Other Natural Resources; R&D Facilities & Maj Equip
- AH56 R&D – Other Pollution – MGMT Sup
- AH57 R&D – Other Pollution – Comercliz
Frequently asked questions
What is PSC AH51?
AH51 is the research and development code in the federal Product and Service Code (PSC) Manual named “Natural Resources and Environment R&D Services; Other Natural Resources; Basic Research”, under AH (Natural Resources and Environment R&D Services) and AH5 (R&D – Other Pollution). Agencies put a PSC on every contract to record what they bought.
What is the difference between a PSC and a NAICS code?
A PSC describes what the government is buying. A NAICS code describes the industry of the business doing the work, and it sets the SBA size standard for small business set-asides. Every contract notice has both.
Which NAICS code goes with PSC AH51?
Most federal contract dollars under PSC AH51 go with NAICS 541715 (Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)), according to USAspending.gov. The contracting officer picks the NAICS code for each solicitation, so check the notice.
How do I find contracts that use PSC AH51?
Contract opportunities are posted on SAM.gov with their PSC and NAICS codes. FedReady can match new ones to your business and email you, free.
Keep going
Sources: SAM.gov Contract Opportunities, USAspending.gov and the PSC Manual. How we count.