---
kind: "section"
citation: "10 U.S.C. § 6121"
title: "10"
title_heading: "Armed Forces"
number: "6121"
heading: "Testing of nuclear weapons"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/10/6121"
units:
  - "Subtitle A — General Military Law"
  - "Part VI — Elements of Department of Defense and Other Matters"
  - "Subpart B — Atomic Energy Defense"
  - "Chapter 602 — Nuclear Weapons Stockpile Matters"
  - "Subchapter I — Stockpile Stewardship and Weapons Production"
---

# §6121. Testing of nuclear weapons

- (a) **Underground Testing.—** No underground test of nuclear weapons may be conducted by the [United States](/usc/10/101.md?p=a-1) after September 30, 1996, unless a foreign [state](/usc/10/4951.md?p=4) conducts a nuclear test after this date, at which time the prohibition on [United States](/usc/10/101.md?p=a-1) nuclear testing is lifted.
- (b) **Atmospheric Testing.—** None of the funds appropriated pursuant to the National Defense Authorization Act for Fiscal Year 1994 (Public Law 103–160; 107 Stat. 1547) or any other Act for any fiscal year may be available to maintain the capability of the [United States](/usc/10/101.md?p=a-1) to conduct atmospheric testing of a nuclear weapon.

## Source credit

(Added Pub. L. 119–60, div. C, title XXXI, § 3111(a), Dec. 18, 2025, 139 Stat. 1358.)

## Notes

### Editorial Notes

### References in Text

The National Defense Authorization Act for Fiscal Year 1994, referred to in subsec. (b), is Pub. L. 103–160, Nov. 30, 1993, 107 Stat. 1547. For complete classification of this Act to the Code, see Tables.

### Prior Provisions

Provisions similar to those in this section were contained in section 2530 of Title 50, War and National Defense, prior to repeal by Pub. L. 119–60, § 3111(b)(1).