United States Army Chemical Biological Radiological and Nuclear School (USACBRNS)
Active	1918 – present
Country	United States
Branch	United States Army
Type	TRADOC
Garrison/HQ	Fort Leonard Wood
Motto(s)	Elementis regamus proelium (Let Us Rule the Battle by Means of the Elements or We rule the battle through the elements)
Colors	Cobalt Blue and Gold
Mascot(s)	Dragon
Commanders
33rd Chief of Chemical/ Commandant	Colonel Alexander C. Lovasz
Regimental Chief Warrant Officer	Chief Warrant Officer 4 Matthew D. Chrisman
Regimental Command Sergeant Major	Command Sergeant Major David C. Henderson
Notable commanders	LTG Thomas W. Spoehr, LTG Leslie Smith, MG Peggy Combs, LTG Maria Gervais, MG James Bonner, MG Daryl O. Hood, BG Sean Crockett

The United States Army CBRN School (USACBRNS), located at Fort Leonard Wood, Missouri, is a primary American training school specializing in military Chemical, Biological, Radiological, and Nuclear (CBRN) defense.^[1] Until 2008, it was known as the United States Army Chemical School.

In accordance with U.S. Federal Law, Fort Leonard Wood, Missouri is designated as the central location for all of the Department of Defense's CBRN Operations Training, and is home to the U.S. Army's Chemical Corps Regiment. It was moved from Fort McClellan Alabama after the base was closed by the Defense Base Closure and Realignment Commission (BRAC) in 1999.

The Army CBRN School provides numerous courses for Commissioned Officers, Non-Commissioned Officers and Initial Entry Soldiers. Numerous international organisations also send students to train at the CBRN School. Additionally, the US Air Force, US Navy, US Coast Guard and US Marine Corps also maintain training elements at Fort Leonard Wood, in partnership with the Army, to train their personnel in CBRN operations.

Fort Leonard Wood and the United States Army CBRN School have facilities, in which to conduct training, such as Chemical Defense Training Facility (or CDTF) where military students from across the globe train and become familiar with nerve agents in realistic scenarios, and conduct training with radiological isotopes and inert biological agents. The Edwin R. Bradley Radiological Teaching Laboratories is one of the few radiological teaching laboratories licensed by the NRC in the Department of Defense. It provides a variety of training in radiological and nuclear defense under the supervision of credentialed scientists.

The newest facility at the CBRN School is the Lieutenant Joseph Terry CBRN Training Facility. Opened in November 2007, the 1LT Joseph Terry Chemical, Biological, Radiological, Nuclear (CBRN) Responder Training Facility occupies approximately 22.5 acres (91,000 m²) and provides a state-of-the-art^{[peacock prose]} CBRN Responder Training Campus for Inter-Service and other Agencies as requested. The US Army CBRN School is the lead for all DOD CBRN Response Training. This facility provides unmatched^{[peacock prose]} training opportunities in the fields of CBRN Consequence Management, Hazardous Materials Incident Response, Realistic training venues and other CBRN Response arenas as required. The CBRN School also provides training in Sensitive Site Assessment and Exploitation.

In addition to training, the CBRN School also develops doctrine for Operations, researches and develops materiel requirements, and conducts joint service experimentation as the Joint Combat Developer for the Department of Defense's Chemical and Biological Defense Program.

On 11 January 2008, The U.S. Army Chemical School was renamed as The U.S. Army Chemical, Biological, Radiological and Nuclear School (USACBRNS). The name change was to encompass, in the title of the school the wide range of training and expertise maintained by the U.S. Army Chemical Corps.

As of August 31, 2024, the Commandant of the U.S. Army CBRN School is Colonel Alexander C. Lovasz. The Assistant Commandant is Colonel Sedrick L. Jackson. The Regimental Command Sergeant Major is CSM David C. Henderson. The Regimental Chief Warrant Officer is CW4 Matthew D. Chrisman.^[2]

		Name	Photo	Term Began	Term Ended	Y	M	D	Reason
Director of Chemical Warfare Service
-	MG	William L. Sibert		17 May 1918	1 Mar 1920	1	9	14	Resigned	1884 (USMA)
Chief of the Chemical Warfare Service
1.	MG	Amos A. Fries		1 Jul 1920 (16 Jul 1920)	27 Mar 1929	8	8	12	Relieved	1898 (USMA)
2.	MG	Harry L. Gilchrist		28 Mar 1929	27 Mar 1933	4	-	-	Relieved	1900
3.	MG	Claude E. Brigham		9 May 1933 (24 May 1933)	23 May 1937	4	-	-	Relieved	1901 (USMA)
4.	MG	Walter C. Baker		24 May 1937	30 Apr 1941	3	11	7	Retired	1901
5.	MG	William N. Porter		31 May 1941	30 May 1945	4	-	-	Relieved	1910
*	MG	William N. Porter		31 May 1945	10 Nov 1945	-	5	11	-	-
*	BG	Alden H. Waitt		10 Nov 1945	29 Nov 1945	-	-	20	-	-
6.	MG	Alden H. Waitt		29 Nov 1945	20 Aug 1946	-	8	23	Retired	1920
Chief of the Chemical Corps
6.	MG	Alden H. Waitt		20 Aug 1946	30 Sept, 1949	3	1	11	Retired	1920
7.	MG	Anthony C. McAuliffe		1 Oct 1949	1950				Relieved	1919 (USMA)
Chief Chemical Officer
7.	MG	Anthony C. McAuliffe		1950	31 Jul 1951				Relieved	1919 (USMA)
8.	MG	Egbert F. Bullene		25 Aug 1951	31 Mar 1954	2	6	25	Retired	1917 (USNA)
9.	MG	William M. Creasy		7 May 1954	31 Aug 1958	4	3	25	Retired	1926 (USMA)
10.	MG	Marshall Stubbs		1 Sept, 1958	31 Jul 1962	3	11	-	Relieved	1929 (USMA)
Chief of Chemical
24.	BG	Thomas W. Spoehr		29 Jun 2006
25.	BG	Leslie C. Smith			10 Aug 2010					1983 (ROTC)
26.	COL	Vance P. Visser		10 Aug 2010	24 Aug 2012					1984 (ROTC)
27.	BG	Peggy C. Combs		7 Sept, 2012	5 June 2014					1985 (ROTC)
28.	BG	Maria R. Gervais		5 June 2014	26 May 2016					1987 (ROTC)
29.	BG	James E. Bonner		26 May 2016	6 July 2017					1988 (ROTC)
30.	BG	Antonio (Andy) Munera		29 June 2017	25 April 2019					1991 (ROTC)
31.	BG	Daryl O. Hood		25 April 2019	4 June 2021					1991 (ROTC)

• Army Gas School
• Human experimentation in the United States

• U.S. Army CBRN School official website.
• Fort Leonard Wood Army Training Center official website.