CBRN defense in the context of "Military construction"

Military engineering is loosely defined as the art, science, and practice of designing and building military works and maintaining lines of military transport and military communications. Military engineers are also responsible for logistics behind military tactics. Military engineering is a predecessor of civil engineering, currently differs in its applications across disciplines and specialized work. In the 20th and 21st centuries, military engineering also includes CBRN defense and other engineering disciplines such as mechanical and electrical engineering techniques.

According to NATO, "military engineering is that engineer activity undertaken, regardless of component or service, to shape the physical operating environment. Military engineering incorporates support to maneuver and to the force as a whole, including military engineering functions such as engineer support to force protection, counter improvised explosive devices, environmental protection, engineer intelligence and military search. Military engineering does not encompass the activities undertaken by those 'engineers' who maintain, repair and operate vehicles, vessels, aircraft, weapon systems and equipment."

Chemical warfare (CW) involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from nuclear warfare, biological warfare and radiological warfare, which together make up CBRN, the military acronym for chemical, biological, radiological, and nuclear (warfare or weapons), all of which are considered "weapons of mass destruction" (WMDs), a term that contrasts with conventional weapons.

The use of chemical weapons in international armed conflicts is prohibited under international humanitarian law by the 1925 Geneva Protocol and the Hague Conventions of 1899 and 1907. The 1993 Chemical Weapons Convention prohibits signatories from acquiring, stockpiling, developing, and using chemical weapons in all circumstances except for very limited purposes (research, medical, pharmaceutical or protective).

The M1 Abrams (/ˈeɪbrəmz/) is a third-generation American main battle tank designed by Chrysler Defense (now General Dynamics Land Systems) and named for General Creighton Abrams. Conceived for modern armored ground warfare, it is one of the heaviest tanks in service at nearly 73.6 short tons (66.8 metric tons). It introduced several modern technologies to the United States armored forces, including a multifuel turbine engine, sophisticated Chobham composite armor, a computer fire control system, separate ammunition storage in a blowout compartment, and NBC protection for crew safety. Initial models of the M1 were armed with a 105 mm M68 gun, while later variants feature a license-produced Rheinmetall 120 mm L/44 designated M256.

The M1 Abrams was developed from the failed joint American-West German MBT-70 project that intended to replace the dated M60 tank. There are three main operational Abrams versions: the M1, M1A1, and M1A2, with each new iteration seeing improvements in armament, protection, and electronics.

Radiological warfare is any form of warfare involving deliberate radiation poisoning or contamination of an area with radioisotopes, but without the use of nuclear weapons. While radiological weapons were researched and in some cases tested during the Cold War, there is no evidence any military has ever deployed operational radiological weapons, although they have been used for assassination.

Nuclear warfare, both via fission and fusion weapons, creates radioisotopes in the form of fission products and neutron-activated surface material. This fallout is incorporated into military planning. Neutron bombs are designed to maximize the lethal radiation area and minimize the blast. These uses are generally not considered direct radiological warfare, but salted bombs, which maximize radioisotope production in a nuclear blast, are.