Related Rule
United States of America
Practice Relating to Rule 80. Booby-Traps
The US Air Force Pamphlet (1976) states:
Mines in the nature of booby-traps are frequently unlawfully used, such as when they are attached to objects under the protection of international law, e.g., wounded and sick, dead bodies and medical facilities. Also objectionable are portable booby-traps in the form of fountain pens, watches and trinkets which suggest treachery and unfairly risk injuries to civilians likely to be attracted to the objects. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 6-6(d).
The US Rules of Engagement for Operation Desert Storm (1991) states:
Booby traps may be used to protect friendly positions or to impede the progress of enemy forces. They may not be used on civilian personal property. They will be recovered or destroyed when the military necessity for their use no longer exists. 
United States, Desert Storm – Rules of Engagement, Pocket Card, US Central Command, January 1991, reprinted in Operational Law Handbook, International and Operational Law Department, The Judge Advocate General’s School, United States Army, Charlottesville, Virginia, 1995, pp. 8-7 and 8-8, § E.
The US Naval Handbook (1995) states:
Booby traps … are not unlawful, provided they are not designed to cause unnecessary suffering or employed in an indiscriminate manner… . Attaching booby traps to protected persons or objects, such as the wounded and sick, dead bodies, or medical facilities and supplies, is similarly prohibited. Belligerents are required to record the location of booby traps … in the same manner as land mines. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 9.6.
The US Naval Handbook (2007) states:
Booby traps and other delayed-action devices are not unlawful, provided they are not designed to cause unnecessary suffering or employed in an indiscriminate manner. … Attaching booby traps to protected persons or objects, such as the wounded and sick, dead bodies, or medical facilities and supplies, is similarly prohibited. Belligerents are required to record the location of booby traps and other delayed-action devices in the same manner as land mines. 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 9.6.
In 1976, during discussions in the Ad Hoc Committee on Conventional Weapons established by the CDDH, the United States welcomed proposals by other States to restrict the use of booby-traps and stated: “It was clearly desirable to place certain restrictions on the use of land-mines and other devices, including booby-traps.” It added that the United States “welcomed and shared the concern evidenced in the various proposals for the protection of the civilian population against the effects of mines and similar devices, and believed that those proposals constituted a good basis for the formulation of an effective agreement”. 
United States, Statement at the CDDH, Official Records, Vol. XVI, CDDH/IV/SR.29, 25 May 1976, p. 300, §§ 34–36.
Upon ratification of the 1980 Convention on Certain Conventional Weapons, the United States declared:
With reference to the scope of application defined in article 1 of the Convention, … the United States will apply the provisions of the Convention, Protocol I, and Protocol II to all armed conflicts referred to in articles 2 and 3 common to the Geneva Conventions for the Protection of War Victims of August 12, 1949. 
United States, Declaration made upon ratification of the Convention on Certain Conventional Weapons, 24 March 1995.
Upon ratification of the 1980 Convention on Certain Conventional Weapons, the United States stated:
The United States understands that article 6(1) of the Protocol II [to the Convention on Certain Conventional Weapons] does not prohibit the adaptation for use as booby-traps of portable objects created for a purpose other than as a booby-trap if the adaptation does not violate paragraph (1)(b) of the article. 
United States, Statements of understanding made upon ratification of the Convention on Certain Conventional Weapons, 24 March 1995.
Upon acceptance of the 1996 Amended Protocol II to the Convention on Certain Conventional Weapons, the United States declared:
(A) the prohibition contained in Article 7(2) of the Amended Mines Protocol [1996 Amended Protocol II to the Convention on Certain Conventional Weapons] does not preclude the expedient adaptation or adaptation in advance of other objects for use as booby-traps or other devices;
(B) a trip-wired hand grenade shall be considered a “boob-trap” under Article 2(4) of the Amended Mines Protocol and shall not be considered a “mine” or an “anti-personnel mine” under Article 2(1) or Article 2(3), respectively; and
(C) none of the provisions of the Amended Mines Protocol, including Article 2(5), applies to hand grenades other than trip-wired hand grenades. 
United States, Statements of understanding made upon acceptance of Amended Protocol II to the Convention on Certain Conventional Weapons, 24 May 1999, § (6)(A)–(C).