Related Rule
United States of America
Practice Relating to Rule 30. Persons and Objects Displaying the Distinctive Emblem
The US Soldier’s Manual (1984) instructs members of armed forces not to fire on persons and objects displaying the red cross or red crescent emblem. 
United States, Your Conduct in Combat under the Law of War, Publication No. FM 27-2, Headquarters Department of the Army, Washington, November 1984, p. 7.
The US Manual for Military Commissions (2010), Part IV, Crimes and Elements states:
The term “protected property” means any property specifically protected by the law of war (including … hospitals, and places where the sick and wounded are collected) … [and] includes objects properly identified by one of the distinctive emblems of the Geneva Conventions”. 
United States, Manual for Military Commissions, published in implementation of Chapter 47A of Title 10, United States Code, as amended by the Military Commissions Act of 2009, 10 U.S.C, §§ 948a, et seq., 27 April 2010, § 1(a)(3), p. IV-1.
The US Military Commissions Act (2006), passed by Congress following the Supreme Court’s decision in Hamdan v. Rumsfeld in 2006, amends Title 10 of the United States Code as follows:
§ 950v. Crimes triable by military commissions
“(a) DEFINITIONS AND CONSTRUCTION.—In this section:
“ …
“(3) PROTECTED PROPERTY.—The term ‘protected property’ means property specifically protected by the law of war (such as buildings dedicated to religion, education, art, science or charitable purposes, historic monuments, hospitals, or places where the sick and wounded are collected), if such property is not being used for military purposes or is not otherwise a military objective. Such term includes objects properly identified by one of the distinctive emblems of the Geneva Conventions, but does not include civilian property that is a military objective. 
United States, Military Commissions Act, 2006, Public Law 109-366, Chapter 47A of Title 10 of the United States Code, 17 October 2006, p. 120 Stat. 2625, § 950v(a)(3).
The US Military Commissions Act (2009) amends Chapter 47A of Title 10 of the United States Code as follows:
§ 950p. Definitions; construction of certain offenses; common circumstances
“(a) DEFINITIONS.—In this subchapter:
“ …
“(3) The term ‘protected property’ means any property specifically protected by the law of war, including … hospitals, and places where the sick and wounded are collected … [and] includes objects properly identified by one of the distinctive emblems of the Geneva Conventions. 
United States, Military Commissions Act, 2009, § 950p(a)(3).