1.1. White phosphorus, its harmful effects, and its military uses

White phosphorus is a highly flammable chemical substance made from a common allotrope of phosphorus. It ignites spontaneously upon contact with air, producing a dense white smoke.

White phosphorus is considered a toxic substance¹, capable of causing severe injuries to internal organs when absorbed through skin, ingested, or to lesser degree when inhaled. When burning particles of white phosphorus come into contact with skin, they produce thermal and chemical burns. Because of its high solubility in fat, white phosphorus has the potential for deep dermal penetration and can rapidly burn exposed body areas down to the bone². Burn wounds can also re-ignite when bandages are removed and burnt areas re-exposed to oxygen.

Within military context, white phosphorus (WP) can be found in a variety of munitions, such as grenades, mortars, and artillery shells. These munitions are used for four distinct purposes³:

• Illumination - The bright white light created by the burning WP can be used to illuminate large areas at night.
• Signaling - The dense smoke produced by WP can be used to signal a target.
• Screening - WP smoke can also be used to create a thick smoke-screen to hide the movement of people and vehicles in open or built environments.
• Incendiary - WP munitions can be used to set targets and combat areas on fire.

Depending on the situation and objectives, military forces may choose to deploy a particular WP ammunition because of its specific design and characteristics, rather than another. Regardless of the primary military purpose for using a WP ammunition, a range of secondary effects can be generated that are specific to the properties of white phosphorus itself. In particular, when WP munitions are deployed in urban environments for signaling or screening purposes, they can produce incendiary effects that may harm civilian persons and objects. These secondary effects are the primary focus of this report.

1.2 Objectives of the report

The report presents an Effect-Based Analysis (EBA)⁴ of the American-made M825 WP Smoke projectile.

The M825 WP has been used in urban contexts during the assaults on Fallujah (by the United States military in 2004) and Gaza (by the Israel military in 2009). Although primarily designed to produce smoke-screens, the secondary effects of WP munitions have been widely acknowledged and documented. These include: ignition of multiple fires in the impact area, direct strike on civilians by falling projectile debris, and long-term contamination of the environment⁵.

The main objectives of this report are to analyze the incendiary effects of the M825 WP projectile when deployed in urban environments, and to evaluate the civilian exposure that may be expected in such scenarios.

Effects in urban environments are due to specific characteristics of, on the one hand, the projectile itself, and on the other hand, the built environment impacted. Therefore, the methods employed in this report combine ballistic simulation with spatial analysis and urban reconstruction. After detailing the characteristics and the functioning of the M825 WP (Section 2), the report analyzes the interplay between the projectile and a given built environment at both the urban scale (Section 3) and the architectural scale (Section 4). The specific objectives of the report are:

• To evaluate the Coverage Area of the M825 WP projectile.
• To identify the range of parameters, controllable and uncontrollable, at play when the projectile is deployed over typical urban environments.
• To catalog types of damage to objects and persons in urban contexts and to quantify civilian exposure across a range of contexts.

1.3 Sources of information

Three principal sources of information have been used in the formulation of this report.

• Military field manuals and manufacturer documentation of the M825 WP projectile⁶.
• Photographic and video documentation of M825 WP deployment and its subsequent effects, in the cases of Fallujah (2004) and Gaza (2009).
• Reports of post-combat site surveys in both cities conducted by independently commissioned non-governmental organizations⁷.
• Expertise on the military use of white phosphorus by Chris Cobb-Smith, weapons expert and safety and security advisor to the International News Safety Institute.