White Phosphorus

Spatial analysis of the effects of white phosphorus wedges landing on the UNRWA School in Beit Lahia, Gaza, 17 Jan 2009

This investigation is concerned with the behaviour and effects of airburst white phosphorus munitions in densely populated areas. Its outcome is a technical interactive report titled “The Use of White Phosphorus Munitions in Urban Environments: An Effects-Based Analysis“. The report was produced for Attorneys Michael Sfard and Emily Schaeffer who, with the human rights organization Yesh Gvul, have submitted a petition to Israel’s High Court of Justice calling for the prohibition of the use of this munition in urban environments by the Israel Defence Forces. The report was presented publicly for the first time in the UN Office at Geneva, in the frame of the advocacy event on incendiary weapons held by Human Rights Watch, during the annual Meeting of the CCW States Parties (12-16 November 2012).

M825 WP
Among the variety of white phosphorus munitions that exist in military arsenals, this study focuses on the M825 WP projectile. Typically fired from a 155mm howitzer this projectile has a range of up to 18 kilometers. At a pre-calculated height above its target, a charge at the front of the shell is activated and the projectile separates into two parts releasing the 116 white phosphorus soaked felt wedges it contains. Once released, the wedges descend onto the ground in an elliptical pattern of up to 250 meters in the long axis. 

Immediately upon coming into contact with oxygen, white phosphorus will begin to burn and produce a dense white smoke. Because of this smoke producing effect, white phosphorus munitions are frequently used as obscurants to screen movements of troops. A secondary use and effect of the projectile is as an incendiary device – igniting fires in areas where they are deployed. In recent history M825 WP projectile has been used by the United States Military in 2004 during operations in Fallujah and by the Israel Defense Force in 2009 during Operation Cast Lead in Gaza – both densely populated urban environments. Following these operations, both of which saw significant civilian casualties, concerns have been raised around the legality and the humanitarian implications surrounding the use of white phosphorus. There are three distinct ways in which the M825 WP projectile can cause harm to civilians. Direct contact with the felt wedges can cause severe injury, penetrating clothing and burning directly through skin and bone. The smoke is also toxic and can cause severe irritation to lungs if inhaled directly. By far the most dangerous aspect of this projectile however is its incendiary effect as wedges become ignition sources that can start fires throughout areas where projectiles are deployed. Civilians frequently become trapped and die in these fires.

Ultimately, the diffuse nature of this projectile, which can impact an area of up to 30,000 square meters, makes it impossible for deploying forces to distinguish between legitimate military targets and civilian populations or objects. Airburst white phosphorus munitions are thus considered by many to be an indiscriminate weapon.

Effects-Based Analysis
Our work focuses on an Effects-Based Analysis devoted to modeling the behaviour of the M825 WP projectile as it interacts with a series of typical urban environments, in an effort to quantify and document its effects, as well as the resulting civilian damage that can be expected. In addition to military manuals and expert testimony (particularly that of weapon expert Chris Cobb-Smith), a major source of information for this research is the existing visual documentation of the use of airburst white phosphorus  – from news footage, reporters’ photographs or witness videos. With the help of 3D-modeling software, spatial data is extracted from still and moving images in an effort to reconstruct both specific events and general behaviour of the projectile. This data is ultimately integrated into a parametric model that simulates the burst of an M825 WP projectile over typical urban environments, and allows to analyse its effects.

Considering that current international law falls short of protecting civilians against the use of airburst white phosphorus munitions, the ultimate goals of this research are: to present publicly the impact of this projectile on civilian life; and to demonstrate the need to amend international law so as to ban its use in densely populated areas.


Video-analysis. Coverage Area of a M825 WP round fired in Gaza, 11 January 2009 (footage: Al-Jazeera)

HoB-1 Methodology for the calculation of the Height of Burst (HoB) of the projectile on a still photograph, using reference heights of surrounding architectural features.


Photographic Analysis. Location: Gaza. Date: January 12, 2009. Author: David Silverman. Owner: Getty Images


Photographic Analysis. Location: Gaza. Date: January 4, 2009. Author: Uriel Sinai. Owner: Getty Images