26 July 2012: Syria’s chemical weapons and protection against their use: a brief overview

by John Hart

The escalation of the current conflict in Syria gives greater impetus to efforts to determine the fate of Syria’s weapon programmes and, in particular, its reported stocks of chemical weapons.

On 23 July 2012 a Syrian Ministry of Foreign Affairs (MFA) spokesman stated that his country possesses ‘weapons of mass destruction’ and, in particular, chemical weapons. He added: ‘All of these types of weapons are in storage and under security and the direct supervision of the Syrian armed forces and will never be used unless Syria is exposed to external aggression’.

There were indications that respirators (gas masks) have been distributed to some government forces. Syrian officials later appeared to backpedal as to whether they possess chemical weapons and are prepared to use such weapons.

General Adnan Silou, a high-ranking defector who reportedly oversaw the 2008 creation of emergency plans to help ensure that dangerous weapons remain under government control, confirmed earlier this month that the rebel forces were forming a special unit to secure chemical weapon sites. Silou stated that there are two principal chemical weapon stockpiles: warehouse 417 in eastern Damascus and warehouse 419 in the Homs area.

Chemical weapon agents are usually classified according to their principal effects. A typical classification of agents is: (a) blistering agents, (b) blood agents, (c) choking agents, (d) incapacitants, (e) nerve agents, (f) tear gas and (g) vomiting agents.

The chemical weapon agents that Syria is purported to possess are a blistering agent (sulphur mustard) and two nerve agents (sarin and a V-type agent, such as VX). Syrian authorities also possess riot control agents that could be lethal if misused. Historically, some industrial chemicals, such as phosgene and chlorine, have been used as choking agents. In recent years non-state actors have also attempted to use industrial chemicals to mount attacks (e.g. with chlorine in Iraq).

Chemical weapons are normally either a gas or fine droplets of liquid. Masks are effective against a range of aerosols, including toxic industrial chemicals. Protective shelters are effective—provided they are well constructed and remain uncompromised. Furthermore, after an attack (and depending on the nature of the weapon) effective decontamination can often be carried out using fairly readily available resources such as household detergents.

To summarize, chemical weapons can be highly lethal and can also have a powerful psychological effect. However, using them effectively is a specialized skill and the effects can be reduced by factors that the attacker cannot easily control.

Key technical factors informing the effects of chemical weapon use would include:

1. Whether such agents are used in the open or in enclosed spaces (or buildings);
2. The availability and quality of protective (individual or collective) measures;
3. Whether the people attacked are concentrated in a small area or dispersed over a wide area;
4. The availability and quality of decontamination equipment and material; and
5. Weather conditions, such as wind strength and direction.

Syria’s official statements can be seen as a reminder that it has both battlefield and strategic retaliatory capabilities available, adding to its deterrence capacity. Syrian chemical weapons would already be a factor in military planning, but widespread reporting of Syrian statements might complicate the domestic political calculation for states considering intervention (directly or by supporting others).

Given that the decision to use other types of heavy weaponry has already been taken, it is not clear how chemical weapons would enhance the capabilities of Syrian authorities vis-à-vis internal opponents, even in heavily built-up urban environments.

If chemical weapons use is alleged, it is important for appropriate technical experts to utilize validated sampling and analysis protocols, such as those developed by the Organisation for the Prohibition of Chemical Weapons (OPCW), and by the United Nations under the UN Secretary-General’s authority, to substantiate the allegations and, to the extent possible, support the determination of those responsible.


John Hart
is a Senior Researcher and Head of the Chemical and Biological Security Project of the SIPRI Arms Control and Non-proliferation Programme.
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