Frequently Asked Questions

What is a CAIS?

Chemical agent identification sets (CAIS), also known as war gas identification sets, were produced between the 1930s and 1960s for use by the military to train Soldiers safely to identify, handle and decontaminate chemical agents.  The sets consist of small quantities of various chemical agents placed in glass ampoules, vials, or bottles, then packed in metal shipping containers or wooden boxes.  CAIS should be considered dangerous and should not be touched. 

It is important to know:

  • The chemicals that CAIS may contain can cause serious injury, even if solidified.  
    • Seek immediate medical attention if you believe that you have been exposed to chemical agents.
    • CAIS have been found on the surface and buried underground at active and former military installations, particularly in areas used for training.
    • CAIS are dangerous and should not be touched.

What do CAIS look like?

CAIS consist of small quantities of various dilute chemical agents in glass vials and bottles that were packed in metal shipping containers or wooden boxes. Unlike most CAIS, two sets–CAIS K941, toxic gas set M-1; and CAIS K942, toxic gas set M-2/E11 contain a relatively large quantity of chemical agent (mustard). Because of the large quantity of mustard agent, DoD considers these two CAIS more hazardous than all other CAIS.

CAIS may appear to be brand new or old, rusted, and/or damaged. Depending upon the chemical agent involved and the environment (e.g., heat, sunlight, length of burial) a CAIS experienced, the color of the chemical agent can vary drastically.

CAIS may be encountered in their original storage and shipping containers (metal containers or wooden boxes) or the CAIS glass vials and bottles may be found loose.

What should I do if I find or think I have found a CAIS?

In the past (prior to the early-1970s), one of the approved procedures for disposing of CAIS was burial on training ranges or areas. When buried, CAIS were either buried in their original metal or wooden storage and shipping containers–called PIGS–or loose. Normally, CAIS vials were broken before burial and decontaminant was used to neutralize any chemical agent present.

If you discover or think you may have discovered a CAIS, either in a storage or shipping container, or loose vials or bottles, contact local law enforcement (call 911). Local law enforcement will contact military experts for assistance.

What would Department of Defense do with a CAIS?

  • Packaging – Using personal protection equipment (e.g., protective clothing, equipment, rubber gloves), trained personnel seal the CAIS in plastic and place it in a sealed container. If a vial or bottle is broken and chemical agent was released to the soil, any chemical agent contaminated soil is removed, packaged, and properly disposed at a predetermined treatment storage disposal facility (TSDF).
  • Assessment – Personnel (military or civilian) who are trained in the identification and handling of chemical agents will assess suspect CAIS. This assessment will both determine whether the suspect item is a CAIS and evaluate its condition. After assessment, response personnel determine the best method for disposal of the CAIS or unknown item.
  • Storage – When necessary, CAIS may be packaged and stored on site until their final disposition can be arranged. When stored on site, CAIS are placed in an Interim Holding Facility (IHF). The IHF’s location meets established safety criteria, and is approved by the Department of Defense Explosives Safety Board.
  • Disposition – Currently, the Army destroys CAIS using specialized equipment. For individual vials, the Army uses the Single CAIS Access and Neutralization System SCANS. When a large quantity of CAIS are to be destroyed, the Army uses Rapid Response System (RRS).  If not destroyed onsite, CAIS may be taken to an appropriately permitted TSDF for disposal. 
  • Transportation – CAIS transported over public highways are packaged and transported per Department of Transportation requirements. These requirements specify proper packaging, given the chemical agent and quantity present, and require the transport vehicle to be properly placarded (signs indicating the type of material present and the general hazard). If CAIS are destroyed on site, any secondary wastes are similarly packaged and transported to a TSDF for disposal.

What is Chemical Warfare Materiel?

Chemical Warfare Materiel has been defined by the Army as an item configured as a munition containing a chemical substance that is intended to kill, seriously injure, or incapacitate a person.  The United States established a program to develop and produce chemical munitions when it entered World War I in 1917.  Following World War I, the United States continued to develop chemical warfare agents and train troops in the use of chemical warfare materiel.  These training programs were expanded during World War II.  Development continued with the capture of enemy chemical warfare agents and later into the Cold War period of United States history.  Chemical warfare materiel can be generally grouped into three main categories: chemical munitions, Chemical agent identification sets (CAIS), and bulk chemical warfare materiel containers.  Due to their hazards, CAIS are also handled like chemical warfare materiel.  More recently, the definition of chemical warfare materiel has changed, and it now does not include: riot control agents; chemical herbicides (plant/weed killers); smoke and flame producing items; or soil, water, or other debris contaminated with chemical agents.