New DOD report explains M8A1
chemical alarms used in Gulf War

WASHINGTON, December 1, 1997 (GulfLINK) - The Defense Department has issued an information paper describing the M8A1, the chemical detection alarm of which 12,000 were used during the Gulf War.

The Office of the Special Assistant for Gulf War Illnesses (OSAGWI) is issuing a series of information papers that describe what we know today about military equipment or procedures used in the Gulf War. These information papers include reports on the Fox reconnaissance vehicle and Mission Oriented Protective Posture (MOPP) gear . The purpose of the report on the M8A1 Automatic Chemical Agent Alarm (ACAA) is to provide a basic understanding of chemical detection equipment relevant to several ongoing investigations of incidents of possible chemical weapon detection. The report focuses on the components of the M8A1 alarm system, how it operates, and what could cause it to sound an alarm.

The paper explains that the alarm's design allows it to detect some-but not all-chemical weapon agents, but that the design of the M8A1 also allows it to alarm on many substances that are not chemical warfare agents.

In addition, the report says many false alarms were a result of a low battery. It says troops operating the alarm in the Gulf reported the battery lasted only 30 to 32 hours in the desert environment compared to its normal time of about 72 hours.

The Information Paper says the alarm is placed upwind from a unit and can detect very small quantities of VX and the entire G series of nerve agents which include sarin, soman and tabun. However, it cannot detect other chemical agents, such as mustard gas or Lewisite, or the series known as blood agents.

Furthermore, since the detector works by measuring the current given off by heavy ions found in VX and the G agents and not those agents themselves, it alarms on other substances with similar patterns of heavy ions. The paper lists the following known substances that can cause the alarm to sound: After-shave lotion; Rocket propellant smoke in heavy concentrations; Paint fumes; Diesel and gasoline exhaust fumes; Floor wax; Insecticides such as Diazinon and Malathion; Perfumes; Green smoke grenade emissions; Cologne; Vapor from gasoline and JP8 (a clear fuel); Burning oil, JP4 fuel and kerosene; and Cigarette smoke.

Because so many "interferents" can set off the alarm, the M8A1 is used as a cautionary warning signal-that is, it tells troops to don protective suits and remain in them for the 20 or more minutes it takes to perform the much more accurate detection test with the M256A1 chemical kit, which can screen out these interferents.

The Defense Department plans to replace the M8A1 alarm system with the M22 Automatic Chemical Agent Detector Alarm (ACADA) starting in March 1998. The new detector has the advantage that it can sense mustard agent vapor, in addition to nerve agent vapor. Also, the ACADA is expected to have fewer false alarm responses to many known interferents such as gasoline and diesel exhausts.