Human Electro-Muscular Incapacitation FAQs

Q1. What is a Human Electro-Muscular Incapacitation device?
A1. A Human Electro-Muscular Incapacitation device, such as the TASER® X26™, TASER® M26™ or Stinger S-200, is a non-lethal weapon designed to temporarily incapacitate individuals. It provides the operational commander a counter-personnel non-lethal weapon that can support missions involving single target or crowd engagement situations where the use of lethal force is not a viable option.

Q2. How does it work?
A2. A Human Electro-Muscular Incapacitation device emits an electrical waveform that overpowers the normal electrical signals within the subject’s nervous system and causes involuntary muscle contraction and temporary loss of motor control. Exposure to this waveform results in temporary electro-muscular incapacitation. Electro-muscular incapacitation is the general term to describe the immobilizing effect that occurs from exposure to an electric stun device.

One example of a Human Electro-Muscular incapacitation device is the TASER® X26™. This device operates by firing two barbed probes from an attached cartridge. The two probes are propelled into the subject by a compressed nitrogen cylinder. The two probes are connected to the weapon with high voltage insulated wires. When the weapon's trigger is engaged, electrical signals are transmitted through the wires. Upon contact with the body, the electric signals produce tetany, a state of continuous muscle contraction, rendering the subject temporally incapacitated. The barbs are projected at slightly different angles, so by the time they impact the subject's clothing or skin, they are distanced from each other by several inches. This distance completes the electric circuit over a wide area of muscle mass, making it extremely effective at producing an electro-muscular incapacitation effect.

The stimulus lasts for a pre-programmed length of time after the trigger is pulled or until the device’s safety switch is manually engaged. To reinitiate the cycle, the trigger can be pulled again after the stimulus has stopped. Presently, cartridges are available that fire the probes at ranges of 21, 25 or 35 feet. Unlike blunt trauma munitions, this payload provides a universal effect on personnel. 

Q3. What human effects testing has been done?
A3. Human Electro-Muscular Incapacitation devices have undergone extensive human effects testing and analysis. The Air Force Research Laboratory, Human Effects Center of Excellence, Naval Health Research Laboratory and contracted researchers from academia such as The Pennsylvania State University have done extensive work to understand and characterize electro-muscular incapacitation effects at various exposure durations. The testing, which has been reviewed by the Department of Defense’s Human Effects Review Board, ensures the implementation of proper operator training and safety margins between what is operationally effective and potentially injurious. Specifically, in June 2008, the Human Effects Review Board accepted the human effects testing conclusion that the TASER® X26™ does not pose any serious health risks and agreed that sufficient bioeffects research had been completed for the TASER® X26™ acquisition process to move forward.

This Human Electro-Muscular Incapacitation human effects research is the key source of data used to support legal, policy and treaty reviews for this type of non-lethal weapon. Any new weapon, lethal or non-lethal, developed under the auspices of the Department of Defense is required to undergo a thorough legal, policy and treaty review prior to fielding. All fielded non-lethal weapons have undergone legal reviews to ensure compliance with obligations assumed by the United States under applicable treaties, customary international law and the law of armed conflict.
Q4. How has the use of Human Electro-Muscular Incapacitation devices in the military evolved?
A4. In 2003, the U.S. Army materiel development community received a statement of urgent need from the theater requesting an “electro-muscular disruptor.” In response, the Army sent the TASER® form of an Urgent Materiel Release. From 2004 to 2006, the Army fielded the TASER® X26™ through the same Urgent Materiel Release process. The Army currently has more than 1,200 TASER® X26s™ in theater as part of an Urgent Materiel Release. The Army’s Non-Lethal Capability Sets, which the Army plans to field to numerous locations from FY08 to FY12, now include the TASER® X26™.

In 2004, the Joint Non-Lethal Weapons Program funded and assigned the U.S. Army as the lead for development and fielding of a Launched Electrode Stun Device, a hand-held stun device capable of non-lethally incapacitating personnel at a range of up to 32 feet. This initiated the formal military acquisition process to field Human Electro-Muscular Incapacitation devices. The test plan was completed in 2005, with safety and environmental testing completed during FY06 and FY07. An independent evaluation and a final report will be completed in FY08. The Army is now approaching an Acquisition Milestone C (procurement) decision, with official release of the TASER® X26™ to follow. 

Parallel to the Army’s efforts, the U.S. Air Force worked to field Human Electro-Muscular Incapacitation devices. The Air Force approved the use of the TASER® M26™ in 2004 and the TASER® X26™ in 2007. Individual USAF units may purchase the devices, and the Air Force has also released Human Electro-Muscular Incapacitation devices in its Non-Lethal Capability Sets. The Air Force currently has about 1,000 devices in its inventory, with two documented, successful engagements in the U.S.

The U.S. Coast Guard issued a report in FY08 that recommended removing from service TASER® X26s™ that have been submerged or sprayed with salt water. The Coast Guard will not consider purchasing Human Electro-Muscular Incapacitation devices until a capability that can meet the maritime operational requirements is developed and available.

Current Human Electro-Muscular Incapacitation commercial-off-the-shelf technologies address the capability gap of disabling individuals at short ranges. However, there is still a joint capability gap of disabling individuals or groups of people at longer ranges for longer durations. Human Electro-Muscular Incapacitation technology currently provides the only technically viable solution to fill this gap. As a result, there is an ongoing military effort to move to the next generation of Human Electro-Muscular Incapacitation technologies that have longer range, are more energy efficient and safely produce incapacitation for longer durations.

Q5. Why do warfighters need Human Electro-Muscular Incapacitation Devices?
A5. Non-lethal weapons continue to evolve in response to the needs of our warfighters as another “tool in the tool box.” Non-lethal Human Electro-Muscular Incapacitation devices are explicitly designed and employed to temporarily incapacitate personnel while minimizing human fatalities, permanent injury to personnel and undesired damage to property and the environment.
Non-lethal weapons do not replace the need for lethal force but enhance the capability of U.S. forces to accomplish mission objectives. Non-lethal weapons are not necessarily totally harmless or totally non-lethal, but they are used to achieve military objectives with the intent of greatly reducing fatalities and permanent injuries in comparison with the use of lethal weapons for the same purpose. However, there is no guarantee that non-lethal weapons will have the desired effect on every target every time.

Q6. How are warfighters trained to use Human Electro-Muscular Incapacitation devices?
A6. The Inter-Service Non-Lethal Individual Weapons Instructor Course at Ft. Leonard Wood, MO, is a joint non-lethal weapons course that trains Service members to become instructors in the use of non-lethal weapons. They then return to their units to train their Service members in the use of these weapons.

A course on the use of Human Electro-Muscular Incapacitation devices is part of the Inter-Service Non-Lethal Individual Weapons Instructor Course training. In this course, Service members learn rules of engagement and techniques and procedures for using this non-lethal weapon. They also participate in firing demonstrations.

Q7. What organizations are involved?
A7. The following organizations have participated and plan to continue developmental and logistical support of the program:

  • Department of Defense
    • U.S. Army (Lead Service)
    • U.S. Marine Corps
    • U.S. Air Force
    • U.S. Navy
    • U.S. SOCOM
  • Department of Homeland Security
    • U.S. Coast Guard
  • Department of Justice
  • Human Effects Center of Excellence
  • Joint Non-Lethal Weapons Directorate