TASER® MEDICAL STUDIES
Summary

INTRODUCTION AND SYNOPSIS

When the TASER® was introduced over 20 years ago, there was considerable apprehension and disbelief in the United States, how a device utilizing a 50,000 Volt output to immobilize an attacker could be non-lethal, yet cause no latent medical conditions to the human body. In 1997, following more than 20 years of review and analysis by many physicians in journals such as The Annals of Emergency Medicine and The Journal of Forensic Sciences, non-lethality is now a fact.

HOW IT WORKS

The AIR TASER® is a close range standoff self-defense device that does not depend on damage or destruction of tissue or organs to be effective. This small hand held system uses compressed air to disperse two small probes up to 15 feet.

These probes are connected by wires to the hand held launcher and send a powerful electric signal into the nervous system of an assailant. Upon contact, the two probes complete an electrical circuit and current is transmitted from the batteries to the target. This causes the individual to fall to the ground helpless and incapacitated as the brain loses control over the rest of the body.

The AIR TASER® is effective because it overrides the nervous system of the human body. The human nervous system communicates by transmitting simple electrical impulses. A nerve sends a message much like an electric telegraph with a series of electrical blips. As illustrated schematically below, the AIR TASER® sends a series of discrete electrical impulses (called TASER®-Waves ), quite similar to those used by the human body for communication.

The TASER®-Wave’s output overpowers the normal electrical signals within the nerve fibers. The nerve communication blips wash out all normal signals in a sea of "white noise" created by TASER®-Wave electrical impulses. When subjected to TASER® impulses, the human target loses control of the neuromuscular system and cannot perform coordinated action.

The method of incapacitation by the TASER® is the least violent means possible for ending dangerous situations. In fact, a study was conducted on patients admitted to the Emergency Department of the King/Drew Medical Center in Los Angeles, who had been shot with a TASER® between July 1980 and December 1985. These 218 subjects were compared to 22 similar patients shot with .38 Specials. In this report, 92% of those patients stated they had total amnesia about the event and could not remember being subjected to the TASER® Furthermore, the study indicated the TASER® did not cause conscious pain.

In contrast, alternative non-lethal products, such as pepper and chemical sprays are known to cause tremendous pain when used. Pain is the primary means of causing the target to stop. Chemical sprays rely on a severe burning sensation to disable an attacker. Pepper sprays, made from oleoresin capsicum, the hot ingredient in cayenne pepper, cause severe inflammation to an assailant’s eyes and respiratory system. (Using these types of sprays is similar to spraying acid into someone’s eyes.) Further, these sprays cause inflammation of the mucous membranes and can trigger severe asthmatic reactions. These aftereffects can last up to several hours.

 

AIR TASER® EFFECTIVENESS

The first concern of users evaluating any self-defense product is that it must be effective. Using actual field data comparing performance of the TASER® to a variety of handguns, the actual effectiveness of the TASER® surpassed all but the .357 Magnum, to which it is equal with an 86% instant incapacitation rate. Test results calculated the percentage of individuals immediately incapacitated. Instant incapacitation is defined as immediately rendering the target to the ground, temporarily unable to continue to fight or resist.

This particular test is actually biased against the TASER® because the vast majority (86% in one study) of the people shot by the TASER® were on the drug PCP. (The TASER® is the Los Angeles Police Department’s weapon of choice for those on PCP, crack, heroin, and mentally deranged lawbreakers.) This extremely dangerous and powerful drug is known to provide users ‘superhuman’ strength. Moreover, PCP can cause individuals to be oblivious to pain. Frequently people on PCP break their own bones without distress and are infamous for their capability to absorb bullets without being instantly incapacitated.

The TASER® is highly effective at immediately incapacitating offenders because its electrical signal penetrates the nervous system regardless of the placement of its probes. The entire human body is covered by a neural net that the AIR TASER® uses to knock out its target. The probes do not have to penetrate the flesh or cause bodily harm to be effective because the TASER®-Waves can penetrate approximately two cumulative inches of clothing. For a bullet to be instantly effective, it must hit a vital organ such as the heart or brain and cause severe trauma and shock to the body. Similarly, chemical and pepper sprays must hit an assailant in the face; no easy task even for trained law enforcers in fast moving confrontations. Moreover, the sprays’ weaknesses are their limited effective range, their imperfect disabling of attackers, and their sensitivity to environmental conditions like winds which can blow chemicals back onto the user. These chemicals are also not discrete and may adversely effect the user and others. On the other hand, the AIR TASER® provides more effective range, is not affected by wind and is discrete in usage.

The AIR TASER® has proven to be instantly effective and requires less training than other self-defense technologies. The graphic on the following page illustrates the effective target areas of the AIR TASER® far surpasses those of chemical sprays and even handguns.

 

THE TASER® SAFETY RECORD

Because the TASER®-Wave "jams" the communication system of the body, it does not need to cause bodily injury to be effective. The AIR TASER®’s output power is about equal to a Christmas tree light. Although its output is 50,000 Volts, its maximum average power output is six Watts. The AIR TASER® generates 10-15 pulses per second. Each pulse is approximately .4 Joules. At 15 pulses per second and .4 Joules per pulse, 6 Joules per second is the maximum delivered energy per second. It is the nature of the signaling effect within the nervous system that makes it effective. The following graph uses equations developed by the Underwriters’ Laboratories, Inc. for electric fence safety guidelines. The shaded area is considered safe electrical exposure for a two-year-old child or a 75-year-old person. Note the AIR TASER®’s output is approximately 1/1,000th of a potentially dangerous level.

Numerous studies have confirmed there are no long-term effects from TASER®-Waves. As noted in the graph on the following page, a University of Southern California Medical Center study concluded that in addition to its non-lethality, the TASER® leaves 0% long term injuries. These findings compare quite favorably to the data in the Annals of Emergency Medicine study concerning the .38 Special handgun wounds. Only 50% of those shot with a .38 Special survived and of those survivors, 100% had sustained permanent injuries.

In all of the studies of TASER® related fatalities, not one case reports a fatality directly caused by use of the TASER®. The Underwriters’ Laboratories, Inc. Bulletin of Research Number 14 of December 1939 (a study of electric fences and electrocution) enumerates the following possible causes of death from electric shock:

1. Loss of function of respiratory muscles, producing death from asphyxia. This method of death requires paralysis of the lungs for a period of at least several minutes. The lack of oxygen could cause brain damage and death. The AIR TASER® runs off a nine-volt battery that would drain in less than two minutes if it could run nonstop without breaks in the TASER®-Wave cycle. Even if the device was able to run nonstop and the current ran continuously across the diaphragm muscles in the mid thorax, the duration of the paralysis would be too short to induce death by asphyxia. More importantly, the design of the AIR TASER® ensures that a long and continuous flow discharge will not occur. Death due to paralysis of respiratory muscles has never been reported with the use of a TASER®. (See Section 1. Automatic Impulse Regulation for details.)

2. Hemorrhage resulting from increased blood pressure. Dr. Robert Stratbucker, MD, Ph.D., MS, PE is the most respected doctor in non-lethal electronic weapons testing and safety evaluations. Dr. Stratbucker has written over 23 publications and presented his work in numerous technical conferences and scientific exhibits. Some of his works include the following relevant topics: potential cardiac hazards in the use of hand-held electronic law enforcement devices, relative immunity of the skin and cardiovascular systems to the direct effects of high voltage, cardiac arrhythmia and defibrillation, current density distributions during transcutaneous current pacing, and electrical characteristics of the skin. Dr. Stratbucker’s study in Section V of this report, demonstrated that even direct application of the TASER® output to the heart "showed only a mild and transient effect on blood pressure." No death by this means has ever occurred in an individual shot with a TASER®.

3. Heart Failure. Dr. Stratbucker performed tests by applying the TASER®-Wave pulsed wave form directly to the cardiac tissue via an intracardiac electrode and found "no effect on cardiac rhythm or pumping." He also tested the pulsed waveform for interference with cardiac pacemakers. Dr. Stratbucker found "only when the shocks were delivered directly to the pacer itself did erratic pacing occur. Following the termination of the shocks, the rhythm returned promptly to pre-shock regularity." The designs of modern pacemakers withstand the pulses of electrical defibrillators that are several hundred times stronger than TASER® pulses. Tests at the Cordis Medical Lab in Florida have confirmed this.

There have been several reported heart failures in individuals shot by the TASER®. However, in all cases but one there were sufficient amounts of PCP or other drugs in the blood to have caused the death. The one case the TASER® was listed as a contributing factor involved a person with a serious heart condition who was on PCP. However, the doctor performing the autopsy listed the TASER® as possible contributing factor. In none of these cases did the heart failure occur until at least 15 minutes after being shot with a TASER®. Electrically stimulated heart failure would be immediate and would occur during the shock. The patient would die within two to three minutes. There is no plausible mechanism for the TASER® to cause a delayed heart failure. Instead, it appears to have been listed as a potential cause in the above case in the name of conservatism. (By law, coroners must list any possible cause.)

4. Respiratory failure due to nervous inhibitions or damage to the nervous system. The TASER® does not produce enough power to damage nerve tissue. It simply produces electrical signals confusing the nervous system by overloading the nerve fibers with meaningless signals. No deaths of this nature have been reported.

5. Skin and flesh burns. A tremendous amount of heat generated by high power currents would have to occur for this type of burn. The nine-volt battery of a TASER® does not produce enough power to cause any more than perhaps slight surface burns. Testing in hospital settings has shown that the TASER® does not to cause burns.

The reports included in this document provide in-depth analysis of the safety of the TASER®’s electrical waveform. They absolve the TASER® from any significant involvement in the drug-related deaths of individuals shot by TASER®s.

 

THE AIR TASER® -- UPDATED FOR INCREASED SAFETY

The AIR TASER® is truly a next generation product compared to the original TASER®. In addition to being a non-firearm, the new design actually increases the safety of the AIR TASER® relative to the original TASER®. The AIR TASER® upgrades the capabilities of the TASER® with the following improvements:

1. Automatic Impulse Regulation. While "AIR" refers to the fact the AIR TASER® is a non-firearm; it also stands for Automatic Impulse Regulation. In the original TASER®, the user is responsible for holding down the trigger switch to continue applying electrical charge to the target. The first problem with this approach is the unit will not disable the attacker if the current is not applied for a sufficient amount of time. The natural reaction is to release the trigger after firing -- even trained police officers have failed to hold down the trigger switch after firing. This allows for human error to render the device useless. A second problem with allowing the user to control the application of charge relates to liability. Occasionally, police departments have been charged with the pretense that an officer applied the charge too long and tormented the target (even though there is no pain sensation per se with the TASER®).

The AIR TASER® uses an automatic timing mechanism to apply the electric charge. Upon firing, it follows a pre-set algorithm to apply the electric current. (The following timing cycle algorithm of the AIR TASER® is: Approximately 7.5 seconds on, 1 second off, 6.5 seconds on, 1 second off, 6.5 seconds on, 1 second off, 6.5 seconds, 1 second off, 3 seconds on.) This removes user error from the loop, making the product safer to use. It also allows the user to place the device on the ground and run. The unit will continue to disable the target automatically for the next 30 seconds and keep an attacker disoriented and on the ground for several minutes.

2. Stun Gun Backup. After firing the probes, the AIR TASER® immediately functions as a contact stun gun. This timing cycle provides protection against a second attacker and is a powerful backup in the unlikely event the target is missed.

 

ELECTRIC STUN GUNS

Stun guns or electronic standoff devices use the same basic electric impulse generator (patented by the TASER® inventor, John Cover) used in the TASER®. Stun guns generally discharge a nine-Volt battery through a transformer system. This creates an electric spark between two external electrodes at voltages up to 50,000 Volts. When these electrodes contact an assailant, the electrons choose the path of least resistance traveling through the aqueous human flesh rather through air or clothing. The presence of the electric current in the tissues disrupts the human nervous system. However, because the distance between the electrodes is always two inches or less, the incapacitation is not as sure as with the AIR TASER® since the signals are so localized. The initial electrical current can knock an attacker down or at a minimum keep the aggressor at bay. Depending on the length of the initial contact, the assailant can recover within minutes or less. When the charge is applied for longer time periods, measured in seconds, the disequilibrium within the nervous system increases.

Stun gun systems require the user to directly contact the assailant and apply the charge. Incapacitation requires an aggressive user. It obligates the continued attention of the user for protracted applications during conflict. Direct contact is eliminated with the AIR TASER®’s ability to disperse probes up to 15 feet and spreading the electrical probes much further apart. However, the AIR TASER®’s stun gun backup does provide an adequate defensive backup system.

The stun gun market is unfortunately permeated with claims of extremely high voltages. The advertised voltage of most stun guns is greatly exaggerated. In reality voltage is an indication of how far a spark can jump and therefore how much clothing the stun device can penetrate when the spark must penetrate fabric. The rule of thumb is 28,000 Volts per inch. This is the only true benefit of using high voltages. The effectiveness of electronic output is a function of amps, power, frequency, and LASTLY voltage.

 

ABSTRACTS OF MEDICAL ATTACHMENTS

I. NATIONAL COMMISSION ON THE CAUSES AND PREVENTION OF VIOLENCE

This document is the result from a special Presidential Commission chartered to investigate policy toward violence and violent crime.  The recommendation strongly supports non lethal weapons such as the AIR TASER®.

II. THE TASER® DEVELOPMENT PROGRAM

Jack Cover, inventor of the TASER® and former Chief Scientist for the Apollo Moon Landing Program, describes the scientific process of developing the TASER®-Wave output. The development program included extensive literature review of scientific data and years of testing on animals, him and other volunteers and consultation with many prominent physicians. Note in the included charts the electrical output of the TASER® is three orders of magnitude below (1/1,000 below) a potentially dangerous level. Underwriters’ Laboratories, Inc. Bulletin of Research Number 14, U.S. Consumer Product Safety Commission, National Bureau of Standards, and expert consultants have determined this level.

III. ELECTRONIC GUN INJURIES: Annals of Emergency Medicine

In this comparative study of .38 Special handgun wounds and TASER® injuries, the authors found none of the individuals shot by a TASER® had any long-term injuries. All of the gun shot survivors had major injuries (half of the gun shot victims died). Only 1.4% of the individuals shot by TASER®s died – all had "sustained toxic (acute) levels of PCP…" None of these individuals expired during the actual TASER®ing.

IV. EFFECTS OF THE TASER® IN FATALITIES INVOLVING POLICE CONFRONTATION: Journal of Forensic Sciences:   This article reviews 16 deaths of people shot by a TASER®. All were on "hard drugs – cocaine, PCP or amphetamine." All of the individuals died of causes such as "multiple gun shot wounds" (this is extremely difficult to implicate the TASER® in these cases); "blunt force trauma" (associated with a "choke hold"); or "acute PCP intoxication" (overdose). The TASER® was implicated as a possible contributing factor in one case where the individual had a chronic heart condition and had sufficient levels of PCP to explain death. The TASER® did not appear to have been a significant factor in any of these cases. Moreover, none of the individuals expired until up to three days after the TASER® incident.

V. UNIVERSITY OF NEBRASKA MEDICAL CENTER

(The stun gun used in this test uses the same electronic circuitry and output as the TASER®.) Dr. Stratbucker’s test concluded, "Cardiac tissue, normally far removed geographically from the stun gun in its customary mode of application, would not and could not be stimulated even if it were in direct contact with the gun due to the unique characteristic of heart tissue requiring relatively prolonged stimulating pulses for effective stimulation."

This testing demonstrated the TASER®-Wave form output would not cause heart attacks even in individuals fitted with cardiac pacemakers. "The device appears to be incapable of causing thermal effects such as burns to the skin or other tissues."

VI. DR. STRATBUCKER & ASSOCIATES

Dr. Stratbucker reconfirms his earlier findings on electrical emissions from stun pulse generators, delivered to the body surface in the recommended manner do not cause serious cardiac rhythm abnormalities in the otherwise healthy adult heart. "This study investigated electrical outputs equivalent to 400% the capacitance and 300% the battery voltage of the standard AIR TASER®, an adequate margin of safety appears to exist."

VII. U.S. Consumer Product Safety Commission (USCPSC) Studies of the TASER®

This is a transcript of several independent tests of the TASER® commissioned by the USCPSC on the TASER®.  The results were unanimous that the TASER® is non lethal.

VIII. VARIOUS TASER® BACKGROUND DATA

The section includes a report on a human subject who dropped to the floor in less than one second during a hospital TASER® test. It also includes notes from the use of a modified TASER® on lions. All of the tests successfully felled the target animal. In addition, this section includes two newspaper articles and a page from the Journal of California Enforcement. This section ends with a medical bibliography and summary.



* The AIR TASER® has now been replaced by the C2 TASER®.


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