TASER Electronic Control Devices Review Of Safety Literature

Sharp pain, temperature, crude touch (τ about 650 µs)
III A-δ myelinated fibers
About 3 microns (1-5 microns) diameter
About 40 V/m threshold (24-120 V/m)
Perceptions of pain, discomfort, and sensation overload are carried not only by
the myelinated axons as described above (type III A- δ fibers) but also by small,
nonmyelinated type IV C axons. These are the cells thought to be responsible for
dull, aching diffuse pain (as opposed to the sharper pain carried by type III fibers).
From the work of Li and Bak 10 it can be estimated that C fibers have stimulation
thresholds about 20 times higher than those of sensory A fibers. Specifically:
Dull, diffuse pain; post-ganglionic autonomic fibers (τ about 500-600 µs;
estimated from Li and Bak) 10
IV C unmyelinated fibers
About 0.5-2 microns diameter
Thresholds of about 500 V/m or higher.
Cardiac vs. Muscle Stimulation
By comparison to motor or sensory myelinated nerves, the heart’s excitability (as
in pacing of the heart) is relatively low for brief stimuli. This is because, despite
the fact that the minimum (rheobase) level of stimulus needed for long duration
pulses is probably similar between cardiac cells and myelinated nerves 8 cardiac
strength-duration time constants are about 2-3 ms or higher (i.e. at least 10-20
times higher than the A- α motor neuron fibers which control skeletal muscle contraction).
The heart is also located deep within the torso (as opposed to the
skeletal muscle which comprises much of the superficial layers of the torso and
into which electrical weapon probes may penetrate if they embed just below the
skin). Thus, relatively little, if any, current will pass through the heart. This effect
of relatively low penetration into the heart given surface or near-surface stimulation
of tissues is well known and well studied both in the electrical safety literature
as well as the medical literature of transthoracic pacing and defibrillation.
After Effects
Muscles immediately relax after the nerve signals are released. This is most
clearly demonstrated by the numerous videos of ECD-exposure volunteers getting
up immediately after an exposure.
1.8 The Strength of the Contraction
it is commonly believed that the induced muscle contraction is severe. In fact, it is
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