TASER Electronic Control Devices Review Of Safety Literature

ual, no vulnerable period escapes the TASER ECD pulsing – the TASER ECD
pulse hits every T-wave.
Urban Myth of Delayed VF
As discussed earlier, a death from electrically induced VF is instantaneous. The
induction takes a few seconds and collapse follows within another 5-15 seconds.
In the typical arrest-related death (with or without ECD usage) the collapse occurs
minutes to hours after control is gained. This has forced some ECD critics to
speculate that there must be some mysterious mechanism for a delayed apperance
of VF.
The sole “evidence” for this speculation is an anecdote of a Danish electrician
who had a supposed cardiac arrest during a soccer match. 31 He blamed it on a
work related shock 12 hours previous. One would have to note that he had a financial
incentive to blame his cardiac condition on a job injury rather than on his
recreation. Whatever happened he did not die.
Even with high current industrial or lightning electrical injuries delayed VF is not
seen. 32
Safety Margin for a Single Pulse in the Vulnerable Period
The TASER M26 main phase delivered charge is about 85 µC (microcoulombs)
and the TASER X26 delivers about 100 µC. The critical parameter of electrical
stimulation by short duration pulses is the electrical charge. 3 This has been more
recently confirmed for cardiac stimulation with short duration pulses, such as
those from the TASER ECDs. 33
Green Model: 130:1 (X26) and 153:1 (M26) Safety Margins
Green investigated the VF induction threshold for canines stimulated along the
length of their body. 34 He found that the lowest threshold occurred with a 5 ms
quarter sine wave and was 2 A. Integrating, we find a minimum required charge
of 6.5 mC (millicoulombs). On the basis of many studies, it is common practice to
use a normalization factor of 2 to 1 to go from canine results to human as humans
are so much larger than the small dogs typically used in these laboratory
experiments. 8 This suggests a human VF threshold of 13 mC. With the TASER
X26 charge of 100 µC we can calculate the safety margin as:
Safety margin = 13 mC ÷ 100 µC
= 130:1
For the TASER M26 the safety margin would then be even higher at:
Safety margin = 13 mC ÷ 85 µC
28