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The enclosed information has been extracted from the report “Update on Electrical
Devices as Less Lethal Options. Report for ACPO and NIO, June 2001” by the Home
Office Police Scientific Development Branch. All information has been included that
relates to Taser International and their products without mentioning any other
manufacturers products.
These results have been provided for your information only and should not be
used for advertising purposes or to exploit any favourable comments as an
endorsement of this product.

1. TASER INTERNATIONAL
Taser International, formerly known as Air Taser, was formed in 1993. Although
initially geared towards the civilian market, the company are now heavily promoting
their products within the North American law enforcement community.
Taser International produces two series of tasers: the 34000-Series and the M-Series.
•
Air Taser 34000-Series (see Figure 1): These models are not shaped like
firearms. They are 7W systems (pulse energy = 0.44J) and weigh 8-9 ounces (227255g). These models are single shot and have a detachable single laser sight. They
have an automatic 30-second timing cycle that is activated once the darts have been
deployed, although this can be turned off at any time by the person controlling the
unit.
•
Advanced Taser M-Series (see Figure 2): This series comprises the M18
model and the M26 model. Both models are shaped like conventional handguns, have
single laser sights built in and weigh 18 ounces (510g). The M18 model has a power
output of 18W and a pulse energy of 1.76J. The M26 model has a power output of
26W although pulse energy is also reported to be 1.76J. Both models are single shot
and have an automatic 5-second timing cycle that is activated once the darts have
been deployed, although this can be turned off at any time by the person controlling
the unit. This model can be used as a ‘touch stun’ device when the cartridge is
removed. More than 750 North American and Canadian police forces are now
believed to be using the M26.
All Taser International cartridges use compressed nitrogen as the propellant.

FIGURE 1: The Air Taser 34000-Series

FIGURE 2: The Advanced Taser M-Series

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2. TASER OPERATIONAL ISSUES
A number of important generic points have been learned about tasers that can affect
their use operationally.
2.1
Batteries
Different models of taser require different types of batteries, usually either alkaline or
rechargeable are recommended. Different types of batteries have varying levels of
performance in terms of their power, both in use and when stored, and when used in
different climates. This point is best illustrated by taking the Taser International M26
Advanced Taser as an example.
Taser International recommends the use of either Energizer NiMH rechargeable
batteries or Duracell Ultra alkaline batteries. The M26 takes 8 AA batteries. Each
NiMH rechargeable has a voltage of 1.2V, resulting in an overall voltage of 9.6V.
Each Duracell Ultra battery has a voltage of 1.5V, resulting in an overall voltage of
12V. Despite the NiMH rechargeable batteries having a lower voltage than the
Duracell Ultras, they can deliver higher currents, resulting in an increased output
power.
The performance of the different types of batteries with continuous usage varies. This
is shown in Figure 3, which plots the change in voltage for each of the types of
batteries against the number of uses. The performance of the Duracell Ultra batteries
declines steadily throughout the lifetime of the batteries, with the voltage dropping
with every usage. With the NiMH rechargeable batteries, the voltage and therefore
performance remains constant for a long period with a rapid decline after a large
number of uses.

9

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/RZ %DWWHU\ ,QGLFDWRU /HYHO

9

Voltage

9

1L0+ 5HFKDUJHDEOH

Number of Uses

FIGURE 3:

Change in Voltage of NiMH and Alkaline Batteries with Number of Uses

These effects can be observed by firing, side-by-side, two tasers – one powered by
Duracell Ultra alkaline batteries and one by NiMH rechargeable batteries. The initial

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spark rate will be higher when using the rechargeable batteries, due to their higher
power. Also, with continuous 5-second cycles, the fast spark rate of the NiMH’s will
be maintained whereas with the alkaline batteries the spark rate will decrease rapidly
with continuous cycles. Note: when the taser is not fired in continuous cycles, this
decline in performance will not be as rapid as the batteries will have had time to
recover in between uses.
The M26 has a low battery indicator at its rear that indicates when the overall battery
voltage has dropped below 11.1V which was designed for use with Duracell Ultra
batteries to allow the user to know when their performance had dropped below a
certain level. When the taser is used with NiMH batteries, however, this indicator
shows a low battery indication even when the batteries are fully charged. This is also
shown in Figure 3.
The performance of the different types of batteries also varies in cold conditions. The
Royal Canadian Mounted Police (RCMP) carried out tests on both types of batteries at
temperatures varying from –20OC to +40OC. They found that the spark rate using the
Duracell Ultra batteries was significantly slower at –10OC and –20OC. The spark rate
for the NiMH Energizer batteries was much more consistent, although there was some
reduction at –20OC. For more information on performance of tasers at extreme
temperatures, see section 3.7.
When the spark rate is lower than normal, due to either partly exhausted or cold
batteries, the number of pulses per second reaching the target will be lower. This will
result in muscular contraction/relaxation cycles at the target instead of the overall
complete muscle stiffening required for total muscular control. This effectively means
that tasers operating at lower spark rates are not as likely to lead to incapacitation.
From the evidence provided so far, it would appear that rechargeable batteries are the
best option. It should be noted, however, that rechargeable batteries self-drain at
approximately 1% per day. Therefore, if the taser is not used for a period of time and
the batteries are not recharged, there will be a large reduction in the power. If
rechargeable batteries are used, it is extremely important to remember to recharge
them at regular intervals – Taser International recommend doing this every two
weeks.
Taser International is currently working on a rechargeable taser. This would allow the
M26 to be plugged into a recharger via the dataport every two weeks or so. Extra
connections have already been incorporated into the existing dataport so that existing
tasers can use the recharging capabilities when they are introduced (expected to be
before the end of 2001).
2.2
Effectiveness
Effectiveness ratings for the 5-7W systems have been quoted as between 85% down
to as low as 50%. It was found that, with the lower-powered systems, focused
individuals were able to fight through the effects of the electricity and could continue
with an attack. 26W tasers were introduced as an alternative to 5-7W systems as they
were believed to be more effective. The lower-powered systems are believed to
interfere with the communication signals within the nervous system of the target,
while the new higher-powered tasers are believed to completely override the central

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nervous system and directly control the skeletal muscles, causing an uncontrollable
contraction of the muscle tissue. This is said to be close to 100% effective regardless
of the pain tolerance or mental focus of the individual.
Since the introduction of the higher powered tasers, a large number of volunteers have
been subjected to their effects, mainly American and Canadian police officers,
including those who had previously been able to fight through the effects of the
lower-powered versions. The feedback from these volunteers indicates that the higherpowered tasers are indeed more effective with few people capable of fighting through
the effects. Operationally, however, there have been a number of cases where
individuals have not been fully incapacitated by the device. Their muscles have
contracted while the taser is active, but they have not fallen to the ground and, as soon
as the power is turned off, they have been able to remove the barbs from themselves
and continue with their attack.
Since the introduction of the higher-powered tasers, there have been a number of
operational uses allowing some initial effectiveness data to be obtained. The figures
shown in Table 1 relate to the use of the M26 Advanced Taser.
Source of Data
Taser International
American Police Force
American Police Force
Canadian Police Force
TABLE 1:

# Cartridges
Fired
257
16
33
50

# Times
Ineffective
19
3
3
13

%
Ineffectiveness
7.3%
18.8
9.1%
26.0%

Ineffectiveness Data For M26 Advanced Taser

There are a number of possible reasons for the failure of taser devices. These are
summarised below:
•
Clothing – although the electricity can arc across a gap up to a certain
distance (see section 5.5 for more information about this), there may be some
situations where the thickness of the clothing worn exceeds this distance. This is
particularly so in very cold climates where heavy jackets are worn. Also, if clothes are
loose and hanging and the barb(s) penetrate the clothing only and not the body, then
the current flow could be broken when the clothes flow away from the body;
•
Low batteries – the issue of batteries has been discussed already and reasons
have been given as to why they are likely to fail. This has been recognised as a serious
issue by the users and trainers in America and Canada and a number of failures, which
had initially been thought to be due to clothing, are now suspected to have been
caused by low batteries. They have found that often, when an officer first receives
their taser, they will demonstrate its sparking to colleagues - usually a number of
times. They may also do a ‘spark-test’ before taking their taser on duty with them to
ensure it is working correctly. These actions combined can seriously affect the
performance of the taser when the time comes to use it operationally;
•
One or both darts miss the target – this could be due to a number of reasons
including: operator error, errors in the sighting system, errors in the cartridge, a
moving target and the target being out of range. Generally speaking, unless both barbs
hit the target, the circuit will not be completed and the electricity will not flow
through the target;

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•
Subject fought through the effects of the electricity – this has been
discussed already and it is recognised that this may still be a possibility even with the
new higher-powered tasers. Reasons for this happening could include the barbs not
being sufficiently separated or affecting a group of muscles that are not sufficiently
sensitive;
•
Cartridge failure – identified already as the cause of failure in some cases;
•
Problem with taser – other than due to cartridge failure or low batteries;
The path that the electric current will take after the barbs have been fired at a target is
often difficult to predict. Essentially, electricity will flow along the path of least
resistance, or will follow a number of different paths. Although ideally the full charge
would travel along the wire to the first barb, through the subjects’ body, then out
through the second barb, this is not always the case. Contributing factors to the
unpredictability include: the presence of metal or other good conductors; the presence
of water; highly resistant material at the target; and arcing across the wires.
All of the figures for effectiveness quoted previously have only included those cases
where a cartridge was actually fired from the taser, however the taser is often also
used to gain compliance in other ways and often the use of the laser sight(s) alone will
be enough to gain compliance. In other instances, firing the taser without a cartridge
inserted is enough to gain compliance; this allows the subject to see the effects of the
electricity sparking and hear the loud crackling caused by the electrical discharge
across the electrodes. Additionally, some tasers can be used in stun gun mode to
provide a touch stun capability, this method of application is often used in some
American and Canadian forces. Figures from Taser International showed that 69 uses
out of 439 (15.7%) of their M26 Advanced Taser had been a touch-stun application,
with a reported 85.5% success rate. Further figures from Canada have shown that 49
uses out of 113 (43.4%) of the M26 have been touch-stun applications with a reported
89.0% effectiveness.

3. PSDB TESTING
This section describes a number of tests carried out at PSDB on the M26 Advanced
Taser. All of the tests were carried out using three identical models of taser with 21ft
(6.4m) cartridges.
3.1
Accuracy
The M26 employs a single laser sight that is designed to show where the top barb will
land on the target. While a large separation of the barbs is desirable in order to
provide maximum incapacitation, it is also important that both barbs will penetrate the
target or at least attach onto their clothing, otherwise the circuit cannot be completed
and the electricity will not flow through the target. A number of basic accuracy tests
were therefore carried out to determine the position of the top barb relative to the laser
dot and the separation of the two barbs at different distances.
3.1.1

Method

An M26 taser was clamped firmly into a tripod and the device checked to ensure it
was level. A flat cardboard target covered in foil was secured at a set distance from
the taser. With the laser sight turned on, the red dot position was marked on the target
with a spot. A cartridge was inserted into the front of the taser and fired at the target.

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The position of the laser spot was taken as the zero point and the position of the top
barb was measured relative to this. The position of the bottom barb was measured
relative to the top barb.
21ft (6.4m) cartridges were used for each of these tests and tests were repeated at 5,
10, 15 and 20ft (1.5, 3.0, 4.6 and 6.1m). At least 10 cartridges were fired at each of
these ranges. These tests were carried out indoors at room temperature, with no wind
effect and with the taser clamped firmly using a tripod, therefore representing an ideal
situation.
3.1.2

Results

Table 2 shows the results for the testing carried out at PSDB. Values given are the
separation between the top barb and the point of aim (the laser-sighting dot), and the
separation between the top and bottom barbs. The ranges show the maximum and
minimum values for these while the mean gives the average values at each distance.

Distance from
taser to target
5ft (1.5m)
10ft (3.0m)
15ft (4.6m)
20ft (6.1m)
TABLE 2:

Separation between top barb
and laser dot
Range (mm)
Mean (mm)
20 - 55
15 - 135
90 - 140
105 - 410

39
63
109
287

Separation between top barb
and bottom barb
Range (mm)
Mean (mm)
205 - 260
305 - 440
534 - 685
563 - 905

225
378
601
786

Results of Accuracy Tests carried Out at PSDB

At 5ft (1.5m), 9 shots out of 10 resulted in the top barb hitting above the aim point. At
10ft (3.0m), 4 shots out of 10 resulted in the top barb hitting above the aim point. At
15 and 20ft (4.6m and 6.1m), all shots resulted in the top barb hitting below the aim
point.
These results are represented in Figures 4 to 7. These figures show the position of
each of the barbs at each distance as they would fit on a man-sized target with the
outline showing torso, leg and arm areas. The point of aim is taken as the centre of the
chest area just above the nipple line.

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Barb displacement relative to aim point (mm)
5 ft from targe t

100

0
-300

-200

-100

0

100

200

300
Top

-100

Bottom

-200

-300

FIGURE 4:

Position of Taser Barbs at 5ft (1.5m)

Barb displacement relative to aim point (mm)
10 ft from target
300
200
100

-500

-300

0
-100
-100

100

300

500

-200

Top
Bottom

-300
-400
-500
-600

FIGURE 5:

Position of Taser Barbs at 10ft (3.0m)

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Barb displacement relative to aim point (mm)
15 ft from target
200

0
-800

-600

-400

-200

0

200

400

600

800

Top
Bottom

-200

-400

-600

-800

FIGURE 6:

Position of Taser Barbs at 15ft (4.6m)

Barb displacement relative to aim point
20 ft from target
200
0
-1200 -1000 -800 -600 -400 -200
0
-200

200

400

600

800

1000 1200

Top
-400

Bottom

-600
-800
-1000
-1200

FIGURE 7:

Position of Taser Barbs at 20ft (6.1m)

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3.2
Velocity
The velocity of the taser barbs during flight was measured while the accuracy tests
were being carried out. These results are shown in Table 3.
Distance from taser
1m
2m
2.5m
4m
TABLE 3:

Velocity of barbs
36 ± 4 m/s
33 ± 2 m/s
30 ± 1 m/s
22 ± 1 m/s

Change in Velocity of Taser Barbs with Distance

3.3
Electrical Output
A series of tests were carried out at PSDB to determine the electrical output of the
M26 in terms of waveform, current, voltage, pulse-width, energy and power.
Measurements were also made of any changes which occurred to these when an air
gap was incorporated into the circuit (as would be the case if a barb did not penetrate
the skin of the target but instead attached onto their clothing). These tests were
necessary not only to give us a fuller understanding of the taser output, but also to
provide information to an independent medical committee to help them assess the
effects of the taser on the human body. The results provided in this report are not
exhaustive and further analysis of some of the electrical effects is necessary. A more
detailed report of this testing will be prepared for the medical committee to provide
them with the information they require.
The electrical signal produced by a taser is very different from the signal produced
from household electricity. Household electrical appliances have a continuous
alternating current (AC) with a peak voltage of 340V, a root mean square (rms)
voltage of 240V and a frequency of 50Hz (i.e. 50 oscillations per second). This type
of waveform is represented in Figure 8.

FIGURE 8:

Waveform for Household Electricity

The waveform produced by the taser is very different to this. The taser operates by
charging up and then instantaneously discharging a capacitor. The result is a series of
pulses of very high voltage and very short duration. The pulses last only a few
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Voltage (V)

microseconds, while the pulse separations are relatively long in comparison, lasting
tens of milliseconds. In current commercial devices, there are between 10 and 20
pulses per second. The high potential difference (or voltage) is necessary to allow the
electricity to jump across an air gap, such as would be the case if the barbs attached
onto a subject’s clothing, rather than penetrating their skin. The power (wattage)
relates to the rate at which the energy is transferred. Figure 9 shows the typical
waveform that is produced from a taser discharge – only one pulse is represented in
this figure.
35000
30000
25000
20000
15000
10000
5000
0
-5000
-10000
-15000
-20000
0

5

10

15

20

25

30

Time (µS)
FIGURE 9:

Waveform for Taser Output

Another important distinction between the mains electricity and the output from the
taser is the availability of energy. Each pulse from the taser represents a discrete
package of energy of a more or less constant value, therefore the number of sparks or
packages per second will be the maximum power delivered. Power from the mains is
not limited in this way, the current that can be drawn (which is proportional to the
energy) is not limited to discrete packages and will increase until the load (or
resistance) is met or the fuse or safety device operates.
3.3.1

Method

The electrical output of the M26 was measured in the following way: a potential
divider of total resistance Rt was placed across the ends of the barbs, which had been
ejected from the taser cartridges, in order to complete the circuit. The total resistance
was intended to simulate that of the human body, but since this resistance is highly
variable, a range of values was chosen for measurement. The output pulse from the
device was discharged across Rt and the output voltage measured using an
oscilloscope.
Measurements were made of the change of current and voltage with total resistance.
These tests were then repeated with an air gap of a certain distance incorporated into
the circuit. The effects of an air gap on the waveform must be considered if the taser
barbs do not penetrate the skin of a subject, but instead attach onto their clothing. In
this case the electricity can still arc across the gap and be passed through the subject’s
body (depending on the distance of the air gap). In these tests, a gap was created
between one of the barbs and a potential divider of total resistance Rt; the gap was

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then increased in 5mm increments. These measurements were repeated using different
values of Rt.
Measurements were also taken of the maximum air gap that could be introduced into
the circuit before the electricity started to arc across the electrodes on the head of the
taser, rather than through the circuit. The limit of the gap was taken as the distance at
which approximately half of the discharges sparked between the two electrodes on the
taser rather than passing through the circuit. These measurements were repeated using
different values of Rt.
3.3.2

Results

Figures 10 and 11 show the changes in voltage and current respectively with the
change in total load resistance, Rt.
70000

60000

Peak Voltage (V)

50000

40000

30000

20000

10000

0
0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Load Resistance (Ω)

FIGURE 10:

Variation of Peak Voltage from M26 Taser with Changing Load
Resistance

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16

14

Peak Current (A)

12

10

8

6

4

2

0
0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Load Resistance (Ω)

FIGURE 11:

Variation of Peak Current from M26 Taser with Changing Load
Resistance

From these graphs, it can be seen that the peak output voltage increases as the
resistance within the circuit increases, with the often-quoted value of 50,000V
occurring at a total resistance of approximately 4,000 ohms. The peak current, on the
other hand, remains essentially constant at 11.5-14 amps, despite changes in the total
resistance.
Figure 12A-C shows the change in waveform that results when an air gap is
incorporated into the circuit at a set resistance. The resistance chosen was 2,200 ohms
and the graphs represent changes in peak voltage with time.
Graph A shows the output when there is no air gap incorporated into the circuit.
Graph B shows the output when an air gap of 5mm is incorporated into the circuit and
graph C shows the output for an air gap of 10mm.
By comparing graphs A-C, it can be seen that there is an increase in the voltage of the
spike observed at the front of the first pulse as the size of the air gap is increased. The
presence of a spike in graph A can be observed, even with no deliberate air gap
incorporated into the circuit. The reason for this may be that the current jumps across
from the taser electrodes on the taser body to the wires within the cartridge.
This large spike in front of the pulse has a much higher peak voltage than the main
pulse, although it only lasts for a very short period of time. It is as yet unknown how
much difference, if any, this will have on the effects of the electricity on the human
body. This information, along with all the other electrical output data, will be passed
to the medical committee when they make their assessment.

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100000

Voltage (V)

80000
60000
40000
20000
0
-20000
-40000
0

5

10

15

20

25

30

Time (µS)

D 7DVHU 2XWSXW ZLWK  RKP /RDG $LU *DS

PP

100000
80000

Voltage (V)

60000
40000
20000
0
-20000
-40000

0

5

10

15

20

25

30

Time (µS)

E 7DVHU 2XWSXW ZLWK  RKP /RDG $LU *DS ≈ PP
100000

Voltage (V)

80000
60000
40000
20000
0
-20000
-40000
0

5

10

15

20

25

30

Time (µS)

F 7DVHU 2XWSXW ZLWK  RKP /RDG $LU *DS ≈ PP
FIGURE 12:

Change of Voltage with Time for Varying Air Gap Distance

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It should be noted that the values plotted in figures 10 and 11 are for the peak voltage
and current of the main pulse, and not the spike in front of this pulse.
Figure 13 shows the size of the air gap that allows approximately 50% of discharges
to arc across the taser electrodes rather than through the circuit with varying
resistance.
Air Gap Distance at which 50% of the Charge Arcs Over the Taser
35

30

Arcing Point (mm)

25

20

15

10

5

0
0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Load Resistance (Ω)

Figure 13:

Change in Arcing Gap Distance with Load Resistance

It is clear from this graph that at resistances of 500 ohms and greater, the maximum
air gap that allows approximately 50% of the current to flow through the circuit is
20mm (less than an inch). It is useful to compare these results to those found by Sgt
Laur - he found that a spark gap of 2.25inch (57mm) was possible for the same
cartridges. His tests were carried out by placing two barbs together so that they were
pointing at each other. The darts were then separated at 0.25 inch (6.3mm)
increments, the taser activated and the arc between the barbs observed. The main
difference between his test and the PSDB test is that no resistance was present within
the circuit used by him. We can see from Figure 13 that a very low resistance within
the circuit will allow a much greater spark gap to exist. The PSDB test is more
realistic as the resistance of the human body will always be an important factor in
taser usage.
3.4
Drop Tests
These tests were carried out to determine what kind of treatment the M26 could
withstand while still remaining in a working condition. The drop test involves
dropping the item under examination from a height of 2m onto a steel plate and
observing any damage that occurs.

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3.4.1

Method

A taser, with a 21ft (6.4m) cartridge inserted into the firing bay, was dropped from a
height of 2m onto a steel plate. The test was repeated eight times using the same taser
held at different angles and with a different cartridge inserted each time. Any damage
to the taser or cartridges was noted. Following the drop, and for those cartridges still
intact, each cartridge was fired from an intact taser and the position of the barbs noted
along with any unusual results.
This test was then repeated for the cartridges alone by dropping them from a height of
2m onto a steel plate. A new cartridge was used for each drop and four cartridges
were dropped in total. Any damage to the cartridges was noted. Following the drop,
and for those cartridges still intact, each cartridge was fired from an intact taser and
the position of the barbs noted along with any unusual results.
3.4.2

Results

When the taser with a cartridge attached was dropped, the cartridges sometimes fell
out of the firing bay (3 times out of 8). On one of these occasions the striped ‘doors’
on the front of the cartridge became detached, although the rest of the cartridge
remained intact. This test was repeated eight times using the same taser but with a
different cartridge each time. When these cartridges were fired afterwards, the
position of the barbs fell within the range expected at that distance and no other
problems were noted.
As regards the effects on the taser itself when dropped in this way, a number of
problems occurred:
•
In the first two drops, the battery catch at the bottom of the taser loosened and
had slid forward a little, although the batteries remained firmly in place;
•
After the third drop, the taser split down the middle at its rear and after this the
battery catch could no longer be properly attached;
•
After the fifth drop the safety catch fell off from the right hand side of the
taser;
•
After the sixth drop, the battery indicator button fell off.
Although little damage occurred to the cartridges when attached to the taser and then
dropped, this was not the case when the cartridges were dropped on their own. Four
separate cartridges were dropped from a different angle each time:
•
The first cartridge suffered no damage when dropped although the position of
the top barb when fired was slightly outside the range that would expected at
that distance. There were no other problems;
•
When the second cartridge was dropped the striped ‘doors’ came off, both
wires came out and unravelled (one wire was found to be torn in two) and one
of the barbs was ejected;
•
When the third cartridge was dropped the striped ‘doors’ came off, one wire
came out and unravelled and one of the barbs was ejected;
•
When the fourth cartridge was dropped the striped ‘doors’ came off, both
wires came out and unravelled but the barbs were not ejected;
Three out of four cartridges were unusable after they had been dropped.

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3.5
Clothing Penetration
The intention of these tests was to determine whether a selection of clothing materials
could prevent the taser barbs from either penetrating through them or attaching on to
them. 21ft (6.4m) taser cartridges were fired at a mannequin dressed in a variety of
different clothes at a distance of 5ft (1.5m).
Seven different types of material were used for these tests: a heavy waterproof anorak,
cotton overalls, a polyester reflective vest, a leather jacket and three types of body
armour: dual purpose, covert (ballistic only) and ballistic. Two cartridges were used
on each of these materials. The results for these tests are shown in Table 4.
With the exception of the zip, none of the materials tested here stopped the barbs from
at least partly penetrating and attaching onto the material.
3.6
Flammability
The aim of these tests was to determine the risk of ignition if a taser is fired at a
person with flammable liquid on their clothing. The liquid used in these tests was
methyl isobutyl ketone (MIBK), the solvent present in the CS sprays used by the UK
police.
3.6.1

Method

A full canister of Alsetex/Primetake MIBK only (30ml) was sprayed at a mannequin
wearing a standard jogging sweatshirt (material is 65% polyester, 35% cotton). The
mannequin was first covered in foil to allow conduction of the electricity through the
barbs. The entire canister was sprayed at the front of the sweatshirt. A taser cartridge
was then fired at the mannequin from a distance of 5ft (1.5m). This was repeated a
total of seven times with a new, but otherwise identical, sweatshirt used each time.
3.6.2

Results

In five of the occasions, there was no ignition at the mannequin, although sparking
was observed at the barbs attached to the mannequin, indicating that electricity was
flowing through the circuit. On the other two occasions, however, ignition occurred at
the mannequin after the barbs penetrated the sweatshirt. On one occasion the
sweatshirt ignited as soon as the barbs attached to it, and on the other occasion a
second or two passed before the flames began. In both cases, the flames produced
were severe and engulfed the entire top half of the mannequin, including the head.
It is clear from these tests therefore that there is a serious risk of ignition if the taser is
fired at a target that has a flammable solvent on their clothing.
3.7 Extreme Temperature
The aim of these tests was to determine whether the M26 would still be in a working
condition after being subjected to extremes of heat and cold.
3.7.1

Method

Two tasers with cartridges inserted were placed in an oven at +50OC for a minimum
of 12 hours. One of the tasers contained Energizer NiMH rechargeable batteries and
the other contained Duracell Ultra alkaline batteries (both sets fully charged). A
number of spare cartridges were also placed in the oven. After this period, the tasers
were removed, one at a time, and the cartridge fired at a target to determine if the
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First Cartridge
Bottom Barb

Clothing
Material
Heavy
waterproof
anorak

Top Barb

Cotton overalls

Fully penetrated all layers of
the overalls, including the
double velcro layer where the
overalls fastened.
Fully penetrated the single
layer of material and the
reflective band.
Fully penetrated two layers Fully penetrated two layers of
of leather (jacket folded) but leather (jacket folded) but not
not through third layer – through third layer – barb
barb securely attached.
securely attached.

Polyester
reflective vest
Leather jacket

All
armours

TABLE 4:

Hit the zip of the jacket and
did not penetrate or attach
onto it. The barb actually
rested on top of the zip
puller, although if this had
not been present the barb
would have fallen away.
Fully penetrated all layers of
the overalls, including the
double velcro layer where
the overalls fastened.
Fully penetrated the single
layer of material.

body Barb penetrated armour up
to the point where the
diameter of the barb
increased. Securely attached
to armour.

Penetrated the first outer layer
of the jacket but failed to
completely penetrate the inner
layer, although barb was firmly
attached to the jacket.

Top Barb

Second Cartridge
Bottom Barb

Penetrated the first outer
layer of the jacket but failed
to completely penetrate the
inner layer, although barb
was firmly attached to the
jacket.

Penetrated the first outer
layer of the jacket but failed
to completely penetrate the
inner layer, although barb
was firmly attached to the
jacket.

Fully penetrated the single Penetrated the outer layer of
layer of cotton overall.
cotton and one layer of
velcro, then lodged in the
second layer of velcro.
Fully penetrated the single Fully penetrated the single
layer of material.
layer of material.

Penetrated one layer of
leather,
attached
onto
second layer (struck at
fastening area of jacket with
double layer).
Barb penetrated armour up to Barb penetrated armour up
the point where the diameter of to the point where the
the barb increased. Securely diameter of the barb
attached to armour.
increased. Securely attached
to armour.

Fully penetrated one layer of
leather.

Barb penetrated armour up
to the point where the
diameter of the barb
increased. Securely attached
to armour.

Behaviour of Taser Barbs when Fired at Different Materials

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system worked correctly. These tests were repeated at –20OC after the tasers had been
kept in a freezer.
3.7.2

Results

i) At +50OC
At this temperature, the laser sights and battery indicators did not work on either taser.
The tasers themselves were also incapable of being fired. These problems were not
caused by the batteries as these worked as normal when placed in a room temperature
taser. Furthermore, using room temperature batteries in the hot taser resulted in the
same problems as before.
The problems were also not related to the cartridges since six cartridges, each also
held at +50OC, were fired from a room-temperature taser; all cartridges fired as
normal with no problems, and the barbs fell within the range to be expected at that
distance.
As the tasers were allowed to cool back to room temperature their performance
gradually improved. During the first hour or so there seemed to be a problem with the
connections within the device: the tasers could be fired on some occasions but not
consistently. After an hour or so, both tasers were capable of firing every time,
although the laser dot did not return to full brightness. After 24 hours the lasers had
returned to normal.
ii)
At –20OC
At this temperature, the laser dots and battery indicators were functioning, but the
tasers were incapable of firing. For the taser containing the NiMH batteries, two
distinct laser dots were observed at the target, while for the taser containing the
Duracell Ultra batteries, the laser spot was large, dim and unfocussed.
As the tasers were allowed to return to room temperature their performance gradually
improved. After half an hour the taser would fire on some occasions but not
consistently. After an hour or so, both tasers were capable of firing every time,
although the laser dot did not return to full brightness. After 24 hours the lasers had
returned to normal.

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