[0001] The present invention relates to a system for dispersal of forensic materials, more
particularly forensically coded solid materials such as may be used in the identification
of property following theft.
[0002] Solid materials tor identifying property may comprise minute circles of film or metal
which are printed or etched in miniature with an identifying code. Alternatively,
the solid materials may comprise a specific mixture of rare earth materials. These
are used to mark property, in order that the property may be identified and linked
to its rightful owner, usually following loss or theft. Such materials will be described
below as "forensic particulate material."
[0003] Pyrotechnic smoke-dye devices are also known for use in marking property. These may
be activated automatically in the event of theft, and mark with a coloured dye the
property being stolen, for example bank notes.
[0004] Other security devices are known which, in the event of an attempted theft, create
a volume of white smoke or glycol-based fog to hinder theft of property by severely
restricting visibility in a room or other region adjacent the device.
[0005] It is an object of the present invention to provide a device for dispersing forensic
particulate material in conjunction with other security devices, and to provide security
apparatus equipped with such a dispersion device.
[0006] According to a first aspect of the present invention there is provided a device to
disperse forensic particulate material as herein defined, comprising a charge of forensic
particulate material, sachet means adapted to contain said forensic particulate material
and pyrotechnic fuse-head means located within said sachet means and adapted to initiate
dispersal of the forensic particulate material.
[0007] When the fuse-head means is activated, the sachet means bursts and the forensic particulate
material is released.
[0008] The sachet means may be provided with at least one zone of increased frangibility.
[0009] According to a second aspect of the present invention, there is provided security
apparatus comprising a device as described in the first aspect above.
[0010] Said security apparatus may be adapted to generate smoke, optionally dyed smoke,
fog, mist, vapour or the like.
[0011] The fuse head means of said device may be programmable to be activated before activation
of the security apparatus, for example before production of smoke, fog, or the like
therefrom.
[0012] A smoke composition, fog generator or the like may subsequently be activated and
the expansion or migration of gases discharges the forensic material, for example
over bank notes and/or the clothing and body of a perpetrator.
[0013] A specific embodiment of the invention will now be more particularly described by
way of example and with reference to the accompanying drawings in which:
Figure 1 shows a pyrotechnic smoke-dye package device embodying the present invention;
Figure 2 shows the package shown in Figure 1 at the moment rupture is initiated; and
Figure 3 shows the package shown in Figure 1 following rupture, exploding to release
forensic material and smoke.
[0014] Referring now to the Figures, a dispersal device embodying the present invention
comprises a fuse head 1, a pyrotechnic smoke-dye composition 2, and a compartment
containing solid forensic particulate material 3. All the above are contained within
a sachet 4 having a plurality of frangible zones 5, preferably located remotely from
the pyrotechnic composition 2. The fuse head 1 is preferably located adjacent the
frangible zones 5 of the sachet 4, and is linked to the pyrotechnic smoke-dye composition
2 by an elongate fast-burning fuse 6.
[0015] To disperse the forensic particulate material 3, the pyrotechnic smoke-dye composition
2 is set off by conventional means (typically in response to some form of alarm system).
This initiates combustion of the fuse 6, which rapidly burns along its length and
sets off the fuse head 1. The fuse head 1 contains a small pyrotechnic or explosive
charge which bursts open the sachet 4, for example by breaking the frangible zones
5 (or in other embodiments by blowing open flaps usually biassed closed, or by blowing
open a mouth of the sachet 4 normally held closed by a weak adhesive or by the configuration
of the sachet 4 itself). The fuse head 1 also shakes up and disperses the particles
of the forensic particulate material 3 within the compartment (Figure 2).
[0016] Meanwhile, the pyrotechnic smoke-dye composition 2 is burning to generate a copious
stream of dyed smoke 7, which passes along the sachet 4 to exit through the frangible
zones 5, etc. This stream of dyed smoke 7 entrains the dispersed forensic particulate
material 3, which is thus projected out of the sachet 4 with the smoke 7.
[0017] The smoke-dye 7 will stain its surroundings, for example dyeing a bundle of banknotes
in which it has been secreted, to prevent their use by a thief. A drawback of existing
smoke-dye marking systems is that it may not be possible to link stained bank notes,
recovered subsequently, to a particular theft. However, in the present invention,
a plurality of forensic particles will also be deposited on the bank notes or other
property. Each batch of forensic particulate material used in a device bears a unique
identification means, and so one may recover a forensic particle from a stained piece
of property, read off the identification means, and check back to where that particular
batch was used. It is hence possible to link the recovered property to a specific
event such as a theft. If the smoke-dye 7 contacts the person or clothes of a thief,
then the thief can similarly be linked to the specific theft by recovering and identifying
forensic particles 3 from the smoke-dye stains.
[0018] In an alternative embodiment, the pyrotechnic smoke-dye composition 2 and the fuse
head 1 may be separately ignited. It is preferable that the fuse head 1 bursts before
the composition 2 has begun to generate significant volumes of smoke. For example,
one may program the fuse head 1 to detonate two seconds before the composition is
ignited:
[0019] A similar sachet (not shown) .may be used in conjunction with an otherwise conventional
fogging security apparatus. These apparatus fill a room or region with an opaque cloud
of white smoke or fog, to obscure vision and impede or halt the progress of a crime
such as a theft or a brcak-in. The fog is typical a cloud of glycol vapour.
[0020] As above, a fuse head 1 is detonated to disperse the forensic particulate material
3. The forensic particles 3 are then entrained into the flow of smoke or fog being
projected out of the fogging device.
[0021] For existing fogging devices, it is possible for a perpetrator causing triggering
of the device to slip away under cover of the fog. The theft or break-in is thwarted,
but the perpetrator may escape, With the system described above, the fog contains
numerous forensic particles 3 which will be deposited on the person and/or clothing
of the perpetrator. If a forensic particle 3 can be found on a suspect's person or
possessions and tracked back to the particular batch discharged by the fogging device,
the presence of the suspect can be demonstrated.
1. A device to disperse forensic particulate material as herein defined, comprising container
means (4) holding a charge of said forensic particulate material (3) characterised in that said device comprises pyrotechnic detonator means (1) located within the container
means (4) and adapted to initiate dispersal of the forensic particulate material (3).
2. A device as claimed in claim 1, characterised in that activation of the detonator means (1) opens exit means (5) of the container means
(4).
3. A device as claimed in claim 1 or claim 2, characterised in that the container means (4) is provided with at least one zone (5) of increased frangibility
breachable by the detonator means (1).
4. A device as claimed in any one of the preceding claims, characterised in that the container means (4) further comprises a pyrotechnic composition (2), ignitable
to generate smoke (7), optionally a smoke-dye composition to generate dye-containing
smoke.
5. A device as claimed in claim 4 characterised in that it comprises common ignition means for the detonator means (1) and the pyrotechnic
composition (2).
6. Security apparatus characterised in that it comprises a device to disperse forensic particulate material as claimed in any
one of the preceding claims.
7. Security apparatus as claimed in claim 6, characterised in that it is adapted to project smoke, vapour or the like having said forensic particulate
material (3) entrained therein.
8. Security apparatus as claimed in claim 7, characterised in that the detonator means (1) of the dispersal device is adapted to be activated prior
to generation of said smoke, vapour or the like.
9. Security apparatus as claimed in any one of claims 6 to 8, characterised in that it comprises means to generate a substantially opaque fog of droplets, such as glycol
droplets.
10. Security apparatus as claimed in any one of claims 6 to 8, characterised in that it comprises a pyrotechnic smoke composition, ignitable to generate smoke.
11. Security apparatus as claimed in claim 10, characterised in that said composition comprises a pyrotechnic smoke-dye composition, ignitable to generate
smoke-dye cloud means adapted to stain surfaces contacted thereby.