[0001] The invention relates to a fire protection device which is gas-permeable in a non-activated
condition, as well as a storage space for highly inflammable and volatile materials,
provided with such a fire protection device.
[0002] In the art, there is an increasing need for safe storage of materials that are highly
inflammable and/or volatile, and/or materials from which highly inflammable and/or
volatile materials can be released. On account of the above-mentioned properties,
the handling of these materials must always be done with the necessary care and therefore
be left exclusively to experts. In practice, however, it is necessary that a certain
stock of the material mentioned be present in certain spaces, even if the materials
are not used directly. In that case, to limit the risk of accidents as far as possible,
the materials must be stored in a so-called fire-proof chamber or vault. As far as
possible, this prevents the materials mentioned from exploding or catching fire when
a fire breaks out through whatever cause. Another purpose of such a fire-proof chamber
or vault is to prevent the formation of an explosive or inflammable mixture as a result
of possible leakage of the materials mentioned from their respective container, for
which purpose the chamber or vault mentioned is ventilated to a sufficient degree.
This means, however, that the interior of such a chamber or vault is provided with
an inflow of outside air, i.e., oxygen. A situation that might occur is the situation
where the stored gases release a gas, for instance due to a container being improperly
sealed, which gas, mixed with ambient air, is extracted and, through one cause or
another, ignited.
[0003] Typically, the flame extension rate, or the propagation rate of the flame front,
upon ignition of a gas mixture is higher than the flow rate of the relative gas, in
particular when that flow rate is only provided by ventilation, with the result that
a flame starting outside the chamber or vault can reach the interior of the chamber
or vault against the gas flow and ignite or even explode the materials present there.
[0004] An important task of the chamber or vault mentioned is therefore to prevent the flame
of the gas mixture burning outside the chamber from reaching the materials in the
chamber.
[0005] In the art, means are already known for preventing such "flashback" of the fire.
Such means will hereinafter be referred to as flame-arresting means and are all based
on the principle, known with respect to miner's lamps, of a metal wire mesh or grid
arranged in the gas stream. A flame front present on the outflow side of such a wire
mesh or grid cannot pass the grid; the flame burns on the grid, so to speak.
[0006] Although in practice a flame-arresting grid does indeed have the above-mentioned
effect, major problems arise in practice when the supply of the inflammable gas mixture
is maintained for some time, for instance in the case of a leaking container. In such
a case, the flame-arresting grid may lose its flame-arresting activity. The principal
reason for this is that the grid is heated as a result of the flame burning continuously
against the grid. Owing to the increasing temperature, the grid may melt and thereby
lose its function. In some cases it may even happen that, even before the grid melts,
the heated grid ignites the gas mixture on the inflow side of the grid. In the case
of prolonged fire, therefore, the known fire protection devices do not have any fire-resisting
effect.
[0007] The object of the invention is to provide a fire protection device that combines
good flame-arresting activity with good fire-resisting activity, so that the above-mentioned
risk is absent, at least reduced.
[0008] To that end, a fire protection device which is gas-permeable in a non-activated condition
comprises, according to the invention, the combination, arranged in series, of at
least one flame-arresting element, preferably a metal grid, and at least one fire-resisting
element, which is preferably designed to automatically block a gas stream therethrough
in case of fire.
[0009] Although in principle any gas stream shut-off element is suitable for this purpose,
a preference is expressed for elements that react to an increase in temperature. One
example of such an element is a grid-shaped construction, for instance in the form
of a honeycomb, plates, spirals or the like, of a material that foams or swells upon
an increase in temperature and thereby closes off the passages of that grid. An example
of such a material is known under the name of Palusol, a registered trade mark of
BASF. Another example of such a material is known under the name of Fireblock, a registered
trade mark of Dufaylite Development, which material is described in DE-A-2.605.720.
Thus, it is possible to obtain a very compact device with excellent flame-arresting
and fire-resisting properties in almost any situation.
[0010] It is noted that EP-A-0.090.635 describes a fire-barrier with a layered structure
of a heat reflective material, an endothermal material, and a thermally intumescent
material. This known device is not permeable to gas, and functions merely to protect
an object such as a hose against heat from a fire by reflecting the heat radiation
and by providing a thermal insulation.
[0011] Although a combination of a flame-arresting grid and a fire valve that automatically
reacts thermally, as described hereinabove, already provides an improvement over known
flame-arresting means, in practice problems may still arise here. A first problem
may be, for instance, that it is not known beforehand on which side of the flow passage
the flame will start. It will be clear that in case a fire starts in the chamber,
it is equally desired that the fire be prevented from spreading to the outside.
[0012] It may further be desired to increase the quickness of reaction of the fire valve.
When the fire valve is located on the side of the flame-arresting grid remote from
the flame, the fire valve will not perform its function until, after a certain amount
of time has lapsed, the heat of the flame has also heated the grid on the other side
thereof. On the other hand, when the fire valve is located on the flame side of the
grid, the reaction of the fire valve can be relatively quick owing to the direct action
of the flame, but the chances are that the fire valve will be damaged by the flame
itself or even melts.
[0013] Preferably, therefore, the device according to the invention consists of at least
three layers, with the separate layers alternately having different functions, i.e.,
a flame-arresting or a fire-resisting function. If a device that is active on two
sides is to be provided, for instance because it is not known beforehand on which
side a fire may start, it is recommended that the device be provided with at least
two flame-arresting layers with at least one fire-resisting layer provided therebetween.
The simplest construction that meets this requirement comprises three layers which
are, successively, flame-arresting, fire-resisting and flame-arresting.
[0014] If the device is to react very quickly to the presence of a flame by shutting off
the gas stream at least partly, it is recommended that the device according to the
invention be made so as to comprise at least three layers, with, starting from the
side where the flame is expected to begin, a first fire-resisting layer, then a flame-arresting
layer, and a second fire-resisting layer. In such a construction, the first fire-resisting
layer, facing the flame, will react very quickly, but when this layer is affected
by the presence of the flame, its task can be taken over by the third layer, i.e.,
the second fire-resisting layer, which is separated from the flame by the second layer,
i.e., the flame-arresting layer.
[0015] If so desired, the device according to the invention can contain several alternate
layers.
[0016] It is also possible to arrange a detector in the device according to the invention,
which detector reacts to an increase in temperature to above a predetermined level
by shutting off a valve operating mechanically, electrically, electro-mechanically
or otherwise, so as to shut off the gas stream completely with 100% certainty.
[0017] Hereinafter, the invention will be further clarified through a discussion of preferred
embodiments, with reference to the drawings, in which:
Fig. 1 is a section of a workshop including a storage space for chemicals according
to the invention;
Fig. 2 is a perspective view of a storage chamber to be arranged as a loose element;
Fig. 3 is a partial section of the door of the chamber shown in Fig. 2, taken on the
line III-III;
Fig. 4 is a perspective view of a simple embodiment of a fire protection device according
to the invention;
Fig. 5 is a schematic cross-section of a fire protection device according to the invention
having flame-arresting activity on two sides; and
Fig. 6 is a schematic cross-section of a fire protection device according to the invention
having fire-resisting activity on two sides.
[0018] Fig. 1 shows a workshop 1 in which a separate space 2 has been built for storing
chemicals (not shown for the sake of clarity). However, the invention also relates
to storage spaces which are to be arranged as loose elements, such as a chamber or
vault.
[0019] The chamber, vault or built-in storage space can be intended for the storage of volatile
materials, such as thinner and/or other chemicals. The storage space is ventilated,
to which end, in the situation shown in Fig. 1, a fan 4 arranged on the roof 3 of
the workshop 1 is connected via a tube 5 with the ceiling 6 of the storage space 2.
The storage space 2 is arranged adjacent an outer wall 7 of the workshop 1 and communicates
via two tubes 8, 9 with the outside air. When the fan 4 is in operation, fresh air
enters the storage space 2 via the tubes 8, 9, as indicated by the arrows P1 and P2,
while air to be extracted, which may be mixed with gas originating from the volatile
materials mentioned, leaves the storage space 2 via the tube 5.
[0020] According to the invention, the storage space 2 is provided with fire protection
devices 21, 22 and 23 in the air supply channels 8 and 9 and the air extraction channel
5, respectively.
[0021] It is noted that in the situation described the interior of the storage space 2,
when the door giving access to it is closed, is not in communication with the interior
space of the workshop 1. However, in the case of a storage chamber to be arranged
as a separate element, this may well be the case when a separate supply of outside
air cannot be realized. Fig. 2 shows a perspective view of such a loose storage chamber
10 with an entrance door 11, with ventilation taking place, not in any forced manner
but in a natural manner via two openings 12 and 13 provided in the upper and in the
lower part of the door 11, respectively. According to the invention, the storage chamber
10, too, is provided with fire protection devices in the openings 12 and 13, as shown
in Fig. 3 in the partial section of the door 11.
[0022] The fire protection devices 14 according to the invention utilized in the chamber
10 comprise a fire-resisting element 15 and a flame-arresting element 16, which are
arranged in series with regard to the air stream through the relative opening. Further,
on the outside of the door 11 an ornamental grid 17 of the Louvre type is arranged,
which does not have any fire protection function. For the sake of clarity, the essential
parts of the fire protection device 14 according to the invention are shown in perspective
in Fig. 4. The shape of the fire-resisting element 15 and the flame-arresting element
16 can be rectangular or round, adapted to the shape of the openings in the door or
the channels. The thickness of the flame-arresting element 16 will generally be a
few millimeters; the thickness of the fire-resisting element 15 will generally be
a few centimeters.
[0023] The flame-arresting element 16 can be made of metal gauze or a metal grid. A material
that has been found to be particularly suitable and is to be preferred accordingly,
is a metal foam, for instance the metal foam known under the name of Recemat (registered
trade mark of SEAC International B.V.).
[0024] A preferred embodiment of the fire-resisting element 15, as shown, likewise has a
grid-shaped construction, for instance in the form of a honeycomb, plates, sprirals
or the like, of a material that foams or swells up in reaction to an increase in temperature,
and thereby closes off the passages of the grid. An example of such a material is
known under the name of Palusol, a registered trade mark of BASF. A material that
has been found to be particularly suitable and is to be preferred accordingly, is
known under the name of Fireblock (registered trade mark of Dufaylite Development).
[0025] The operation of the fire protection device 14 according to the invention is as follows.
When highly inflammable gases that are present or are being released in the chamber
10 leave the chamber through the opening 12 and/or 13, while being mixed or having
been mixed with ambient air, in principle a fire hazard arises. When, by whatever
cause, the mixture starts to burn outside the chamber 10, the flame front will spread
very rapidly in the direction of the openings 12, 13 of the chamber 10. There the
flame contacts the flame-arresting element 16 of the fire protection device 14 according
to the invention, which, as is known, cannot be passed by the flame. This accordingly
prevents the materials and/or gases present in the chamber from being ignited or even
exploded.
[0026] Under the influence of the increase in temperature caused by the flame, the fire-resisting
element 15 is activated so as to close off the gas through-flow opening and thereby
deprive the flame of its fuel supply. In the preferred embodiment described, this
is achieved in that the material of the fire-resisting element 15 foams or swells
up and thereby closes off the passage openings of the grid-shaped structure.
[0027] Thus, by using the above-described preferred materials and preferred construction,
a very compact fire protection device is provided, having excellent flame-arresting
and fire-resisting properties in practically any situation. As appears from Figs 3
and 4, in the application shown there, the fire protection device 14 according to
the invention is mounted in the air openings 12 and 13, such that the flame-arresting
element 16 faces outwardly and the fire-resisting element 15 is located on the side
of the interior of the chamber 10, i.e., on the side of the chemicals. Depending on
the use and the desired effect, the fire protection device 14 according to the invention
can also be mounted in reversed position, i.e., with the flame-arresting element 16
on the side of the chemicals.
[0028] The fire protection devices 21, 22, and 23 for the storage space 2 can have the same
construction as the above-described fire protection device 14. An improved operation
is obtained, however, with a fire protection device consisting of at least three layers,
with the separate layers alternately having different functions, i.e., a flame-arresting
or a fire-resisting function. If a device that is active on two sides is to be provided,
for instance because it is not known beforehand on which side the fire may start,
the outer layers of the thus improved fire protection device are of flame-arresting
design, with at least one fire-resisting layer provided therebetween. The simplest
construction that meets this requirement is illustrated in Fig. 5. The fire protection
device 30 shown schematically there comprises, successively, a first flame-arresting
element 31, a first fire-resisting element 32 and a second flame-arresting element
33.
[0029] In the case where the element is desired to react very quickly to the presence of
a flame by shutting off the gas stream at least partly, the thus improved fire protection
device 40 according to the invention comprises at least three layers with, starting
from the side where the flame is expected, a first fire-resisting element 41, a flame-arresting
element 42, and a second fire-resisting element 43, as schematically shown in Fig.
6. With such a construction, the first fire-resisting element 41 facing the flame
will react very quickly to the contact with the flame and very quickly close off the
gas passage at least partly. However, when the first fire-resisting element 41 is
affected by the presence of the flame, the task thereof is taken over by the third
layer, i.e., the second fire-resisting element 43, which is separated from the flame
by the second layer, i.e., the flame-arresting element 42, so that the flame cannot
reach the second fire-resisting element 43.
[0030] If so desired, the fire protection device according to the invention can contain
several alternate layers.
[0031] It will be clear to those skilled in the art that it is possible to change or modify
the embodiment of the device according to the invention shown, without departing from
the inventive concept of the invention or the scope of protection as defined in the
appended claims. Thus, it is for instance possible to arrange a detector in the device
according to the invention, which reacts to an increase in temperature to above a
predetermined level by shutting off a valve operating mechanically, electrically,
electro-mechanically or otherwise, so as shut off the gas stream completely with 100%
certainty.
1. Fire protection device (14), suitable for placement in a gas passage opening (12;
13) in a wall (11), the device having a non-activated condition wherein the device
is permeable for a gas stream flowing through said passage; the device comprising
a fire-resisting element (15) which has the shape of a grid defining gas flow openings,
the grid having a property of, in response to an increase in temperature, closing
said gas flow openings such that said gas stream is blocked in an activated condition;
characterised by a flame-arresting element (16),
said flame arresting element and said fire-resisting element (15) being arranged in
series with regard to said gas stream.
2. Fire protection device according to claim 1, wherein the flame-arresting element (16)
is made of a metal gauze or metal grid.
3. Fire protection device according to claim 1, wherein the flame-arresting element is
made of a metal foam.
4. Fire protection device according to any of claims 1-3, comprising at least three layers
(31, 32, 33; 41, 42, 43), wherein the separate layers alternately have different functions,
i.e. a flame-arresting or fire-resisting function.
5. Fire protection device according to claim 4, wherein the device has three layers,
which, successively, are flame-arresting, fire-resisting, and flame-arresting.
6. Fire protection device according to claim 4, wherein the device has three layers,
which, successively, are fire-resisting, flame-arresting, and fire-resisting.
7. Storage space (2; 10) having at least one wall (6; 11) with at least one gas passage
opening (5; 12, 13), wherein a fire protection device (23; 14) according to any of
the previous claims is provided in said at least one gas passage opening (5; 12, 13).
8. Storage space according to claim 7, wherein the flame-arresting element (16) is directed
towards the inside of the storage space and the fire-resisting element (15) is directed
towards the outside of the storage space.
9. Storage space according to claim 7, wherein the fire-resisting element (15) is directed
towards the inside of the storage space and the flame-arresting element (16) is directed
towards the outside of the storage space.
1. Brandschutzvorrichtung (14) für die Anordnung in einer Gaskanalöffnung (12, 13) in
einer Wand (11), wobei die Vorrichtung einen nicht aktivierten Zustand, in welchem
sie für einen Gasstrom durchlässig ist, der durch den Kanal strömt, und ein Feuerwiderstandselement
(15) aufweist, welches die Form eines Gitters hat, das Gasstromöffnungen bildet, und
das Gitter die Eigenschaft hat, ansprechend auf eine Temperaturerhöhung die Gasstromöffnungen
zu schließen, so daß der Gasstrom in einem aktivierten Zustand blockiert ist, gekennzeichnet
durch ein Flammensperrelement (16), wobei das Flammensperrelement und das Feuerwiderstandselement
(15) hintereinander bezüglich des Gasstroms angeordnet sind.
2. Brandschutzvorrichtung nach Anspruch 1, bei welcher das Flammensperrelement (16) aus
einem Metallnetz oder Metallgitter hergestellt ist.
3. Brandschutzvorrichtung nach Anspruch 1, bei welcher das Flammensperrelement aus einem
Metallschaum hergestellt ist.
4. Brandschutzvorrichtung nach einem der Ansprüche 1 bis 3 mit wenigstens drei Schichten
(31, 32, 33; 41, 42, 43), wobei die getrennten Schichten abwechselnd unterschiedliche
Funktionen haben, d. h. eine Flammensperrfunktion oder eine Feuerwiderstandsfunktion.
5. Brandschutzvorrichtung nach Anspruch 4, bei welcher die Vorrichtung drei Schichten
hat, die aufeinanderfolgend eine Flammensperrfunktion, eine Feuerwiderstandsfunktion
und eine Flammensperrfunktion haben.
6. Brandschutzvorrichtung nach Anspruch 4, bei welcher die Vorrichtungen drei Schichten
hat, die aufeinanderfolgend eine Feuerwiderstandsfunktion, eine Flammensperrfunktion
und eine Feuerwiderstandsfunktion haben.
7. Lagerraum (2; 10), der wenigstens eine Wand (6; 11) mit wenigstens einer Gaskanalöffnung
(5; 12, 13) aufweist, wobei in wenigstens einer Gaskanalöffnung (5; 12, 13) eine Brandschutzvorrichtung
(23; 14) nach einem der vorhergehenden Ansprüche vorgesehen ist.
8. Lagerraum nach Anspruch 7, bei welchem das Flammensperrelement (16) zu der Innenseite
des Lagerraums hin und das Feuerwiderstandselement (15) zur Außenseite des Lagerraums
hin gerichtet ist.
9. Lagerraum nach Anspruch 7, beil welcher das Feuerwiderstandselement (15) zu der Innenseite
des Lagerraums hin und das Flammensperrelement (16) zur Außenseite des Lagerraums
hin gerichtet ist.
1. Dispositif anti-incendie (14), convenant pour être placé dans une ouverture de passage
de gaz (12 ; 13) dans une paroi (11), le dispositif présentant une condition de non-activation
dans laquelle le dispositif est perméable à un courant de gaz circulant à travers
ledit passage ; le dispositif comprenant un élément ignifuge (15) qui se présente
sous forme de grille définissant des ouvertures de circulation de gaz, la grille possédant
la propriété, en réponse à une augmentation de la température, de fermer lesdites
ouvertures de circulation de gaz, de telle sorte que ledit courant de gaz soit bloqué
dans une condition activée ; caractérisé par un élément arrête-flame (16), ledit élément
arrête-flame et ledit élément ignifuge (15) étant disposés en série par rapport audit
courant de gaz.
2. Dispositif anti-incendie suivant la revendication 1, dans lequel l'élément arréte-flame
(16) est réalisé en une toile métallique ou en une grille métallique.
3. Dispositif anti-incendie suivant la revendication 1, dans lequel l'élément arrête-flame
est réalisé en me mousse métallique.
4. Dispositif anti-incendie suivant l'une ou l'autre des revendications 1 à 3, comprenant
au moins trois couches (31, 32, 33 ; 41, 42, 43) dans lequel les différentes couches
ont alternativement des fonctions différentes, à savoir une fonction arrête-flame
ou une fonction ignifuge.
5. Dispositif anti-incendie suivant la revendication 4, dans lequel le dispositif présente
trois couches qui sont, successivement, arrête-flame, ignifuge et arrête-flame.
6. Dispositif anti-incendie suivant la revendication 4, dans lequel le dispositif présente
trois couches qui sont, successivement, ignifuge, arrête-flame, ignifuge.
7. Espace d'entrepossge (2 ; 10) présentant au moins une paroi (6 ; 11) avec ou moins
une ouverture de passage de gaz (5 ; 12, 13), dans lequel est prévu, donc ladite au
moins une ouverture de passage de gaz (5 ; 12, 13), un dispositif anti-incendie suivant
l'une ou l'autre des revendications précédentes.
8. Espace d'entreposage suivant la revendication 7, dans lequel l'élément arrête-flame
(16) est dirigé vers l'intérieur de l'espace d'entreposage et l'élément ignifuge (15)
est dirigé vers l'extérieur de l'espace d'entreposage.
9. Espace d'entreposage suivant la revendication 7, dans lequel l'élément ignifuge (15)
est dirigé vers l'intérieur de l'espace d'entreposage et l'élément arrête-flame (16)
est dirigé vers l'extérieur de l'espace d'entreposage.