Test chamber, use and method for the microbial and/or particulate barrier testing of a product

Abstract

A test chamber for the microbial and/or a particulate barrier testing of a number of products, the test chamber having a test space which has, at least along a straight section, an inner extent of at least 1.5 m. As a result, a particularly homogeneous microbe and/or particle distribution is achieved. The invention also relates to an associated use and to an associated method.

Claims

1.-15. (canceled)

16. Test chamber for the microbial and/or particulate barrier testing of a number of products, the test chamber comprised of: a test space for the products, the test space being accessible by way of an opening; a closing element, by means of which the opening can be closed; a microbe and/or particle introducing device for introducing microbes and/or particles into the test space; a plurality of pressure changing elements, which are designed to change an air pressure in the test space; and the test space being designed to be pressure-tight within a pressure range when the opening is closed by the closing element; characterized in that the test space has, at least along a straight section, an inner extent of at least 1.5 m.

17. The test chamber of claim 16, characterized in that the test space has a width of at least 1.5 m or 1.8 m and/or the test space has a height of at least 1.5 m or 2 m or 2.2 m, and/or the test space has a depth of at least 1.5 m or 2 m or 2.7 m.

18. The test chamber of claim, 16, characterized in that the test space has a volume of at least 3 m.sup.3, 5 m.sup.3, 8 m.sup.3, 10 m.sup.3 or 12 m.sup.3.

19. The test chamber of claim 16, characterized in that the test chamber has a plurality of placement surfaces arranged one above the other for the products in the test space.

20. The test chamber of claim 16, characterized in that the pressure range has a lower limit which lies at atmospheric pressure or lies 50 mbar, 100 mbar, 150 mbar, 200 mbar, 480 mbar or 500 mbar below atmospheric pressure.

21. The test chamber of claim 16, characterized in that the pressure range has an upper limit which lies at atmospheric pressure or lies 50 mbar, 100 mbar, 150 mbar, 200 mbar, 480 mbar or 500 mbar above atmospheric pressure.

22. The test chamber of claim 16, characterized in that the pressure changing elements are designed to set any pressure in the pressure range when the opening is closed.

23. The test chamber of claim 16, characterized in that a respective pressure changing element has a bellows, which is arranged in the test space and the volume of which is variable.

24. The test chamber of claim 23, characterized in that the test chamber has an air supply and/or air removal system, in order to change volumes of the bellows.

25. The test chamber of claim, 23, characterized in that the test chamber has a plurality of fans and/or a plurality of valves, in order to change volumes of the bellows.

26. The test chamber of claim 16, characterized in that the closing element is configured as a pivotable door.

27. The test chamber of claim 16, characterized in that the microbe and/or particle introducing device is configured as an aerosol generator.

28. The test chamber of claim 16, characterized in that the test chamber also has a plurality of microbe and/or particle collecting elements and/or microbe and/or particle detecting elements, in particular on-line microbe and/or on-line particle detecting elements, arranged in the test space.

29. A test chamber of claim 16, for use in the microbial and/or particulate barrier testing of a number of products.

30. A method for the microbial and/or particulate barrier testing of at least one product, the method comprising the following steps: introducing the product into a test space of a test chamber according to claim 16, closing the test space by means of the closing element, introducing microbes and/or particles into the test space by means of the microbe and/or particle introducing device, and changing the pressure in the test space according to a predetermined program.

Description

[0091] A person skilled in the art can take further features and advantages from the exemplary embodiment described below with reference to the accompanying figure and from the description then following of a sequence given by way of example of a microbial contamination testing by means of a test chamber according to the invention. In the drawing:

[0092] FIG. 1 shows a test chamber.

[0093] FIG. 1 shows a test chamber 100 according to an exemplary embodiment of the invention.

[0094] The test chamber 100 has a test space 105, which is accessible by way of an opening 107.

[0095] The opening 107 can be closed by means of a closing element in the form of a door 110. The door 110 is in this case pivotably secured, so that it can be opened and closed.

[0096] Arranged in the test space 105 in the present case are two shelves, which are secured on a side wall and form placement surfaces 120, 125. Stored on each of them in the present case is a product 5, 6, the products 5, 6 being intended for testing by means of a microbial and/or particulate barrier test. The products 5, 6 are in this case only schematically represented, so that it should be understood that virtually any products may be placed onto the placement surfaces 120, 125 in order to test them correspondingly.

[0097] Also, in the test space is a table 127. Stored on it is a further product 7, which is to be tested for microbial barrier properties.

[0098] When the door 110 closes the opening 107, the test space 105 is sealed in a pressure-tight and germ-proof manner. This applies at least within a predetermined pressure range, which extends from several hundreds of millibars below atmospheric pressure to several hundreds of millibars above atmospheric pressure.

[0099] Arranged in the test space 105 is an aerosol generator 130, which represents a microbe and/or particle introducing device. The aerosol generator 130 is designed to emit in the test space 105 aerosol 135, which contains microbes and/or particles.

[0100] These microbes and/or particles distribute themselves within the test space 105, so that the products 5, 6, 7 can be tested for barrier properties with respect to these microbes and/or particles. If it is found after completion of the test that corresponding microbes and/or particles have penetrated through sterile packagings of the products 5, 6, 7, the packagings clearly do not have the reliability that is required of them.

[0101] In order to simulate a change in pressure in the test space 105 during a test, there are altogether three pressure changing elements 140 located therein. Each pressure changing element 140 has a respective bellows 150. This can be externally inflated and reduced in size again. As a result, the pressure inside the test space 105 can be changed, without air having to be introduced from outside or having to be let out of the test space 105. This makes it possible to realize a change in pressure without influencing the microbe and/or particle concentration and without extracting microbes and/or particles.

[0102] For actuating the bellows 150, the test chamber 100 has a schematically represented air supply and/or air removal system 160. This is connected to the respective bellows 150 by means of a respective valve 170. The air supply and/or air removal system 160 has a fan 180, which can generate a pressure. This pressure can be selectively directed into the respective bellows 150 by way of the valves 170. As a result, a pressure in the respective bellows 150, consequently also in the test space 105, can be increased.

[0103] If the fan 180 is switched off and nevertheless a respective valve 170 is opened, the pressure in the respective bellows 150 is reduced. In this way, the pressure in the test space 105 can be both increased and reduced, so that it is possible to simulate a transporting situation for the products 5, 6, which in reality comprises for example transport by means of a truck and/or by means of an elevator, and consequently the passing through of areas with different air pressures.

[0104] For separately collecting the microbes contained in the aerosol 135, in the test space 105 there are three schematically represented petri dishes 8. These are coated with a nutrient medium, so that microbes that have entered can be collected and cultivated after carrying out the test. Each microbe in this case forms a colony, which is countable, in particular optically countable. The detection of the microbes is performed by means of a microbe detecting element 9, which is preferably designed as an on-line microbe monitoring element. As a result, it can with particular advantage already be tested during the test whether a desired number of microbes was contained in the air in the test space 105. For counting the microbe colonies, the microbe detecting element 9 may have a real-time laser-induced fluorescence system. On account of the size of the test chamber 100, it can be entered on foot.

[0105] This makes it easier for components to be taken in and out. To increase safety for operating personnel, the test chamber 100 has a detection system (not represented), which would detect a person located in the test space 105. It can in this way be ensured that a test that involves releasing microbe-containing aerosol 135 does not take place if there is a person in the test space 105.

[0106] The test space 105 has in the present case a width of 1.8 m, a height of 2.2 m and a depth of 2.7 m. Such dimensions have proven to be advantageous for typical applications. In particular, all of the dimensions mentioned are greater than 1.5 m and are consequently within a range in which a particularly homogeneous microbe and/or particle distribution has been observed. The reason for this is in particular that with such dimensions deposits on the walls are no longer as significant as in the case of small dimensions.

EXAMPLE SECTION

Sequence Given by Way of Example for Microbial Contamination Testing by Means of a Test Chamber According to the Invention:

[0107] First, a microbe-containing aerosol was sprayed into the test space by means of a microbe introducing device configured as an aerosol generator, so that subsequently there was a microbe suspension in all of the tubes of the aerosol generator. At the same time, the sprayed aerosol was extracted by way of a cleanroom module. After that, the test space was loaded with sterile product packagings to be tested for microbial barrier properties. For this purpose, the sterile product packagings were placed onto a table located in the test chamber.

[0108] Then it was checked by means of a detection system that there were no persons in the test chamber. After that, the door of the test chamber was closed. Next, the test was started. For this purpose, an air-admitting valve of the test space was closed. During the testing operation, a measurement by means of an on-line microbe monitoring device and a purification of the interior space of the test chamber by means of a cleanroom module took place. A microbe-containing suspension was sprayed by means of the aerosol generator over a time period of 1 minute. During the testing operation, pressure changes were carried out, for example at a maximum pressure changing rate of 1.1 mbar per second. During the pressure changes, there was no spraying of microbe-containing suspension. For carrying out the pressure changes, pressure changing elements configured as bellows were inflated by means of compressed air. A suction removal of the compressed air from the bellows was carried out by means of a vacuum pump.

[0109] After that, a microbe-containing suspension was once again sprayed over a time period of 1 minute. Then, pressure changes were once again carried out, spraying of the microbe-containing suspension not taking place during the pressure changes.

[0110] This was then followed by a rest phase for preventing air vortices. After that, a microbe-containing suspension was sprayed into the test space once again over a time period of 1 minute. Then, pressure changes were once again carried out, spraying of the microbe-containing suspension not taking place during the pressure changes.

[0111] Finally, the microbial contamination in the test chamber was reduced by way of the cleanroom module. After that, an air-admitting valve of the test chamber was opened, the microbes being kept back by means of a filter in the contamination space.

[0112] Then, the door of the test chamber was opened, and the test pieces were removed. Lastly, a disinfection (manual or automated, with a disinfecting liquid) of the test chamber was performed.

[0113] Advantages of the present invention are to be summarized (once again) as follows:

[0114] The dimensions of the test chamber according to the invention can correspond with particular advantage to actual keeping rooms and/or store rooms, it being possible for actual keeping and/or storing conditions, such as are to be encountered for example at transport companies, hospitals and medical practices, to be simulated. This also applies in particular to the relative size of products to be tested for microbial and/or particulate barrier properties and the test chamber according to the invention.

[0115] Furthermore, in the case of the test chamber according to the invention, a detection of the microbe and/or particle contamination conditions in the test space during an entire testing operation is possible with particular advantage.

[0116] Furthermore, in the case of the test chamber, an on-line detection of the microbe and/or particle contamination can be carried out during the entire testing.

[0117] Furthermore, for example a microbe- and/or particle-containing aerosol can be introduced into the test space a number of times or else the whole time during the testing. As a result, in particular a pre-defined number of microbes and/or particles can be obtained.

[0118] Furthermore, the pressure changing elements of the test chamber can be actively increased and/or reduced in size by way of an open-loop and/or closed-loop control.

[0119] A further advantage is that a plurality of products can be tested simultaneously, i.e. during one testing operation, together and in particular at the same height, for example on one placement surface of a rack, or at different heights, for example on different placement surfaces of a rack.

[0120] Furthermore, contamination of the surroundings of the test chamber with microbes and/or particles can be avoided, for example by means of a filter present in the test space.

[0121] Furthermore, the testing sequence, in particular the carrying out of pressure changes and/or the admission of a microbe- and/or particle-containing aerosol and/or a filtration of the test space air, can be automatically controlled and in particular tracked on-line.

[0122] Furthermore, constant initial conditions can be produced in the test space, for example by means of a cleanroom module located in the test space.

[0123] Furthermore, an initial microbe and/or particle contamination can be tested and detected, for example by means of an on-line microbe and/or particle monitoring device.

[0124] Furthermore, sterile test conditions can be created, in particular by means of a cleanroom module arranged in the test chamber.

[0125] Furthermore, microbes and/or particles can be kept in suspension, for example by producing an active and/or thermal air flow.

[0126] Furthermore, a homogeneous or directed microbe- and/or particle-contaminated flow can be produced within the test chamber by producing air flows, for example by means of fans.

[0127] Furthermore, a partial microbe and/or particle isolation can be produced by a static charging of surfaces.

[0128] Furthermore, the products to be tested for microbe and/or particle barrier properties can be rearranged during the testing operation by means of a robot arranged in the test chamber, and thus the actual handling of products, for example in hospitals or medical practices, can be simulated.

[0129] Furthermore, a disinfection (so-called dry disinfection) of the test chamber can be carried out for example by way of UV radiation. As a result, a rapid restoration of initial conditions suitable for carrying out a new test cycle is possible with particular advantage. Alternatively, a manual or automated disinfection with a disinfecting liquid is also possible.