Tapered indicator to be used in process challenge devices

Abstract

Indicator (22) for process challenge devices (PCDs) to monitor sterilizing processes, comprising a plurality of indicator areas (50, 54, 58, 62, 66) which react with a sterilizing agent and which are arranged spaced apart on a common carrier element (18) in a longitudinal direction (70) of said carrier element (18), whereby said carrier element (18) is built tapered along its longitudinal direction (70).

Claims

1. Indicator (22) for process challenge devices (PCDs) to monitor sterilizing processes, comprising a plurality of indicator areas (50, 54, 58, 62, 66) which react with a sterilizing agent and which are arranged spaced apart on a common carrier element (18) in a longitudinal direction (70) of said carrier element (18), characterized in that said carrier element (18) is built tapered along its longitudinal direction (70).

2. Indicator (22) according to claim 1, whereby said carrier element (18) is built flat and whereby said tapering realizes a reduction of the width of said carrier element (18) along said longitudinal direction (70).

3. Indicator (22) according to claim 1 or 2, whereby said carrier element (18) tapers in a continuous way.

4. Indicator (22) according to one of the previous claims, comprising between 2 and 7, especially 5, indicator areas (50, 54, 58, 62, 66).

5. Indicator (22) according to on the previous claims, with a length between 40 mm and 70 mm, especially 50 mm and/or with a maximal width between 4 mm and 8 mm.

6. Indicator (22) according to one of the previous claims, which is built as a chemical and/or biological and/or physical indicator.

7. Indicator (22) according to one of the previous claims, whereby said carrier element (18) is made of any material, preferably of paper, plastic foil or any metal in flat shape of any thickness, preferably 0.5-1 mm thick or of any other shape.

8. Indicator (22) to one of the previous claims, whereby the chemical or physical indicator (22) can be detected by daylight and/or UV-light and/or infrared and/or X-rays and/or y rays with a corresponding detection unit.

9. Indicator sheet (2), on which a plurality of strips (4-14) is arranged, characterized in cut lines arranged on said sheet (2) such that a division of said sheet (2) along said cuts results in a plurality of indicators (22) according to one of the previous claims.

10. Sheet (2) according to claim 9, whereby said cut lines are replaced by perforated lines along which said sheet (2) can be separated and taken out.

11. Sheet (2) according to claim 9 or 10, whereby between 15 and 30, especially 25, indicators can be separately taken out from said sheet (2).

12. Process challenge device (130), comprising a detector chamber (80) with an indicator volume (86) configured to receive an indicator (22) according to one of the previous claims, characterized in that said indicator volume (86) tapers in a longitudinal direction as to fit said indicator (22).

13. Process challenge device (130) according to claim 12, whereby said detector chamber (80) comprises a dead end (84), and whereby said indicator volume (86) tapers in such a way that its wide end is located at said dead end (84), especially which depends on the PCD constructions.

14. Process challenge device (130) according to claim 12 or 13, comprising two parts (100, 102), namely a housing part (100) and an insertion part (102), whereby said insertion part (102) is at least partially insertable into said housing part (100) in such a way that said detector chamber (80) is arranged without any seal inside said both parts (100, 102).

15. Process Challenge Device (130) according to one of the claims 12 to 14, designed as a tube with a capsule at one end contains a tapered indicator holder according to claims 1 to 8.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Further features and advantages of the present invention shall become clearer from the following detailed description of some of its preferred embodiments, made with reference to the attached schematic drawings and given as an indication and not for limiting purposes.

[0037] In particular, the attached drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification. The drawings together with the description explain the principles of the invention. In the drawings, corresponding characteristics and/or components are identified by the same reference numbers. In these drawings:

[0038] FIG. 1 shows an indicator sheet in a preferred embodiment with a plurality of strips;

[0039] FIG. 2 shows the sheet according to FIG. 1 in a different representation;

[0040] FIG. 3 shows an indicator in a preferred embodiment;

[0041] FIG. 4 shows a detector chamber of a process challenge device with an inserted indicator according to FIG. 3; and

[0042] FIG. 5 shows a process challenge device in a preferred embodiment.

DETAILED DESCRIPTION

[0043] In FIG. 1, an indicator sheet 2 is shown which comprises a support element 18a on which several strips 4, 6, 8, 10, 12 of sensitive indicator colors are arranged. The sheet 2 and therefore also the support element 18a has a rectangular shape. Preferably, the strips 4-12 have, respectively, a rectangular shape and extend over the whole width w of the support element 18a. The strips 4-12 are arranged distanced in the direction of height h of the support element 18a. In the preferred embodiment shown, five strips 4-12 are arranged on the support element 18a.

[0044] In FIG. 2, the sheet 2 is shown in a different view/representation. On this sheet 2, cuts are arranged which currently comprise lines of which, as an example, lines 32, 34, 36, 38 are labelled. The cuts alternatively are perforations along the respective lines 32-38. The perforations extend along the whole height h of sheet 2 between two borders 22, 24 of sheet 2. When the sheet 2 is divided along perforated line 32 by separating adjacent parts, one indicator 22 (see FIG. 3) is taken off from the sheet 2 and can immediately be used. When sheet 2 is further divided along perforated line 34, a further indicator 24 is taken off. In this way, in the preferred embodiment shown, 25 indicators 22 can be taken off from one sheet 22. The advantage of providing an indicator sheet 2 in this way allows a convenient cutting/perforation/packaging of indicators.

[0045] Two adjacent perforated lines, for example lines 34 and 34, are, respectively, inclined towards each other, i.e. they do not run parallel. When the sheet 2 is divided along these adjacent lines, an indicator 22 is taken off which is in longitudinal direction alternating wide and narrow.

[0046] An indicator 22 which is taken off from sheet 2 in a preferred embodiment is shown in FIG. 3. The indicator 22 comprises a carrier element 18 which is a part of the support element 18a of indicator sheet 2 which has been separated from the remaining sheet 2. On carrier element 18, several sensitive or indicator areas 50, 54, 58, 62, 66 are arranged which react in response to the presence of a sterilizing agent. These indicator areas 50-66 are, respectively, parts of the strips 4-12 of sheet 2. Between sensitive areas 50-66, regions 56, 60, 64 of the support element 18a are arranged by which the indicator areas 50-66 are spaced apart from each other.

[0047] As can be seen in FIG. 3, the width of the indicator 22, i.e. its extension in a lateral direction 74, decreases along longitudinal direction 70. In the preferred embodiment shown, the width decreases continuously, especially conically in two dimensions. In this way, at a first end 90 the indicator 22 has a larger width than at second end 92. The indicator 22 is therefore asymmetrically built and the first end 90 is easily distinguishable from the second end 92.

[0048] The indicator 22 is preferably a chemical indicator, whereby the carrier element 18 of the indicator 22 is made from paper, metal, glass fiber, plastic, stainless steel, any plastic foil, Tyvek or any combination. Alternatively, it is a biological indicator strip, whereby the carrier element 18 of the spores is made of paper, metals, glass, glass fiber, plastic or any combination of these materials. The indicator 22 can be surface-protected or covered on both sides with different chemical indicator colors to be used to monitor different sterilization processes.

[0049] In FIG. 4, a detector chamber 80 of a PCD 130 shown in FIG. 5 is shown which comprises an indicator volume 86. The detector chamber or holder 80 comprises a dead end 84 which is a dead end for a gas passage. The indicator volume 86 is dimensioned to fit the indicator 22 only in one orientation, i.e. the narrow end 92 of indicator 22 is located at the dead or closed end 84.

[0050] FIG. 5 shows a process challenge device (PCD) 130 in a preferred embodiment. The PCD 130 in a preferred embodiment comprises a first part 100 or housing part and a second part 102 or insertion part, whereby the second part 102 is insertable into the first part 100. The detector holder 80 shown in FIG. 4 is insertable into second part 102. Then second part 102 which comprises a head part 104 is inserted into first part 100 until an edge 122 of second part 102 is in contact with an edge 124 of first part 100.

[0051] The housing and/or said insertion parts are preferably made of metal, plastic or metal-plastic-bonded system.

[0052] The head part 104 allows a convenient handling of parts 100, 102, especially insertion and removal of second part 102 into first part 100. After the sterilizing process has finished, the second part 102 is pulled out of first part 100 and the detector chamber 80 is extracted. Since the indicator has an asymmetric shape, especially a conical design, also after extraction of the indicator from the detector chamber 80, it can be reliably determined if the sterilizing agent has reached the dead end of the detector chamber 80 which corresponds to the location of the indicator which is most difficult to reach by the sterilizing agent. In this way, a very accurate assessment of the quality and accuracy of the sterilizing process can be made.

[0053] Preferably the two parts 100, 192 fit into each other without sealing and form, combined together, in series connected volumes for providing specific penetration characteristics for sterilization agents. Advantageously, the series of volumes provides connected channels, whereby one end of these channels is connectable to a sterilization chamber and the other end is connected to the detector chamber which is configured to house, alternatively one or more chemical, biological, or physical indicators 22 for detecting the presence of a sterilizing agent.