(29 days)
The VERIFY Spore Test Strip for S40 Sterilant Concentrate is intended to provide users with a means to assess spore kill by S40 Sterilant use dilution in the STERIS automated Liquid Chemical Sterilant Processing Systems (SYSTEM 1E and SYSTEM 1® endo Liquid Chemical Sterilant Processing Systems and enspire 3000 Series Cleaning and Liquid Chemical Sterilant Processing System). A "no growth" result from the VERIFY Spore Test Strip for S40 Sterilant Concentrate after 24 hours of incubation indicates that the liquid chemical sterilization process achieved the conditions necessary to kill at least 1 x 105 viable spores (5 logs) on the spore test strip (STS). It does not confirm the expected full performance of the liquid chemical sterilization cycle.
The Spore Test Strip for S40 Sterilant Concentrate (STS) consists of a 1 % in. x 14 in. filter paper-based strip inoculated with Geobacillus stearothermophilus spores and is enclosed in a glassine envelope. The STS are provided with media vials containing a modified tryptic soy broth with phenol red pH indicator, and a transfer clip. The transfer clip is used to remove the STS from the glassine envelope and serves to hold the strip in a fixed location in either the enspire 3000 Series Cleaning and Liquid Chemical Sterilant Processing System (enspire CLCSPS) or the SYSTEM 1E or SYSTEM 1 endo Liquid Chemical Sterilant Processing system. After the cycle concludes, the transfer clip is used to aseptically transfer the STS from the processor into the growth media for incubation at 55-60°C for a minimum of 24 hours but may be incubated for up to 7 days. If the media remains red and non-turbid, the user interprets the results as a pass. If the media color turns yellow or is turbid, the user interprets the result as a fail. The shelf life is 12 months when stored at 2-24°C and 30-80% relative humidity (RH) away from sterilizing agents and excessive heat.
There are no changes to the strip itself for this submission; only an expansion to the exposure time to the chemical sterilant.
The provided document, an FDA 510(k) Premarket Notification summary for the "VERIFY SPORE TEST STRIP for S40 STERILANT CONCENTRATE," details the acceptance criteria and the study proving the device meets these criteria.
Here's the breakdown:
1. Table of Acceptance Criteria and the Reported Device Performance:
The primary acceptance criteria for this device revolve around demonstrating its continued performance as a spore test strip, specifically that the expansion of contact time with the liquid chemical sterilant does not negatively impact its ability to accurately assess spore kill.
| Test | Acceptance Criteria | Result |
|---|---|---|
| Population Wash Off Testing | The modification does not affect the performance of the device. | Pass |
| Bacteriostasis Testing | The modification does not affect the performance of the device. | Pass |
| Implied Performance Criteria (from Intended Use & Predicate Comparison): | ||
| Ability to indicate ≥ 5 logs kill of Geobacillus stearothermophilus spores | A "no growth" result from the VERIFY Spore Test Strip for S40 Sterilant Concentrate after 24 hours of incubation indicates that the liquid chemical sterilization process achieved the conditions necessary to kill at least 1 x 105 viable spores (5 logs) on the spore test strip (STS). | Demonstrated as substantially equivalent to predicate, which has this capability. |
| Shelf Life | 12 months | Identical to predicate. |
| Resistance Characteristics (at 1635 ppm PAA) | D-value 12 – 26 seconds; Survival Time ≥ 38 seconds; Kill Time ≥ 239 seconds | Identical to predicate. |
2. Sample Size Used for the Test Set and the Data Provenance:
The document does not explicitly state the numerical sample size for the "Population Wash Off Testing" and "Bacteriostasis Testing." It only indicates that these tests were performed and passed.
The data provenance is implied to be prospective testing conducted by the manufacturer, STERIS Corporation, in support of this 510(k) submission. The country of origin of the data is not specified, but given that STERIS Corporation is based in Mentor, Ohio, USA, it is highly probable the testing was conducted in the USA.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts:
This information is not provided in the document. The nature of these tests (Population Wash Off and Bacteriostasis Testing for a biological indicator) suggests laboratory-based assessments rather than expert interpretation of complex medical images, therefore, detailed information on expert consensus is not typically required or provided for this type of device.
4. Adjudication Method for the Test Set:
This information is not provided in the document. For the type of testing described (objective laboratory assays), an adjudication method like 2+1 or 3+1 for human readers is not applicable. The results are likely determined by predefined laboratory protocols and measurements.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:
No, an MRMC comparative effectiveness study was not done. This type of study is relevant for AI-assisted diagnostic tools where human readers interpret medical images. The device in question is a biological indicator for sterilization monitoring, not a diagnostic imaging device.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
Yes, in essence. The "Population Wash Off Testing" and "Bacteriostasis Testing" are standalone tests of the device's physical and biological integrity and performance characteristics, independent of human interpretation beyond reading the final culture results (growth/no growth). The device itself functions as a standalone indicator of sterilization efficacy.
7. The Type of Ground Truth Used:
The ground truth for the performance of this device is established by:
- Laboratory Testing: Directly measuring the
Population Wash Off(the number of viable spores remaining on the strip after specified processing) andBacteriostasis(the absence of inhibitory substances affecting subsequent bacterial growth). - Biological Efficacy: The ultimate ground truth for a spore test strip is its ability to accurately reflect the killing of the specified 5 logs of Geobacillus stearothermophilus spores, as confirmed by standard microbiological culture methods (absence of growth after incubation).
8. The Sample Size for the Training Set:
This information is not applicable and therefore not provided. This device is a biological indicator, not a machine learning or AI model that requires training data.
9. How the Ground Truth for the Training Set Was Established:
This information is not applicable. As stated above, this device does not involve a training set as it is not an AI/ML model.
§ 880.6887 Spore test strip.
(a)
Identification. The spore test strip consists of a carrier or strip with a known number of spores, at least 5 log10 per strip, of known resistance to a particular liquid chemical sterilant in a liquid chemical sterilant processing system. A “no growth” result from the spore test strip after the specified predetermined incubation period indicates that the liquid chemical sterilization process achieved the conditions necessary to kill the specified minimum number of viable spores on the test strip which is 5 log10 spores/strip; it does not confirm the expected full performance of the liquid chemical sterilant processing cycle because full performance is a 6 log10 spore kill in a full liquid chemical sterilization cycle.(b)
Classification. Class II (special controls). The special controls for this device are:(1)
Spore strip characterization. (i) Population of viable spores on strip shall be a minimum of 5 log10 after physical wash off of spores from the strip by exposure to liquid chemical sterilant in the liquid chemical sterilant processing system, which should be validated over the claimed shelf life.(ii) The resistance characteristics of the viable spores on the strip should be defined and be validated over the claimed shelf life.
(iii) The spore strip description should address the carrier material, how the spores are placed on the carrier, and whether there is any feature that minimizes spore wash off. Bacteriostasis of the spore strip materials should be evaluated.
(iv) Incubation time for viable spores on the strip should be validated under the specified incubation conditions over the claimed shelf life.
(2)
Simulated Use Testing. Simulated use testing should demonstrate performance of spore test strip in liquid chemical sterilant/high level disinfectant under worst case in use conditions over the claimed shelf life.(3)
Labeling. Labeling should specify appropriate instructions, warnings, cautions, limitations, and information relating to viable spore population, resistance characteristics, and interpretation of a “no growth” result.