(295 days)
The NOSOGARD line of filters are intended to operate on EPA quality drinking water sources as a microbial retention filter. NOSOGARD filters are available in models suitable for the control of bacteria equal to or greater in size than Brevundimons diminuta and models for microbial removal equal to or greater than Legionella pneumophila. The NOSOGARD is suitable for general point of use infection control for procedures such as cleaning, rinsing of equipment, hand washing and bathing where the reduction of such microorganisms in the water is desired.
The Nosogard is not intended for use in the production of USP sterile water for use in infusion, injection of fluids for use in dialysis treatments.
Nosogard Filters are disposable Polyethersulfone (PES) membrane filters sealed in a polypropylene housing designed to be installed by facility personnel at point of use locations where the control of bacteria in the drinking water supply is desired for device cleaning, handwashing and bathing applications. These filters are designed to be installed as attachments to faucets or as a handheld shower head.
The Evoqua Water Technologies Nosogard Filters are intended as microbial retention filters for EPA quality drinking water sources, for general point-of-use infection control in procedures like cleaning, rinsing equipment, hand washing, and bathing. They are not intended for producing USP sterile water for infusion, injection, or dialysis treatments.
Here's an analysis of the acceptance criteria and study proving the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are generally focused on bacterial retention (no grow-through), flow rate, structural integrity (housing burst pressure, pulse testing, drop testing), and shelf-life, along with biocompatibility and sterilization efficacy.
| Acceptance Criteria / Performance Claim | Reported Device Performance (Nosogard Filters) |
|---|---|
| Bacterial Retention (Brevundimonas diminuta) | |
| No grow through ≤7 days when challenged with >10^7 cfu/cm² Brevundimonas diminuta | Passed (Nosogard 7/31 Filter) |
| No grow through ≤31 days when challenged with >10^7 cfu/cm² Brevundimonas diminuta | Passed (Nosogard 31 Day Filter, Nosogard 31 Day Shower Wand) |
| No grow through ≤62 days when challenged with >10^7 cfu/cm² Brevundimonas diminuta | Passed (Nosogard 62 Day Filter, Nosogard 62 Day Shower Wand) |
| Bacterial Retention (Legionella pneumophila) | |
| No grow through ≤31 days when challenged with >10^7 cfu/cm² Legionella pneumophila | Passed (Nosogard 7/31 Filter, Nosogard 31 Day Shower Wand) |
| No grow through ≤62 days when challenged with >10^7 cfu/cm² Legionella pneumophila | Passed (Nosogard 62 Day Filter, Nosogard 62 Day Shower Wand) |
| Flow Rate | |
| 1.25" Nosogard 7/31 Filter: 0.22 ft³/min at 44psi inlet pressure | Passed |
| 2.5" Nosogard 7/31 Filter: 0.40 ft³/min at 29psi inlet pressure | Passed |
| Nosogard 31 Day Filter: 0.19 ft³/min at 44psi inlet pressure | Passed |
| Nosogard 62 Day Filter: 0.25 ft³/min at 44psi inlet pressure | Passed |
| Nosogard 31 Day Shower Wand: 0.79 ft³/min at 44psi inlet pressure | Passed |
| Nosogard 62 Day Shower Wand: 0.39 ft³/min at 44psi inlet pressure | Passed |
| Housing Burst Pressure | |
| 10 Barg at 40°C | Passed (All models explicitly mentioned) |
| Pulse Testing / Integrity after Cycles | |
| Nosogard 7/31 Filter: Integral post 2000 cycles x 5 mins x 0-6.2 Barg pulses at 66°C | Passed |
| Nosogard 31 Day Filter: Integral post 2000 cycles x 5 mins x 0-6.2 Barg pulses at 66°C | Passed |
| Nosogard 31 Day Shower Wand: Integral post 124 cycles x 7 mins x 0-5 Barg pulses at 40°C | Passed |
| Nosogard 62 Day Shower Wand: Integral post 248 cycles x 7 mins x 0-5 Barg pulses at 40°C | Passed |
| Shelf Life | |
| Packaging forms a sterile barrier for at least 3 years | Passed (All models implicitly covered, explicitly stated for all listed models not described above) |
| Biocompatibility | |
| Meets requirements in FDA memorandum #G95-1 | Passed (All models implicitly covered, explicitly stated for all listed models not described above), including USP Class VI, USP Biological Reactivity Tests, In Vitro, ISO 10993 Part 5 (cytotoxicity), Part 10 (irritation and skin sensitization). |
| Sterilization | Adequate dosage and exposure utilized to assure a sterile product prior to release (tested post gamma irradiation in accordance with ANSI/AAMI/ISO 11137-2:2012). |
| Integrity after Drop Test | Retains integrity at stated maximum operating pressure and temperatures after being subjected to a 6-foot unprotected drop. Integrity verified with membrane diffusional flow testing. |
| Integrity after Simulated Use/Cycle Testing | Successfully retains integrity after exposure to repeated pressurization, flow, and depressurization cycles at maximum stated temperatures and pressure. Integrity verified with diffusional flow testing. |
2. Sample Size Used for the Test Set and the Data Provenance
The document does not explicitly state the exact sample size for each test. However, it indicates that "All filter designs were placed in test assemblies and operated continuously for a period at least equal to the useful life of the model with repetitive inoculations of the subject microbe." This implies that a sufficient number of units representing each filter design were tested.
- Sample Size: Not explicitly quantified with a specific number for each test across all models. It implies a representative sample of "all filter designs."
- Data Provenance: The studies are described as "Non-Clinical Performance Testing" and "Bench Testing," which are laboratory-based studies conducted by the manufacturer (Evoqua Water Technologies, LLC.) to evaluate device performance against established standards. The data is retrospective in the sense that the results are being reported after the tests were conducted for the 510(k) submission. There is no mention of country of origin for the data, but it is submitted to the FDA 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 applicable to this type of device. The ground truth for device performance, such as bacterial retention or physical integrity, is established through standardized laboratory testing methods (e.g., ASTM F838 for bacterial retention, pressure tests). These tests rely on objective measurements and established scientific protocols rather than expert consensus on interpretation of, for example, medical images.
4. Adjudication Method for the Test Set
This information is not applicable. Adjudication methods like "2+1" or "3+1" are typically used in clinical studies involving interpretation of data by multiple human experts (e.g., radiologists interpreting images) to establish a consensus ground truth. For the laboratory-based performance testing of a water filter, the results are derived from objective measurements per defined testing protocols.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
This information is not applicable. MRMC studies are used to evaluate AI systems that assist human readers in tasks like medical image interpretation. The Nosogard Filter is a physical water filtration device, not an AI-powered diagnostic tool. Therefore, human reader performance or AI assistance effects are irrelevant to its evaluation.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
This information is not applicable. The Nosogard Filter is a physical device, not an algorithm or AI system.
7. The Type of Ground Truth Used
The ground truth for the performance evaluation of the Nosogard Filters is based on objective, quantifiable measurements derived from standardized laboratory bench testing.
- Bacterial Reduction: Measured according to ASTM F838 Standard Test Method for Determining Bacterial Retention of Membrane Filters Utilized for Liquid Filtration, using specific bacterial challenges (Brevundimonas diminuta, Legionella pneumophila) at defined concentrations. The "ground truth" is the quantitative reduction in colony-forming units (cfu) to demonstrate "no grow through" or a >10^7 reduction.
- Physical Integrity (Flow Rate, Burst Pressure, Pulse Testing, Drop Testing): The ground truth is adherence to specified physical parameters (e.g., specific flow rates, resisting a certain pressure, maintaining integrity after cycles/drops) as verified by direct measurement and observation under controlled conditions.
- Biocompatibility: Adherence to established standards (e.g., USP Class VI, ISO 10993) which define acceptable biological responses.
- Sterilization: Demonstrated efficacy according to ANSI/AAMI/ISO 11137-2:2012.
- Shelf Life: Demonstrated sterile barrier integrity for a specified period (3 years) based on ISO 11607:2009.
8. The Sample Size for the Training Set
This information is not applicable. The Nosogard Filter is not an AI or machine learning device that requires a "training set" for model development. Its performance is based on its physical design and material properties.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable for the same reason as point 8.
§ 876.5665 Water purification system for hemodialysis.
(a)
Identification. A water purification system for hemodialysis is a device that is intended for use with a hemodialysis system and that is intended to remove organic and inorganic substances and microbial contaminants from water used to dilute dialysate concentrate to form dialysate. This generic type of device may include a water softener, sediment filter, carbon filter, and water distillation system.(b)
Classification. Class II (special controls). The device, when it is a water purification subsystem disinfectant, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 876.9.