The Gambro Central Water Treatment System CWP 100 – WRO H is designed to produce water of adquate quality for hemodialysis, both chemically and microbiologically with an adequate flow, provided that the feed water complies with the existing standards for drinking water and has been properly pre-treated.

Device Description

The Gambro Central Water Treatment System CWP 100 - WRO H is designed to produce water of adquate quality for hemodialysis, both chemically and microbiologically with an adequate flow, provided that the feed water complies with the existing standards for drinking water and has been properly pre-treated. The WRO or the base unit of the CWP system, operates under the principle of reverse osmosis (RO) which is the preferred method for the purificationof water for hemodialysis. This system removes at least 95% of the total dissolved salts (based on conductivity measurements) and more than 99% of the bacteria and endotoxins from the inlet water. The WRO H also include a heat disinfection unit for disinfection of the distribution system which utilizes hot water to minimize any form of microbial growth and biofilf formation. With this system, dialysis machines can be included in this heat disinfection cycle, provided that they have heat disinfection capability. This procedure is called integrated heat disinfection.

In order to ensure that the microbiological quality will be maintained, this system has:

an automated disinfection procedure to keep the membrane surfaces clean and to . minimize bacterial growth;
a hygenic design with smooth surfaces and a minimum of stagnant zones; .
automatic flushing programs at preset intervals when the system is not in use ●

In addition, the WRO H has been designed to reduce water consumption by automatically regulating the pump speed to the actual demand of pure water.

After pretreatment (i.e. sediment filter, water softener, charcoal filter, etc.) the water enters an inlet tank (please refer to position 4 on the following diagram) via a solenoid valve (1). The inlet water tank (4) has a float valve (5) and an air gap to help isolate the flowpath from the municipal water system. The main pump (33) then creates a pressure of up to 20 bar that is required for the reverse osmosis process.

Pure water from the WRO unit is distributed directly to the distribution system in the hemodialysis unit via solenoid valves (48), (103), and (105). Excess pure water that has not been used in the hemodialysis unit is recirculated back to the inlet water tank (4) via solenoid valve (106).

In order to reduce water consumption, the speed of the pump is automatically adjusted so that the return flow of water is kept constant. Part of the reject water is recirculated back to the sucking side of the main pump via valve (71) to help minimize water consumption and to maintain a high flow velocity over the membrane surface. The rest of the reject water is, however, continuously sent to the drain via a needle valve (41).

The WRO unit utilizes a proportioning pump (45) and solution container (46) to proportion disinfectant during the disinfection cycle. The proportioning pump is disconnected from the flow path during normal operation.

The pure water line has a solenoid valve (36) for automatic flushing to drain at the start up, in conductivity alarm situations, every two hours, when the unit is in stand-by mode and at rinse during disinfection. The pure water line also has a solenoid valve arrangement to isolate the system from the distribution system during disinfection. The WRO unit has an overflow valve (64) on the pure water side to control pressure and to relieve pressure peaks.

AI/ML Overview

The provided document describes the Gambro Central Water Treatment System CWP 100 – WRO H, a water purification system for hemodialysis. This device was cleared through the 510(k) pathway, which focuses on demonstrating substantial equivalence to a legally marketed predicate device rather than de novo clinical efficacy studies. Therefore, the document does not contain typical clinical study data with acceptance criteria based on patient outcomes or expert reviews. Instead, the "acceptance criteria" are implied by the performance characteristics demonstrated to establish substantial equivalence.

Here's an analysis of the available information regarding acceptance criteria and supporting studies:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Implied by Predicate/Intended Use)	Reported Device Performance
Chemical Purity: Produce water of adequate chemical quality for hemodialysis.	Removes at least 95% of total dissolved salts (based on conductivity measurements). In vitro performance testing confirmed normal operating performance for rejection of dissolved salts.
Microbiological Purity: Produce water of adequate microbiological quality for hemodialysis.	Removes more than 99% of bacteria and endotoxins from inlet water. The system has automated disinfection, hygienic design, and automatic flushing programs to maintain microbiological quality. The WRO H also includes a heat disinfection unit (60°C or 90°C) for the distribution system, capable of maintaining 85°C in a 150m piping system. In vitro performance testing confirmed normal operating performance for rejection of bacteria and pyrogen (endotoxins).
Adequate Flow: Provide an adequate flow of purified water.	In vitro performance testing was performed to establish normal operating performance to include flow rates. The system automatically regulates pump speed to actual demand. The heat disinfection unit ensures continuous circulation of hot water.
Safety: Materials having water contact are safe.	Additional testing was performed to evaluate the safety of the materials having water contact at various temperatures. The device utilizes substantially equivalent water contact materials (pumps, tubing, fittings) as the predicate device.
Performance vs. Predicate: Performs as well as the predicate device.	The manufacturer concluded that the device is safe, effective, and performs as well as the predicate device based on in vitro performance testing. The device is substantially equivalent to the Osmonics Osmo 23 G Series Reverse Osmosis Machines.

2. Sample Size Used for the Test Set and Data Provenance

The document does not specify a "test set" in the traditional sense of a clinical study with a defined sample size of patients or images. The testing was primarily in vitro performance testing on the device itself.

Sample Size: Not applicable in terms of "test set" for clinical data. The testing involved multiple runs or configurations of the Gambro Central Water Treatment System.
Data Provenance: The studies were non-clinical (in vitro performance testing) conducted by Gambro Healthcare. The location of these tests or the specific country of origin for the "data" is not explicitly stated beyond Gambro Healthcare's location in Lakewood, CO. The testing is retrospective, in the sense that it was completed prior to the 510(k) submission.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications

Not applicable. This was a non-clinical performance study on a water treatment system, not a diagnostic or clinical decision-making device. Ground truth in this context would be established by validated analytical methods (e.g., chemical assays, microbiological cultures, flow measurements) rather than expert consensus.

4. Adjudication Method for the Test Set

Not applicable. As described above, there was no "test set" requiring expert adjudication. Performance was measured objectively using instrumentation and analytical methods.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No. An MRMC study is relevant for diagnostic devices where human readers interpret medical images or data. This device is a water treatment system, not a diagnostic tool.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

Yes, implicitly. The "in vitro performance testing" described is essentially a standalone evaluation of the device's capabilities without human intervention influencing its core function (i.e., water purification). The device's automated features (disinfection, flushing, pump regulation) operate independently. While an operator initiates the heat disinfection cycle, the performance data (e.g., % salt rejection, % bacteria removal, flow rates) represents the machine's intrinsic capabilities.

7. Type of Ground Truth Used

The ground truth for the device's performance was established through objective laboratory measurements and analytical validated methods for:

Conductivity (for dissolved salts rejection)
Microbiological assays (for bacteria and endotoxins removal)
Flow rate measurements
Temperature measurements (for heat disinfection)
Material compatibility testing

These methods serve as the "ground truth" to verify the device's output against established standards for water quality.

8. Sample Size for the Training Set

Not applicable. This device is a physical water treatment system, not an AI/ML algorithm that requires a "training set" of data. Its design and operational parameters are based on engineering principles and established reverse osmosis technology, not machine learning.

9. How the Ground Truth for the Training Set Was Established

Not applicable. As there is no training set for an AI/ML algorithm, this question is not relevant to the described device.

Summary

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	K974899 p. 1/5
	510K Notification
	Gambro Central Water Treatment System CWP 100 – WRO H December 23rd, 1997

SEP 23 1998

	510K(k) SUMMARY
SUBMITTER:	Gambro Healthcare1185 Oak StreetLakewood, CO 80215(303) 231-4436
DATE PREPARED:	Friday, December 26, 1997
DEVICE NAME:	Gambro Central Water Treatment SystemCWP 100 – WRO H
CLASSIFICATION NAMES:	Water Purification System for Hemodialysis
PREDICATE DEVICE:	Osmonics Osmo 23 G Series Reverse OsmosisMachines

Device Description:

General Description

In order to ensure that the microbiological quality will be maintained, this system has:

an automated disinfection procedure to keep the membrane surfaces clean and to . minimize bacterial growth;
a hygenic design with smooth surfaces and a minimum of stagnant zones; .
automatic flushing programs at preset intervals when the system is not in use ●

In addition, the WRO H has been designed to reduce water consumption by automatically regulating the pump speed to the actual demand of pure water.

After pretreatment (i.e. sediment filter, water softener, charcoal filter, etc.) the water enters an inlet tank (please refer to position 4 on the following diagram) via a solenoid

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valve (1). The inlet water tank (4) has a float valve (5) and an air gap to help isolate the flowpath from the municipal water system. The main pump (33) then creates a pressure of up to 20 bar that is required for the reverse osmosis process.

Conductivity Monitoring

The conductivity of the inlet water and pure water are continuously monitored by two conductivity cells (32) and are presented on the display on the operator's panel.

Flow Monitoring

The following flow rates are monitored

Flow	Sensor Position	Designation
Inlet Water	3	F1
Reject From the RO Unit	42	F2
Return Pure Water fromthe Clinic	51	F4

These flow rates are used to calculate the following:

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Actual pure water consumption, . (F5=F1-F2)
Outlet pure water flow, . (F6=F1-F2+F4)

All flow rates are presented on the operator's panel on request.

Heat Disinfection Unit

The heat disinfection unit consists of a tank (90) made of stainless steel and an electrical heater (91). The heater maintains the temperature of the pure water in the tank at either 60 ℃ (Low) or 90 ℃ (High). Heat disinfection of the pure water distribution system is initiated by the operator at the end of the dialysis day / session. A circulation pump (96) circulates hot water in the loop until the process is interrupted either manually by the operator, or at a preset time prior to the start of the next dialysis day / session. During the disinfection period, integrated heat disinfection with the dialysis machines can also be performed if the dialysis machines have a heat disinfection capability. The tank automatically refills with pure water from the WRO unit during the next operation. Heating of the water from 60 ℃ (Low) to 90 ℃ (High) takes approximately 2.5 hours if no circulation the loop takes place. During circulation periods the required time is longer because of heat losses and varies depending on the length and design of the system.

Heating Capacity

The heat disinfection unit is capable of maintaining 85 ℃ in a well insulated piping system with a maximum length of 150 meters.

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p.4/5

Predicate Devices:

The Gambro Central Water Treatment System CWP 100 - WRO H is substantially equivalent to other water purification systems for hemodialysis in commercial distribution in the United States to include the Osmonics Osmo 23 G Series Reverse Osmosis Machines (FDA Document Control Number K931595 B. Both systems utilized reverse osmosis for purification of water to be used for hemodialysis. Both systems utilize a polyamide, thin film composite, spiral wound membrane for reverse osmosis. Both systems are intended to be used for water purification for hemodialysis. Both systems utilize substantially equivalent water contact materials for pumps, tubing, and other fittings, etc. Both systems utilize software for control and alarm systems. Both systems come in a number of sizes to accommodate varying product water output requirements. Both systems can utilize chemical disinfection using peracetic acid disinfection products. The Gambro water purification system has the additional advantage of having an integrated heat disinfection capability for both the reverse osmosis system and the distribution system.

We therefore consider the Gambro Central Water Treatment System CWP 100 - WRO H to be substantially equivalent to the Osmonics Osmo 23 G Series Reverse Osmos Machines. The following table provides the necessary information on the predicate device to which this system is substantially equivalent.

DEVICE NAMES	Osmonics Osmo 23 G SeriesReverse Osmosis Machines
INTENDED USE	Water Purification System forHemodialysis
510K NUMBER	K 931595B
APPROVAL DATE	1993

PREDICATE DEVICE

Intended Use:

This indication statement is essentially the same as the indication statement for the predicate device.

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Technological Characteristics:

Comparing the proposed device to the predicate device, some similarities and differences are noted in the design employed to accomplish the same intended use. Both systems utilized reverse osmosis for purification of water to be used for hemodialysis. Both systems utilize a polyamide, thin film composite, spiral wound membrane for reverse osmosis. Both systems are intended to be used for water purification for hemodialysis. Both systems utilize substantially equivalent water contact materials for pumps, tubing, and other fittings, etc. Both systems utilize software for control and alarm systems. Both systems come in a number of sizes to accommodate varying product water output Both systems can utilize chemical disinfection using peracetic acid requirements. disinfection products. The Gambro water purification system has the additional advantage of having an integrated heat disinfection capability for both the reverse osmosis system and the distribution system.

Summary of Non-Clinical Tests:

In vitro performance testing was performed on the Gambro Central Water Treatment Systems to establish normal operating performance to include flow rates, rejection of dissolved salts, organic materials, bacteria, and pyrogen. Additional testing was performed to evaluate the safety of the materials having water contact at various The results of these tests confirmed that the proposed device is temperatures. substantially equivalent to the proposed device for these parameters.

Clinical Test Results:

Clinical testing was not performed

Conclusions:

Testing performed on the Gambro Central Water Treatment System CWP 100 WRO H indicates that they are safe, effective, and perform as well as the predicate device, when used in accordance with the instructions for use.

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Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Jeffrey R. Shideman, Ph.D. GAMBRO Healthcare 1185 Oak Street Lakewood, CO 80215-4498 Re: K974899 GAMBRO Reverse Osmosis System CWP 100-WRO-H Dated: July 7, 1998 Received: July 13, 1998 Regulatory Class: II 21 CFR 876.5665/Procode: 78 FIP

Dear Dr. Shideman:

SEP 2 3 1998

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21. Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (OS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic OS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition. FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (30) ) 594-4613. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address "http://www.fda.gov/cdrh/dsmadsmanan.html".

Sincerely yours.

Lillian Yin, Ph.D.

Director, Division of Reproducti Abdominal, Ear, Nose and Throat and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Intended Use:

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Prescription Use (Per 21 CFR 801.109)

Regulation Number and Section

§ 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.