The City Technology Medical replacement oxygen sensor is intended to replace the original oxygen-sensing component of an oxygen analyzer that measures oxygen concentration in breathing gas mixtures.

Device Description

These medical Oxygen sensors are based on the amperometric electrochemical measurement principle. The sensors comprise a plastic body in which are two electrodes, a precious metal cathode and a lead anode immersed in a liquid electrolyte solution. Oxygen flows into the sensor through a solid membrane, which limits the flow and controls the output signal. Inside the sensor Oxygen reacts on the cathode to form hydroxyl ions. These hydroxyl ions then oxidise the metal anode. The electrons consumed at the cathode are supplied from the anode via the external circuit where a resistor is placed so that the voltage produced may be monitored. This voltage signal then constitutes a measure of the flux of Oxygen into the sensor and hence the partial pressure of Oxygen in front of the membrane.

AI/ML Overview

This document describes the City Technology Medical Oxygen Sensors (MOX-1 through MOX-16), which are oxygen-sensing components designed to monitor oxygen concentration in breathing gas mixtures within medical devices like anesthesia machines, intensive care units, and incubators. The submission is for a 510(k) premarket notification, aiming to demonstrate substantial equivalence to a legally marketed predicate device.

Here's an analysis of the acceptance criteria and the study details:

1. Table of Acceptance Criteria and Reported Device Performance:

The document doesn't explicitly state "acceptance criteria" as a separate section with pass/fail thresholds. Instead, it presents a comparison table between the predicate device (Ceramatec CAG-10 Sensor) and the City Technology Medical Oxygen Sensors. The implication is that the City Technology sensors demonstrate performance at least equivalent to, or better than, the predicate device.

Performance Characteristic	Predicate Device (CAG-10)	CTL MOX-1, 2, 3, 4, 7, 8 & 10	CTL MOX-5, 6 and 9	CTL MOX-16
Measurement Range	0-100%	0-1500 mBar	0-1500 mBar	0-1500 mBar
T90 (Response Time to 90% of Signal)	<15s	<15s	<15s	<15s
Operating Temperature Range	10-40°C	-20°C - +50°C	-20°C - +50°C	-20°C - +50°C
Operating Humidity Range	10-95% RH	0-99%RH	0-99% RH	0-99% RH
Cross-Interference to Anesthesia Agent Gases	<1%	<±2%	<±2%	<±2%
Linearity	±2%	R2>0.9999	R2>0.9999	R2>0.9999
Operating Life	>900,000 %O2 Hours	1,600,000 %O2 Hours	>900,000 %O2 Hours	>650,000 %O2 Hours

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

The document does not specify the sample size used for performance testing. It presents performance characteristics as general specifications for the device families. There is also no information about the data provenance (e.g., country of origin, retrospective or prospective nature of studies).

3. Number of Experts Used to Establish Ground Truth and Qualifications:

This information is not applicable to this document. The device is a sensor (hardware component) measuring a physical quantity (oxygen concentration). The "ground truth" would be established by validated reference instruments or gas mixtures of known concentration, not by human experts.

4. Adjudication Method for the Test Set:

This information is not applicable for the same reasons as point 3.

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

This information is not applicable. The device is a standalone sensor, not an AI-assisted diagnostic tool that would involve human readers interpreting images or data.

6. Standalone Performance Study:

Yes, a standalone performance assessment was conducted for the device. The table in point 1 presents the standalone performance characteristics of the City Technology Medical Oxygen Sensors. The device's operation is based on an amperometric electrochemical measurement principle, and its performance (e.g., T90, linearity, operating life, cross-interference) was evaluated and reported in comparison to the predicate device.

7. Type of Ground Truth Used:

The ground truth for evaluating the sensor's performance would have been established using known gas concentrations or calibrated reference instruments. For example, to assess linearity, the sensor would be exposed to various oxygen concentrations (e.g., 0%, 21%, 100% oxygen) and its output compared to the known values. Similarly, for cross-interference, the sensor would be exposed to specific interfering gases at known concentrations, and the impact on the oxygen reading would be measured. This implicitly relies on physical standards and calibrated equipment rather than expert consensus, pathology, or outcomes data.

8. Sample Size for the Training Set:

This information is not applicable. The MOX sensors are electrochemical sensors based on a well-understood physical principle. They are not AI/ML-based devices that require a "training set" in the computational sense. Their function is directly derived from their physical design and material properties.

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

This information is not applicable for the same reasons as point 8.

Summary

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Section 21

'JUL 1 5 2004

510(k) Summary

Date: 6th April 2004 1.
1. Submitter/Manufacturer City Technology Limited City Technology Centre Walton Road Portsmouth Hampshire PO6 1SZ Great Britain
1. Contact Person Debra Wallace Quality/Environmental Systems Scientist

4. Contact
Telephone:	+44 23 9232 5511
Fax:	+44 32 9238 6611
E-mail:	debra.wallace@citytech.co.uk
Website:	www.citytech.com

1. Proprietary Device Name MOX-1 Medical Oxygen Sensor MOX-2 Medical Oxygen Sensor MOX-3 Medical Oxygen Sensor MOX-4 Medical Oxygen Sensor MOX-5 Medical Oxygen Sensor MOX-6 Medical Oxygen Sensor MOX-7 Medical Oxygen Sensor MOX-8 Medical Oxygen Sensor MOX-9 Medical Oxygen Sensor MOX-10 Medical Oxygen Sensor MOX-16 Medical Oxygen Sensor
్. Classification Name Oxyqen Gas Analyzer (868.1720)
1. Common Name Medical Oxygen Sensor
1. Predicate Devices Ceramatec CAG-10 Sensor

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ഗ Indications for Use
Purpose: The purpose of the City Technology Medical Oxygen sensors is to be the oxygen-sensing component to monitor the concentration of oxygen in breathing gas mixtures in finished medical devices at the point of manufacture. The additional purpose of the City Technology Medical Oxygen sensors is to be a replacement for the oxygen-sensing component after the life of the sensor originally supplied in the device is exhausted, to monitor the concentration of oxygen in breathing gas mixtures in medical devices.

Function: The City Technology Medical Oxygen sensors are used in medical device products such as Anaesthesia, Intensive Care and Incubators.

Target Patient Population: The target patient population consists of those patients who require the oxygen concentration in their breathing environment to be monitored.

Environment of Use: The City Technology Medical Oxygen Sensors are used in medical devices (i.e. Anaesthesia, Intensive Care and Incubators) in patient environments whose temperatures range from -20°C to +50°C and from 0 to 99% humidity (non-condensing).

Device Claims: The City Technology Medical Oxygen Sensors consist of oxygen sensing components in medical devices that monitor the oxygen concentration in the patient's breathing environment.

Legally Marketed Predicate Device: The legally marketed predicate device is Ceramatec CAG-10 Oxygen Sensor. The predicate device was assigned 510(k) number K972992 and was declared substantially equivalent by FDA.

Safety and Effectiveness: No differences in intended use or application of the City Technology Medical Oxygen sensors or the predicate device have been identified that could affect safety or effectiveness.

1. Method of Operation:
  These medical Oxygen sensors are based on the amperometric electrochemical measurement principle. The sensors comprise a plastic body in which are two electrodes, a precious metal cathode and a lead anode immersed in a liquid electrolyte solution, as in the schematic below.

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Image /page/2/Figure/0 description: This image shows a diagram of a solid membrane diffusion barrier. The diagram includes labels for the different components of the barrier, including the solid membrane diffusion barrier, cathode, electrolyte, and anode. The diagram also shows the direction of air supply and the flow of electrons. A load resistor and voltmeter are connected to the cathode and anode.

Oxygen flows into the sensor through a solid membrane, which limits the flow and controls the output signal. Inside the sensor Oxygen reacts on the cathode to form hydroxyl ions as follows:

$$O_2 + 2H_2O + 4e^- \longrightarrow 4OH^-$$

These hydroxyl ions then oxidise the metal anode:

$2Pb + 4OH^- \longrightarrow 2PbO + 2H_2O + 4e^-$

Overall the effect is the consumption of the lead anode:

$$2Pb + O_2 \longrightarrow 2PbO$$

The electrons consumed at the cathode are supplied from the anode via the external circuit where a resistor is placed so that the voltage produced may be monitored. This voltage signal then constitutes a measure of the flux of Oxygen into the sensor and hence the partial pressure of Oxygen in front of the membrane.

The life of the sensor is governed by the mass of lead and the rate of consumption i.e. by the oxygen partial pressure; hence lifetimes are quoted as % Oxygen hours.

Accuracy is governed largely by the variation in diffusion rate of Oxygen through the solid membrane, which is a function of temperature and the presence of interfering gases that may absorb onto the membrane.

1. Intended Use
  These sensors are designed to be used to monitor the partial pressure of oxygen in anaesthesia, critical care, incubators and general oxygen monitors.

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Predicate Device Comparison 12.

	PredicateDeviceCAG-10	CTL MOX-1,2, 3, 4, 7, 8& 10	CTL MOX-5,6 and 9	CTLMOX-5	CTL MOX-16
MeasurementRange	0-100%	0-1500mBar	0-1500mBar	0-1500mBar	0-1500mBar
T90	<15s	<15s	<15s	<20s	<15s
OperatingTemperatureRange	10-40°C	-20°C -+50°C	-20°C -+50°C	-20°C -+50°C	-20°C -+50°C
OperatingHumidityRange	10-95% RH	0-99%RH	0-99% RH	0-99% RH	0-99% RH
Cross-InterferencetoAnaesthesiaAgent Gases	<1%	<±2%	<±2%	<±2%	<±2%
Linearity	±2%	R2>0.9999	R2>0.9999	R2>0.9999	R2>0.9999
Operating Life	>900,000%O2 Hours	1,600,000 %O2 Hours	>900,000%O2 Hours	>900,000%O2Hours	>650,000%O2 Hours

The MOX-1, 2, 3, 4, 7, 8 and 10 Sensors differ only in body shape and electrical interface type, but are otherwise identical and can be considered equivalent.

The MOX-5, 6 and 9 Sensors differ only in body shape and electrical interface type, but are otherwise identical and can be considered equivalent.

The MOX-16 sensor is a dual cathode version of the other Medical Oxygen Sensors. It also has a different body shape and electrical interface, but otherwise it is identical and can therefore be considered equivalent.

1. Conclusion
  City Technology's Medical Oxyqen Sensors are substantially equivalent to the predicate devices listed. Medical Oxygen Sensors are safe and effective for their intended use.

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Image /page/4/Picture/1 description: The image shows the seal of the Department of Health & Human Services (HHS). The seal features a stylized eagle with three stripes representing the three levels of government: federal, state, and local. The eagle is encircled by the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" in a circular arrangement.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JUL 1 5 2004

City Technology Limited C/O Jeff D. Rongero Underwriters Laboratories, Incorporated 12 Laboratory Drive Research Triangle, NC 27709

Re: K041773

Trade/Device Name: Medical Oxygen Sensors, MOX -1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 16 Regulation Number: 868.1720 Regulation Name: Oxygen Gas Analyzer Regulatory Class: II Product Code: CCL Dated: June 25, 2004 Received: July 1, 2004

Dear Mr. Rongero:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate 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) that do not require approval of a premarket approval application (PMA). 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 II (Special Controls) or class III (PMA), 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 898. In addition. FDA may publish further announcements concerning your device in the Federal Register.

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Page 2 - Mr. Rongero

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050. This letter will allow you to begin marketing your device as described in your Section 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), please contact the Office of Compliance at (301) 594-4646. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.

Sincerely yours,

Kein Muluy
Chiu Lin, Ph.D.

Director Division of Anesthesiology, General Hospital, Infection Control and Dental Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications for Use

K041773 510(k) Number (if known):

Device Name:

MOX-1,2,3,4,5,6,7,8,9,10 and 16 Medical Oxygen Sensors

Indications For Use: The City Technology Medical replacement oxygen sensor is intended to replace the original oxygen-sensing component of an oxygen analyzer that measures oxygen concentration in breathing gas mixtures.

Prescription Use X (Per 21CFR 801.109) OR

Over-The-Counter Use __ www

(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Quy Syuun

Page I of 1

(Division Sign-Off) (Division Sign-Oil)
Division of Anesthesiology, General Hospital, Division Control, Dental Devices

FD 1030 Issue 1

510(k) Number

(Posted November 13, 2003)

Regulation Number and Section

§ 868.1720 Oxygen gas analyzer.

(a)
Identification. An oxygen gas analyzer is a device intended to measure the concentration of oxygen in respiratory gases by techniques such as mass spectrometry, polarography, thermal conductivity, or gas chromatography. This generic type of device also includes paramagnetic analyzers.(b)
Classification. Class II (performance standards).