K Number
K251448

Validate with FDA (Live)

Date Cleared
2026-01-16

(252 days)

Product Code
Regulation Number
868.5450
Age Range
All
Reference & Predicate Devices
Predicate For
N/A
AI/MLSaMDIVD (In Vitro Diagnostic)TherapeuticPediatricDiagnosticis PCCP AuthorizedThirdpartyExpeditedreview
Intended Use

The Flexicare FL-10000U Respiratory Humidifier is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used with the Flexicare Autofill Humidification Chamber and Flexicare Heated Wire Breathing Circuit.

Device Description

FL-10000U is an electrically powered Respiratory Humidifier that actively conditions the inspired respiratory gases delivered to ventilated patients and those receiving respiratory support. It is used as part of a complete system including a Humidification Chamber and either a heated wire breathing system.

FL-10000U Respiratory Humidifier is used with patients who require mechanical ventilation or positive pressure breathing assistance via an endotracheal tube and/or face mask.

The heater plate warms the water in the Humidification Chamber installed on to the top of the device. Gases are warmed and gain humidity in the form of water vapor as they travel along the breathing circuit on the to the patient.

AI/ML Overview

N/A

FDA 510(k) Clearance Letter - FL-10000U Respiratory Humidifier

Page 1

U.S. Food & Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993
www.fda.gov

Doc ID # 04017.08.02

January 16, 2026

Flexicare Medical Limited.
Rebecca Funston
Director of Regulatory Affairs and Quality Assurance
Cynon Valley Business Park Mountain Ash. CF45 4ER.
Rhondda Cynon Taf, Wales CF45 4ER
United Kingdom

Re: K251448
Trade/Device Name: FL-10000U Respiratory Humidifier
Regulation Number: 21 CFR 868.5450
Regulation Name: Respiratory Gas Humidifier
Regulatory Class: Class II
Product Code: BTT
Dated: May 9, 2025
Received: December 11, 2025

Dear Rebecca Funston:

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 (the 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to 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.

Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device"

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K251448 - Rebecca Funston Page 2

(https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).

Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).

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); medical device reporting (reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.

All medical devices, including Class I and unclassified devices and combination product device constituent parts are required to be in compliance with the final Unique Device Identification System rule ("UDI Rule"). The UDI Rule requires, among other things, that a device bear a unique device identifier (UDI) on its label and package (21 CFR 801.20(a)) unless an exception or alternative applies (21 CFR 801.20(b)) and that the dates on the device label be formatted in accordance with 21 CFR 801.18. The UDI Rule (21 CFR 830.300(a) and 830.320(b)) also requires that certain information be submitted to the Global Unique Device Identification Database (GUDID) (21 CFR Part 830 Subpart E). For additional information on these requirements, please see the UDI System webpage at https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/unique-device-identification-system-udi-system.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-devices/medical-device-safety/medical-device-reporting-mdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-devices/device-advice-comprehensive-regulatory-assistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

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K251448 - Rebecca Funston Page 3

Sincerely,

Ethan L. Nyberg -S

Ethan Nyberg, Ph.D.
Assistant Director, Respiratory Devices Team
DHT1C: Division of Sleep Disordered
Breathing, Respiratory and
Anesthesia Devices
OHT1: Office of Ophthalmic, Anesthesia,
Respiratory, ENT and Dental Devices
Office of Product Evaluation and Quality
Center for Devices and Radiological Health

Enclosure

Page 4

DEPARTMENT OF HEALTH AND HUMAN SERVICES
Food and Drug Administration

Form Approved: OMB No. 0910-0120
Expiration Date: 07/31/2026

Indications for Use

See PRA Statement below.

510(k) Number (if known)
K251448

Device Name
FL-10000U Respiratory Humidifier

Indications for Use (Describe)
The Flexicare FL-10000U Respiratory Humidifier is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used with the Flexicare Autofill Humidification Chamber and Flexicare Heated Wire Breathing Circuit.

Type of Use (Select one or both, as applicable)
☒ Prescription Use (Part 21 CFR 801 Subpart D)
☐ Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

Department of Health and Human Services
Food and Drug Administration
Office of Chief Information Officer
Paperwork Reduction Act (PRA) Staff
PRAStaff@fda.hhs.gov

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

FORM FDA 3881 (8/23) Page 1 of 1

Page 5

510(k) Number: K251448
1 / 7

510(k) Summary

(K251448)

Prepared in accordance with the requirements of 21 CFR Part 807.92

Prepared Date: 2026/01/15

1. Submission sponsor

Name: Flexicare Medical Limited
Address: Cynon Valley Business Park Mountain Ash. CF45 4ER. United Kingdom
Contact person: Rebecca Funston
Title: Director of Regulatory Affairs and Quality Assurance
Tel: +44 (0)1443 474647

2. Subject Device Information

Trade/Device NameFL-10000U Respiratory Humidifier
Common NameRespiratory Humidifier
Regulatory ClassClass II
Classification21 CFR 868.5450 / Respiratory Gas Humidifier / BTT
Product codeBTT
Submission typeTraditional 510(K)

3. Predicate Device

No.Device name and model510(K) numberManufacturer
Predicate deviceFlexicare FL-9000U Respiratory Humidifier BaseK161314Flexicare Medical Limited

4. Device Description

FL-10000U is an electrically powered Respiratory Humidifier that actively conditions the inspired respiratory gases delivered to ventilated patients and those receiving respiratory support. It is used as part of a complete system including a Humidification Chamber and either a heated wire breathing system.

FL-10000U Respiratory Humidifier is used with patients who require mechanical ventilation or positive pressure breathing assistance via an endotracheal tube and/or face mask.

The heater plate warms the water in the Humidification Chamber installed on to the top of the device. Gases are warmed and gain humidity in the form of water vapor as they travel along the breathing circuit on the to the patient.

5. Intended use & Indication for use

Page 6

510(k) Number: K251448

510(k) Summary

(K251448)

Prepared in accordance with the requirements of 21 CFR Part 807.92

Prepared Date: 2026/01/15

1. Submission sponsor

Name: Flexicare Medical Limited
Address: Cynon Valley Business Park Mountain Ash. CF45 4ER. United Kingdom
Contact person: Rebecca Funston
Title: Director of Regulatory Affairs and Quality Assurance
Tel: +44 (0)1443 474647

2. Subject Device Information

Trade/Device NameFL-10000U Respiratory Humidifier
Common NameRespiratory Humidifier
Regulatory ClassClass II
Classification21 CFR 868.5450 / Respiratory Gas Humidifier / BTT
Product codeBTT
Submission typeTraditional 510(K)

3. Predicate Device

No.Device name and model510(K) numberManufacturer
Predicate deviceFlexicare FL-9000U Respiratory Humidifier BaseK161314Flexicare Medical Limited

4. Device Description

FL-10000U is an electrically powered Respiratory Humidifier that actively conditions the inspired respiratory gases delivered to ventilated patients and those receiving respiratory support. It is used as part of a complete system including a Humidification Chamber and either a heated wire breathing system.

FL-10000U Respiratory Humidifier is used with patients who require mechanical ventilation or positive pressure breathing assistance via an endotracheal tube and/or face mask.

The heater plate warms the water in the Humidification Chamber installed on to the top of the device. Gases are warmed and gain humidity in the form of water vapor as they travel along the breathing circuit on the to the patient.

5. Intended use & Indication for use

1 / 7

Page 7

510(k) Number: K251448
2 / 7

The Flexicare FL-10000U Respiratory Humidifier is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used with the Flexicare Autofill Humidification Chamber and Flexicare Heated Wire Breathing Circuit.

6. Comparison to the Predicate Device

Table 1: Subject device FL-10000U Respiratory Humidifier Base and Predicate Comparison Table

Subject Device FL-10000U Respiratory Humidifier BaseFlexicare's FL-9000U Respiratory Humidifier BaseComparison
510(k)UnknownK161314-
Indications for useThe Flexicare FL-10000U Respiratory Humidifier Base is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used with the Flexicare Autofill Humidification Chamber and Flexicare Heated Wire Breathing Circuit.The Flexicare FL-9000U Respiratory Humidifier Base is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used only with the Flexicare Heated Wire Breathing System and Flexicare Autofill Humidification Chamber.Same
Product CodeBTTBTTSame
Regulation No.21 CFR 868.545021 CFR 868.5450Same
ClassificationClass IIClass IISame
Supplied/UseRe-usableRe-usableSame
Principle of operationThe device has two heating control units and twoThe device has two heating control units andSame

Page 8

510(k) Number: K251448

The Flexicare FL-10000U Respiratory Humidifier is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used with the Flexicare Autofill Humidification Chamber and Flexicare Heated Wire Breathing Circuit.

6. Comparison to the Predicate Device

Table 1: Subject device FL-10000U Respiratory Humidifier Base and Predicate Comparison Table

Subject Device FL-10000U Respiratory Humidifier BaseFlexicare's FL-9000U Respiratory Humidifier BaseComparison
510(k)UnknownK161314-
Indications for useThe Flexicare FL-10000U Respiratory Humidifier Base is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used with the Flexicare Autofill Humidification Chamber and Flexicare Heated Wire Breathing Circuit.The Flexicare FL-9000U Respiratory Humidifier Base is intended to warm and add humidity to gases delivered to patients requiring mechanical ventilation or positive pressure breathing assistance via an endotracheal tube or face mask. For use by trained personnel only within a hospital/institutional environment. This device is intended to be used only with the Flexicare Heated Wire Breathing System and Flexicare Autofill Humidification Chamber.Same
Product CodeBTTBTTSame
Regulation No.21 CFR 868.545021 CFR 868.5450Same
ClassificationClass IIClass IISame
Supplied/UseRe-usableRe-usableSame
Principle of operationThe device has two heating control units and twoThe device has two heating control units andSame

2 / 7

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510(k) Number: K251448
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Subject Device FL-10000U Respiratory Humidifier BaseFlexicare's FL-9000U Respiratory Humidifier BaseComparison
temperature sensors respectively. Water within a humidification chamber is heated by the device's heating plate and this temperature is controlled by the device with the use of temperature probes. Dry medical gases passing through the chamber gain increased humidity and heat. The supplied Heated wire adaptors supply current to heated wires within breathing tubes that maintain gas temperature travelling to patient. Temperature probes measurement temperature and device controls chamber temperature to achieve desired gas warmth and humidify for patient.two temperature sensors respectively. Water within a humidification chamber is heated by the device's heating plate and this temperature is controlled by the device with the use of temperature probes. Dry medical gases passing through the chamber gain increased humidity and heat. The supplied Heated wire adaptors supply current to heated wires within breathing tubes that maintain gas temperature travelling to patient. Temperature probes measurement temperature and device controls chamber temperature to achieve desired gas warmth and humidify for patient.
Structure and operationThe product consists of FL10000U Respiratory Humidifier, Heated wire adaptor leads (single & dual) and Temperature sensor leads.The product consists of FL9000U Respiratory humidifier, Heated wire adaptor leads (single & dual) and Temperature sensor leads.Same
Mode of operationDevice does not have patient contact. During use it is located between the ventilator and breathing system (between ventilator and patient).Device does not have patient contact. During use it is located between the ventilator and breathing system (between ventilator and patient).Same
Scope of patientDevice intended for patients requiring mechanical ventilation,Device intended for patients requiring mechanical ventilation,Same

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510(k) Number: K251448
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Subject Device FL-10000U Respiratory Humidifier BaseFlexicare's FL-9000U Respiratory Humidifier BaseComparison
positive pressure breathing support or other respiratory support requiring controlled heat and humiditypositive pressure breathing support or other respiratory support requiring controlled heat and humidity
Electric lightning protectionClass IClass ISame
Applied partType BType BSame
Drip proofIPX 1IPX 1Same
Target populationAny patient requiring active humidificationAny patient requiring active humidificationSame
Housing materialPolycarbonatePolycarbonateSame
Temp sensingYSIYSISame
Heating MethodPass overPass overSame
Heated Wire control on/offYesYesSame
Single/dual/non heated wire compatibleYesYesSame
Dimensions156mm × 170mm × 130mm156mm × 170mm × 130mmSame
Weight2.9kg2.9kgSame
Supply frequency50/60 Hz50/60 HzSame
Supply voltage115V~115V~Same
Supply current2.0 A max at 115V~2.0 A max at 115V~Same
Heater plate150 W150 WSame
Heater plate over temperature cutout115 ± 3°C115 ± 3°CSame
Safety cutoff software110°C110°CSame
Heater Wire22V~, 2.73A, 60W, 50/60Hz22V~, 2.73A, 60W, 50/60HzSame

Temperature control settings (heater wire)

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Subject Device FL-10000U Respiratory Humidifier BaseFlexicare's FL-9000U Respiratory Humidifier BaseComparison
AirwayInvasive: Default: 40°C, Range: 38-40°C Non-invasive: Default: 34°C, Range: 31-34°CInvasive: Default: 40°C, Range: 36-40°C Non-invasive: Default: 34°C, Range: 31-35°CSimilar
Chamber outletInvasive: Default:37°C, Range: 35-37°C Non-invasive: Default: 31°C, Range: 30-34°CInvasive: Default: 37°C Range: 34-40°C Non-invasive: Default: 31°C Range: 31-35°CSimilar

Alarm Parameters

High Humidity Alarm

Alarm parameterAirway: High alarm Chamber: High alarm / Low alarmAirway: High alarm / Low alarm Chamber: High alarm / Low alarmSimilar
Display temperature of 41℃YesYesSame
Airway Temperature exceeds 43℃YesYesSame

Low Humidity Alarm

60 minutes @ 34.5 °CYesYesSame
10 minutes @ 29.5 °CYesYesSame
Sound Pressure LevelAlarms exceed 50 dBA @ 1mAlarms exceed 50 dBA @ 1mSame

Performance

Recommended ambient Temperature range18 - 26°C18 - 26°CSame
Recommended Flow rangeInvasive: Min 1.5 lpm at a PEEP ≥ 3 cmH₂O Non-Invasive: Max 60 lpmInvasive: Up to 60 L/min Non-invasive: Up to 120 L/minDifferent
HumidityInvasive: >33mg/LInvasive: >33mg/LSame

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Subject Device FL-10000U Respiratory Humidifier BaseFlexicare's FL-9000U Respiratory Humidifier BaseComparison
performanceNon-invasive: >10mg/LNon-invasive: >10mg/L
Warm-up timeLess than 30 minutesLess than 30 minutesSame
Standard and ApprovalsIEC 60601-1 IEC 60601-1-2 ISO 80601-2-74 ISO 10993-1 IEC 62366-1 IEC 62304 ISO 3744 IEC 60529EN 60601-1 EN 60601-1-2 EN ISO 8185 EN ISO 10993-1,3,5,6,10 EN 62366 EN 62304 ISO 3744 BS EN 60529Equivalent, ISO 8185 is replaced by newest version ISO 80607-2-74

7. Non-clinical Data

The following performance data were provided in support of the substantial equivalence determination.

Biocompatibility testing

Biocompatibility of the subject device was evaluated in accordance with the FDA guidance "Use of International Standard ISO 10993-1, "Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process" and International Standard ISO 10993-1 "Biological Evaluation of Medical Devices − Part 1: Evaluation and Testing Within a Risk Management Process," and ISO 18562-1" Biocompatibility evaluation of breathing gas pathways in healthcare applications - Part 1: Evaluation and testing within a risk management process" as recognized by FDA, FDA's guidance document on Use of International Standard ISO 10993-1, "Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process",2023. Testing of the subject device demonstrates an appropriate biocompatibility profile for the device.

Electrical safety, electromagnetic compatibility (EMC) and Alarms

Electrical safety and EMC testing were conducted on the subject device. The system complies with the ANSI AAMI ES60601-1:2005/(R)2012 & A1:2012, C1:2009/(R)2012 & A2:2010/(R)2012 (Cons. Text) [Incl. AMD2:2021] for safety and the IEC 60601-1-2:2014 + AMD1:2020 Ed 4.1 for EMC. Alarms testing was performed in accordance with IEC 60601-1-8:2006+AMD1:2012+AMD2:2020.

Bench performance testing

Performance testing was conducted to demonstrate substantial equivalence including:
• ISO 80601-2-74 Second edition 2021-07 Medical electrical equipment - Part 2-74:

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Particular requirements for basic safety and essential performance of respiratory humidifying equipment

8. Clinical study

Not applicable.

9. Conclusion

Performance testing and compliance with voluntary standards demonstrate that the subject device is substantially equivalent to the predicate device.

7 / 7

§ 868.5450 Respiratory gas humidifier.

(a)
Identification. A respiratory gas humidifier is a device that is intended to add moisture to, and sometimes to warm, the breathing gases for administration to a patient. Cascade, gas, heated, and prefilled humidifiers are included in this generic type of device.(b)
Classification. Class II (performance standards).