Your Contact to Sensirion

Umschlag

Contact

Contact our sensor experts:

Please contact us

Distributoren

Distributors & Representatives

Here you find the nearest distributor and/or representative in your area.

Learn more

Support Center

Please find here an overview of various support topics:

Go to Support Center

Standorte

Locations

Find out where we are located:

Our Locations

toggle menu
  • Home
  • Environmental Sensors
    • Humidity Sensors
      • Digital Humidity Sensor SHT4x (RH/T)
      • Digital Humidity Sensor SHT3x (RH/T)
      • Digital Humidity Sensor SHT85 (RH/T)
      • Digital Humidity Sensor SHTC3 (RH/T)
      • Digital Humidity Sensor SHTC1 (RH/T)
      • Digital Humidity and Temperature Module SCC30-DB (RH/T)
      • SF2 Filter Cap
      • SHT31 Smart Gadget Development Kit
      • Digital Humidity Sensor SHTW2 (RH/T) (NRND)
    • Temperature Sensors
      • Temperature Sensor STS3x
      • Temperature Sensor STS32
    • Multi-Pixel Gas Sensors SGP
      • VOC Sensor SGP40
      • VOC Sensor SGP30 / SGPC3 (NRND)
      • Multi-Gas, Humidity and Temperature Module SVM30 (NRND)
    • Particulate Matter Sensor SPS30
    • Carbon Dioxide Sensors
      • Carbon Dioxide Sensor SCD4x
      • Carbon Dioxide Sensor SCD30
      • Carbon Dioxide Sensor STC31
    • Formaldehyde Sensor Module SFA30
    • Nubo Air
    • Evaluation Kit SEK-Environmental Sensing
      • Evaluation Kit SEK-SCD41
      • Evaluation Kit SEK-SVM40
      • Evaluation Kit SEK-SFA30
    • Download Center
    • Support Center
    • Shop
  • Flow Sensors
    • Liquid Flow Meters
      • Lx – Compact Liquid Flow Meters
        • Liquid Flow Meter LG16
        • Liquid Flow Meter LG01
        • Liquid Flow Meter LS32-1500
      • SLx – Standalone Liquid Flow Meters
        • Liquid Flow Meter SLI
        • Liquid Flow Meter SLG
        • Liquid Flow Meter SLQ-QT105
        • Liquid Flow Meter SLQ-QT500
        • Liquid Flow Meter SLS-1500
      • Liquid Flow Sensor SLF3x
      • Liquid Flow Sensor LPG10
      • Liquid Flow Sensor LD20
      • Liquid Flow Meter Kits
      • Customized (OEM) Liquid Flow Meters
    • Mass Flow Meters for Gases
      • Mass Flow Meter SFM3000
      • Mass Flow Meters SFM3003 and SFM3013
      • Mass Flow Meter SFM3019
      • Mass Flow Meter SFM3100
      • Mass Flow Meter SFM3119
      • Mass Flow Meter SFM3200
      • Mass Flow Meter SFM3300
      • Mass Flow Meter SFM3400
      • Mass Flow Meter SFM4100
      • Mass Flow Meter SFM4200
      • Mass Flow Meter SFM4300
      • Mass Flow Meter SFM5300
      • Mass Flow Meter SFM5400
      • Mass Flow Meter Evaluation Kits
      • Customized (OEM) Mass Flow Meters
    • Mass Flow Controllers for Gases
      • Mass Flow Controller SFC5400
      • Mass Flow Controller SFC5300
      • Customized (OEM) Mass Flow Controllers
      • Evaluation Kit EK-F5x
    • Gas Sensors
    • Differential Pressure Sensors
      • Differential Pressure Sensor SDP3x
      • Differential Pressure Sensors SDP800 Series
      • Differential Pressure Sensor SDP2000
      • Fail-Safe Integration with Differential Pressure Sensors
      • Evaluation Kit EK-P4
      • Evaluation Kit EK-P5
    • Download Center
    • Support Center
    • Shop
    • Evaluation Kit SEK-Flow Sensing
  • Markets
    • Automotive
    • Industrial
      • Life Sciences, Diagnostics and Analytical Instruments
      • H2 Measurement
    • Medical
      • Ventilation
    • Consumer
  • About us
    • Sensirion – The Sensor Company
      • Company
      • Locations
      • Growth Drivers
      • Distribution Network
      • Executive Committee
      • Board of Directors
      • CMOSens® Technology
      • MOXSens® Technology
      • PASens® Technology
    • Newsroom
      • News and Press Releases
      • Trade Fairs 2021
      • Newsletter
      • Specialist Articles
      • Webinars
    • Brand Experience Portal
    • Sensirion Automotive Solutions
    • Investor Relations
    • Quality & Sustainability
    • Supplier Portal
    • Support Center
    • Partner Access
  • Career
    • Your Start
      • Professionals
      • Graduates
      • Students
      • Apprentices
      • Job Profiles
    • Career Openings
      • Employee
      • Internship
      • Apprentice
      • Sensirion Student Pool
      • Login applicant's portal
    • Employer Sensirion
      • Your Workplace
      • Our Values
      • Success Stories
      • Benefits
      • Career Opportunities
      • Employees Tell Their Stories
      • Career Videos
    • Great Place to Work®
    • Career Events 2021
    • Career News
    • Job Newsletter
    • Alumni Group
    • Student Ambassadors
    • Contact Recruiting Manager
  • Developers
  • ENG
  • DEU
  • CHI
  • JPN

No translation available

Sorry, this page is not available in English.

Continue to home page

Keine Übersetzung verfügbar

Leider ist diese Seite nicht in Deutsch verfügbar.

Weiter zur Startseite

本页没有翻译

抱歉,本页没有英文翻译

继续浏览主页

和訳はありません

申し訳ありません。このページの和訳はありません

ホームページに戻る

    Contact

    search
    cart
    DOWNLOAD CENTER BUY NOW INVESTORS
    Sensirion AG Switzerland
    • Home
    • Environmental Sensors
      • Humidity Sensors
        • Digital Humidity Sensor SHT4x (RH/T)
        • Digital Humidity Sensor SHT3x (RH/T)
        • Digital Humidity Sensor SHT85 (RH/T)
        • Digital Humidity Sensor SHTC3 (RH/T)
        • Digital Humidity Sensor SHTC1 (RH/T)
        • Digital Humidity and Temperature Module SCC30-DB (RH/T)
        • SF2 Filter Cap
        • SHT31 Smart Gadget Development Kit
        • Digital Humidity Sensor SHTW2 (RH/T) (NRND)
      • Temperature Sensors
        • Temperature Sensor STS3x
        • Temperature Sensor STS32
      • Multi-Pixel Gas Sensors SGP
        • VOC Sensor SGP40
        • VOC Sensor SGP30 / SGPC3 (NRND)
        • Multi-Gas, Humidity and Temperature Module SVM30 (NRND)
      • Particulate Matter Sensor SPS30
      • Carbon Dioxide Sensors
        • Carbon Dioxide Sensor SCD4x
        • Carbon Dioxide Sensor SCD30
        • Carbon Dioxide Sensor STC31
      • Formaldehyde Sensor Module SFA30
      • Nubo Air
      • Evaluation Kit SEK-Environmental Sensing
        • Evaluation Kit SEK-SCD41
        • Evaluation Kit SEK-SVM40
        • Evaluation Kit SEK-SFA30
      • Download Center
      • Support Center
      • Shop
      • Formaldehyde Sensor SFA30

        Formaldehyde Sensing Made Easy

        The SFA30 is Sensirion’s new digital formaldehyde sensor designed for easy integration into air purifiers, demand-controlled ventilation systems, or indoor air quality monitors. Based on Sensirion’s electrochemical technology, the SFA30 offers excellent formaldehyde sensing performance with a uniquely low cross-sensitivity to other VOCs. The sensor module’s on-board SHT sensor provides accurate humidity and temperature readings and enables a fully temperature/humidity compensated and factory calibrated formaldehyde concentration output in ppb.

        More

    • Flow Sensors
      • Liquid Flow Meters
        • Lx – Compact Liquid Flow Meters
          • Liquid Flow Meter LG16
          • Liquid Flow Meter LG01
          • Liquid Flow Meter LS32-1500
        • SLx – Standalone Liquid Flow Meters
          • Liquid Flow Meter SLI
          • Liquid Flow Meter SLG
          • Liquid Flow Meter SLQ-QT105
          • Liquid Flow Meter SLQ-QT500
          • Liquid Flow Meter SLS-1500
        • Liquid Flow Sensor SLF3x
        • Liquid Flow Sensor LPG10
        • Liquid Flow Sensor LD20
        • Liquid Flow Meter Kits
        • Customized (OEM) Liquid Flow Meters
      • Mass Flow Meters for Gases
        • Mass Flow Meter SFM3000
        • Mass Flow Meters SFM3003 and SFM3013
        • Mass Flow Meter SFM3019
        • Mass Flow Meter SFM3100
        • Mass Flow Meter SFM3119
        • Mass Flow Meter SFM3200
        • Mass Flow Meter SFM3300
        • Mass Flow Meter SFM3400
        • Mass Flow Meter SFM4100
        • Mass Flow Meter SFM4200
        • Mass Flow Meter SFM4300
        • Mass Flow Meter SFM5300
        • Mass Flow Meter SFM5400
        • Mass Flow Meter Evaluation Kits
        • Customized (OEM) Mass Flow Meters
      • Mass Flow Controllers for Gases
        • Mass Flow Controller SFC5400
        • Mass Flow Controller SFC5300
        • Customized (OEM) Mass Flow Controllers
        • Evaluation Kit EK-F5x
      • Gas Sensors
      • Differential Pressure Sensors
        • Differential Pressure Sensor SDP3x
        • Differential Pressure Sensors SDP800 Series
        • Differential Pressure Sensor SDP2000
        • Fail-Safe Integration with Differential Pressure Sensors
        • Evaluation Kit EK-P4
        • Evaluation Kit EK-P5
      • Download Center
      • Support Center
      • Shop
      • Evaluation Kit SEK-Flow Sensing
      • Product Highlight

        Evaluation kit for the single-use liquid flow sensor LD20-2600B

        The LD20-2600B single-use liquid flow sensor for fast, precise and reliable measurements of the lowest flow rates in biomedical applications was successfully launched three years ago. The evaluation kit for this OEM liquid flow sensor can now also be purchased online via Sensirion's distribution network.

        Read more

    • Markets
      • Automotive
      • Industrial
        • Life Sciences, Diagnostics and Analytical Instruments
        • H2 Measurement
      • Medical
        • Ventilation
      • Consumer
      • Our Markets

        Sensirion Markets Icons

        Experts for Smart Sensor Solutions

        Sensirion's sensors are used in a wide range of markets and different applications. Our high-quality environmental and flow sensors and sensor solutions improve energy efficiency and sustainability. They increase our safety, support our health and raise the quality of life. 

        Read more

    • About us
      • Sensirion – The Sensor Company
        • Company
        • Locations
        • Growth Drivers
        • Distribution Network
        • Executive Committee
        • Board of Directors
        • CMOSens® Technology
        • MOXSens® Technology
        • PASens® Technology
      • Newsroom
        • News and Press Releases
        • Trade Fairs 2021
        • Newsletter
        • Specialist Articles
        • Webinars
      • Brand Experience Portal
      • Sensirion Automotive Solutions
      • Investor Relations
      • Quality & Sustainability
      • Supplier Portal
      • Support Center
      • Partner Access
      • Sensirion – The Sensor Company

        Sensirion Worldmap

        Sensirion Worldwide

        Founded in 1998 Sensirion has become the leading manufacturer of flow and environmental sensors solutions. The company now employs people in various countries such as the USA, South Korea, Japan, China, Taiwan, and Germany. The headquarters in Switzerland is responsible for research, development, and production. 

        Read more

    • Career
      • Your Start
        • Professionals
        • Graduates
        • Students
        • Apprentices
        • Job Profiles
      • Career Openings
        • Employee
        • Internship
        • Apprentice
        • Sensirion Student Pool
        • Login applicant's portal
      • Employer Sensirion
        • Your Workplace
        • Our Values
        • Success Stories
        • Benefits
        • Career Opportunities
        • Employees Tell Their Stories
        • Career Videos
      • Great Place to Work®
      • Career Events 2021
      • Career News
      • Job Newsletter
      • Alumni Group
      • Student Ambassadors
      • Contact Recruiting Manager
      • Most Popular Employer in Switzerland 2019

        Learn more: www.sensirion.com/GPTW

         

        Top Career Openings:

        • R&D Engineer MEMS
        • Senior Software Engineer 80-100%
        • Office Manager HR and Administration


        All our career openings

    • Developers
    Sensirion AG Switzerland
    • Sensirion Medical Application

      Gas Flow Sensing Technology in Medical Ventilation Devices

      Specialist Article

    • Home
    • About us
    • Newsroom
    • Specialist Articles

    Gas Flow Sensing Technology in Medical Ventilation Devices

    Author: Daniel Träutlein, Market Manager Medical

    Sensors are used to measure gas flows for various purposes in modern medical ventilation technology. A variety of measuring principles are used, depending on the manufacturer and the intended use. Many different sensor products are now available on the market. Medical ventilation technology has made rapid progress since the invention of the "iron long" about 80 years ago - the first device used for patient ventilation. Along with pressure sensors, flow sensing technology and gas flow sensors play a significant role today. The original iron lung used negative pressure to achieve patient ventilation, but modern devices use positive pressure in the patient's lungs for this purpose. Along with air, other gases - primarily oxygen - are also used for ventilation. The quantity and mixture of the various gases are precisely controlled and monitored using sensor systems. The requirements on sensor systems vary greatly, depending on where and how the ventilation device is used.

    Diverse application areas

    Medical ventilation devices can basically be divided into three application areas: devices for emergency treatment, devices for intensive care, and devices for home use. Naturally, each area and each individual device has its own specific features. The key considerations with emergency treatment devices are size and weight, since it must be possible to bring them to patients quickly and easily. They usually operate from battery power to make them independent of the AC power line. Ventilation devices for intensive care are used in hospitals and operated by medical staff. They have a significantly greater functional scope than devices for emergency treatment. The main consideration with these devices is their performance capability. Finally, ventilation devices for home use must ensure proper breathing for patients who are not able to breathe adequately on their own.

    Manifold requirements for flow sensing technology

    The previously mentioned three application areas for ventilation technology lead to diverse requirements for flow sensors. In emergency treatment devices, the pressure drop due to the flow resistance of the sensor in the gas stream should be as small as possible. This is because a high pressure drop means more work for the turbine that generates the positive pressure for the patient. A low pressure drop therefore translates into longer battery service life or a smaller battery, which has a beneficial effect on size or weight.

    In intensive care, the desire to be able to use the device in the greatest possible variety of setting imposes additional requirements on flow sensing technology. For instance, it should be possible to use the same device for all patients, regardless of whether they are infants or adults. The greatest possible dynamic range and high sensor resolution ensure that the device can be used for patients of different sizes. For example, modern flow sensors should ideally be able to measure flow volumes up to 250 liters per minute, while still being able to detect volumes less than 1 liter with high precision. Along with this wide dynamic measuring range, measurement accuracy with low gas flows in particular is a crucial aspect. A short sensor response time is also necessary, since various ventilation modes are used in intensive care. A common aspect of all areas is that the sensors must be robust and have the best possible long-term stability, in order to minimize recalibration and maintenance effort.

    Other requirements for sensor technology result from the various functions that are used to control or monitor the sensors. A distinction is made between inspiration sensors, expiration sensors and patient-side sensors (spirometry). Sensors on the inspiration side (breathing in) are installed in the device. They are distant from the patient, and the gas always flows from the sensor to the patient (never the other direction). The gas is clean and dry. By contrast, sensors on the expiration side measure the air that is breathed out. This air is moist and comes from the patient. The third area - patient-side sensors - has the most severe requirements. Patient-side sensors must either be suitable for reconditioning, which means cleaning and autoclaving, or disposable. In addition, patient-side sensors must be able to measure both inspiration and expiration, which makes bidirectional calibration essential. This is a major challenge for some types of sensors, in particular hot-wire anemometers. If patient ventilation extends over a relatively long time, weaning creates special challenges for the sensor system if the patient's breathing must be assisted. The onset of breathing must be detected by the device without any time delay.

    Various measuring principles

    A variety of measuring principles are used for flow measurement in ventilation technology. Due to accuracy requirements and the progressive integration of electronic control systems, the floating-body flow gauges previously used on a wide scale are now only found in older devices.

    Differential pressure sensors are used for flow measurement in many devices. This allows the differential pressure sensor to be located relatively far away from the patient and still determine the flow close to the patient. The accuracy of this measuring method does not depend directly on the sensor, but instead on the combination of the differential pressure sensor and the component used to obtain the pressure drop, which is usually an orifice or a linear flow element. The hose between the flow element and the sensor is also a significant factor. The hose basically has an attenuating effect, so kinks in the hose should be avoided.

    There are also sensors available that use ultrasonic signals to make "time of flight" measurements. The actual sensor measures through a plastic wall. Easy reconditioning is one of the advantages of this method. However, it entails much higher manufacturing costs.

    There are also thermal measuring principles. With the thermal methods, we can distinguish between conventional hot-wire anemometers and hot-film anemometers. A drawback of hot-wire anemometers is that only the magnitude of the gas flow is measured. It is not possible to indicate the direction. This drawback can be eliminated by using hot-film anemometers with several zones.

    Sensirion's CMOSens® Technology

    Sensirion's CMOSens® mass flow sensors represent a refinement of the thermal measurement method. In the mass flow sensor, the temperature sensors are arranged symmetrically around a heating element. This allows the flow direction to be determined and enables precise bidirectional measurement. Integration of the sensor and the analog and digital signal processing circuitry on a microchip enables precise calibration and temperature compensation of flow measurement. The sensor element and processing with calibration data allow the measurement signal to be processed quickly. Other information about the gas flow can also be obtained, depending on the gas or gas mixture. If the gas consists of a mixture of two pure gases with different thermal properties, the mixing ratio can be determined in addition to the flow. This signal is used in ventilation technology for purposes such as measuring nitrous oxide / air mixtures or helium/oxygen mixtures. However, it can also be used as a redundant signal if the mixture is regulated by other flow sensors.

    In addition to pure flow sensors, mass flow controllers are available. Mass flow controllers have a built-in valve, and they are an especially attractive option for smaller manufacturers because the cost of developing the same capability in-house can be considerable. A ready-made solution also reduces time to market for the product. However, mass flow controllers for ventilation technology must be significantly faster than those for industrial applications, since they have to be able to follow the patient's breathing.


    Print Version of the Specialist Article

    • Specialist Article - Gas Flow Sensing Technology in Medical Ventilation Devices
    • Fachartikel - Gasflussensorik in Beatmungsgeräten

    Related Products to This Article

    Sensirion Mass Flow Meters SFM3000

    Mass Flow Meter SFM3000

    The digital SFM3000 mass flow meter excels in accuracy, fast response time and low pressure drop, making it highly suitable for cost-sensitive flow measurements in medical and industrial applications.

    Your Contact to Sensirion

    Umschlag

    Contact

    Contact our sensor experts:

    Please contact us

    Distributoren

    Distributors & Representatives

    Here you find the nearest distributor and/or representative in your area.

    Learn more

    Support Center

    Please find here an overview of various support topics:

    Go to Support Center

    Standorte

    Locations

    Find out where we are located:

    Our Locations

    Please Find Here Various Support Topics

    Buy Our Products at Your Local Distributor

    About Sensirion

    Environmental Sensors

    Flow Sensors

    Media/Newsroom

    Investors

    Useful Links

    Sensirion Automotive Solutions

    Career

    Support Center

    Partner Access

    General

    Terms and Conditions

    Terms and Conditions for US Customers

    Supplier Social Responsibility

    Quality, Environment and Ethics

    Sensirion AG

    Laubisruetistrasse 50

    8712 Staefa ZH, Switzerland

    Tel. +41 44 306 40 00

    infosensirioncom

    2021 © Sensirion AG Switzerland
    • Home
    • Sitemap
    • Privacy Policy and Cookies
    • Imprint
    • Login
    • Disclaimer