SENSIRON SFM3 Series Gas Flow Sensors

Product Information

Specifications:

• Form Factor: Medical cones 22mm (ISO5356)
• Sensor: Various models as listed below
• Measured Gases: Air, O2, HeliOx
• Flow Range: Varies based on model
• Pressure Drop @ Flow: Varies based on model
• Typical Accuracy: Varies based on model
• Recommended Supply Voltage: Varies based on model (typically 3.3V or 5V)

Product Usage Instructions

• Inspiratory Flow Sensors:
  If you identify more than one sensor option, evaluate the sensor(s) in your device as the specific device design can influence the measurement.
• Proximal Flow Sensors:
  Gage pressure describes the pressure difference between the gas pressure in the tubes/flow sensor and the ambient pressure.
• Expiratory Flow Sensors:
  The SFM3200-AW is designed for the expiratory position with features like minimized pressure drop, washability, a heater, and the capability to measure vapor-saturated gas/air.
• Note: Inspiratory sensors are not designed to be cleaned or disinfected and require non-condensing operating conditions.

FAQ:

• Q: How do I select the right flow sensor for my medical ventilation or high flow device?
  A: Refer to the figure provided in the manual that categorizes sensors based on their position in the ventilation system. Consider unique features and characteristics of sensors as well.
• Q: Can Inspiratory sensors be disinfected?
  A: No, Inspiratory sensors are not designed to be cleaned or disinfected.

Selection guide for Sensirion gas flow sensors

Finding the right flow sensor (SFM) for your medical ventilation or high flow device.
Our flow sensor portfolio offers a comprehensive range of gas flow sensors optimized for medical applications. The SFM product range is specifically engineered for medical ventilation, addresses all relevant flow monitoring requirements and is organized in three families, depending on the position of the sensor in the ventilation system:

1. Inspiratory
2. Expiratory
3. Proximal

The figure below provides a first guideline to select a suitable sensor depending on the beforementioned position in the application.

In addition, some sensors offer unique features and characteristics that may be considered during sensor selection. These features are summarized in the following while the table on page 4-6 provides a  comprehensive overview.

 Inspiratory flow sensors

Our inspiratory flow sensors are typically used inside the ventilator to measure the individual air/O2/heliox gas lines as well as the total flow of the mixed gas before delivery to the patient.

• Selection based on operating gage pressure1
  • 1bar → SFM4300 (or SFM4200 for flows > 50slm)
  •  150mbar → SFM3013
• Lower operating pressure: all other sensors (SFM3003 family, SFM3100, SFM3119 and SFM3200).
• Consider the following criteria according to your requirements to identify the most suitable sensor in the table on page 4:
• Form factor and size
• Mechanical connection
• Measured gases
• Flow range and range of best performance (low or high flows)
• Analog or digital output
• Special features like gas NTC temperature sensor etc.

If you identify more than one sensor option, it is recommended to evaluate the sensor(s) in your device as the specific device design can influence the measurement.

Proximal flow sensors

Gas flow sensors specifically designed to monitor flow in close proximity to the patient, where the following main challenges have been resolved by our portfolio:

• High humidity and condensation
  All our proximal sensors are capable to measure saturated gas/air and feature a heater to prevent condensation at the sensor’s chip, therefore ensuring continued accuracy.
• Contamination
  We offer both single-use and washable sensors.
• Sensor handling by medical personnel
  All our proximal sensors feature a mechanical interface allowing a clip-on connection, easy to disconnect and reconnect.
• Inspiration and expiration flow
  All our proximal sensors allow bi-directional flow sensing.
• Individual sensor packaging for single-use sensors
  Individual sensors are protected against contamination from their production until their use by caregivers. Quality control is improved, supply chain management is simplified, and a customized label  brings all needed information to the users.

The selection of the right sensor is based on two main criteria 

• Patient group: neonates or adults/pediatric
• Use in clinical setting: single use/disposable or washable

Gage pressure describes the pressure difference between the gas pressure in the tubes / flow sensor and the ambient pressure

Expiratory flow sensors

SFM3200-AW has been specifically designed for the expiratory position with a minimized pressure drop, washability, a heater and the capability to measure vapor-saturated gas/air.

Alternative options

• Proximal sensors can be used further from the patient in expiratory position, in case a disposable option is preferred.
• Inspiratory sensors can be placed in the expiratory position if measures are taken against contamination (like HMF filters) and condensation (water traps). Inspiratory sensors are not designed to be cleaned or disinfected and require non-condensing operating conditions.

Form factor	Sensor	Measured gases	Flow range [slm]	Pressure drop @flow[slm]	Typ. accuracy [%m.v.] @flow[slm]	Recommended supply voltage (allowed)	Special features
Inspiratory flow sensors
Medical cones 22mm (ISO5356)	SFM3003-CL		-30 to +300	@60: 80Pa @200: 500Pa	@200: ±2%	3.3V (2.7 – 5.5V)	Low pressure drop
This form factor usually gives better accuracy at	SFM3003-CE		–150 to +300	@60: 100Pa @200: 600Pa	@200: ±2.5%	3.3V (2.7 – 5.5V)	Extended negative flow range
higher flows	SFM3003-CET		–150 to +300	@60: 100Pa @200: 600Pa	@200: ±2.5%	3.3V (2.7 – 5.5V)	Extended negative flow range NTC temperature sensor in gas path
		Air O2 Air/O2 mixtures
	SFM3013-CL		-30 to +300	@60: 80Pa @200: 500Pa	@200: ±2%	3.3V (2.7 – 5.5V)	Low pressure drop Higher pressure resistance up to 1bar gauge
	SFM3013-CLM		Air/O2: -30 to +300 HeliOx: -30 to +200	@60: 80Pa @200: 500Pa	@200: ±2% Heliox: ±4.5%	3.3V (2.7 – 5.5V)	Higher pressure resistance up to 1bar gauge Additional HeliOx calibration
	SFM3019		-10 to +240	@60: 80Pa @200: 500Pa	@200: ±2%	3.3V (2.7 – 5.5V)	See successor SFM3003-300-CL
	SFM3020	Air O2 Air/O2 mixtures formula provided	-10 to +160	@60: 80Pa @200: 500Pa	@160: ±2%	5V	Analog output 0.5 – 4.5V
	SFM3200	Air O2 Air/O2 mixtures formula provided	-100 to +250	@60: 100Pa @200: 750Pa	@100: ±3%	5V	See successor SFM3003-CL or CE

 

Form factor	Sensor	Measured gases	Flow range [slm]	Pressure drop @flow[slm]	Typ. accuracy [%m.v.] @flow[slm]	Recommended supply voltage (allowed)	Special features
Compact	SFM3100-VC	Air O2 Air/O2 mixtures formula provided	-24 to +240	@60: 300Pa	@60: 2.5%	5V	NTC temperature sensor in gas path
This form factor usually gives better accuracy at				@200: 1600Pa		(4.75 – 5.25V)	Analog output 0.095 – 2.45V See successor SFM3119 (digital)
low flows/smaller offset
	SFM3119	Air	-10 to +240	@60: 200Pa	@100: 2%	3.3V	Digital output
		O2		@200: 1600Pa		(2.7 – 5.5V)
		Air/ O2 mixtures
	SFM4200	Air O2 Air/O2 mixtures formula provided	0 to 160	@60: 2000Pa @160: 9000Pa	@80: 2.5%	5V	Air, O2 Down-mount only Operating pressures up to 8 bar
O-ring / Push-in Legris / Down-mount
	SFM4300	Air	0 to 20	@20: 2500Pa	@20: 2%	3.3V	Air, O2, CO2, N2O and mixtures up to 20slm Air, O2 and mixtures up to 50slm High resolution 0.4sccm for 20slm ranges Operating pressures up to 7 bar
		O2	0 to 50	@50: 10000Pa	@50: 4%	(3.0 – 5.5V)
		CO2
		N2O
		Mixtures

Form factor	Sensor	Measured gases	Flow range [slm]	Pressure drop @flow[slm]	Typ. accuracy [%m.v.] @flow[slm]	Recommended supply voltage (allowed)	Special features
Expiratory flow sensors
Medical cones 22mm (ISO5356-1)	SFM3200-AW	·    Air ·    O2 ·    Air/ O2 mixtures formula provided	-100 to +250	@60: 100Pa @200: 750Pa	@100: 3%	5V	·    Bidirectional ·    Autoclavable & cleanable ·    Integrated heater to prevent condensation
Proximal flow sensors
	SFM3300-D	Air O2 Air/ O2 mixtures formula provided	-250 to +250	@60: 180Pa @200: 1400Pa	@100: 3%	5V	See successor SFM3304-D for OEM projects Suitable for adults and children Single-use Integrated heater to prevent condensation Available in catalog distribution
Medical cones 22mm (ISO5356-1) 15mm (ISO5356-1)
	SFM3300-AW	Air O2 Air/ O2 mixtures formula provided	-250 to +250	@60: 180Pa @200: 1400Pa	@100: 3%	5V	Suitable for adults and children Autoclavable & cleanable Integrated heater to prevent condensation
	SFM3304-D	Air O2 Air/ O2 mixtures formula provided	-250 to +250	@60: 100Pa @200: 1150Pa	@100: 3%	3.3V (3.15 – 3.45V)	Improved independence to inlet conditions Suitable for adults and children Single-use Integrated heater to prevent condensation Includes individual sensor packaging ·    Only available for OEM projects
	SFM3400-D	Air O2 Air/ O2 mixtures formula provided	-33 to + 33	@5: 100Pa @25: 900Pa	@33: 3%	5V	Suitable for neonates Single-use Integrated heater to prevent condensation
	SFM3400-AW	Air O2 Air/ O2 mixtures formula provided	-33 to + 33	@5: 100Pa @25: 900Pa	@33: 3%		Suitable for neonates Autoclavable & cleanable Integrated heater to prevent condensation
						5V

Revision history 

Date	Version	Pages	Changes
July 2024	1.0	all	First version

© Copyright Sensirion AG

Documents / Resources

SENSIRON SFM3 Series Gas Flow Sensors [pdf] Owner's Manual SFM3003-CL, SFM3003-CE, SFM3003-CET, SFM3013-CL, SFM3013-CLM, SFM3019, SFM3020, SFM3200, SFM3 Series Gas Flow Sensors, SFM3 Series, Gas Flow Sensors, Flow Sensors, Sensors

References

• User Manual