Fixed point anemometer for tunnel

The AIRFLOW MkII is a robust, single point monitor designed to measure air velocity (and temperature when specified) within a tunnel environment.


Proven measurement technique
Proven short path ultrasound measurement technique using time of flight differential
No moving parts, wear items or other components that require routine replacement
Self-contained single component instrument
Temperature measurement
Optional pre-calibrated temperature measurement
Intelligent analyser
Intelligent analyser with a range of industry standard outputs
24 month warranty - optional warranty extensions available

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Using proven, ultrasound time of flight technology ensures the AIRFLOW MkII provides consistent and accurate measurements. The data provided by the AIRFLOW-MkII can be used as part of an air quality management system within a tunnel or other confined spaces including rail and cable tunnels and mining applications.

The AIRFLOW-MkII has no moving parts and no regular service requirements, making it a truly fit and forget monitor. With industry standard SCADA / PLC interface options, such as Current Outputs, Digital Relays and RS485 (Modbus RTU) the AIRFLOW-MkII is a self-contained, intelligent, tunnel airflow monitor.


  • Plug and socket connectors simplify the installation and reduce the amount of wiring required
  • Easy to install with no alignment or interconnection required
  • Provides accurate readings which are unaffected by temperature, pressure or humidity
  • Long service intervals with no drift and low maintenance requirements
  • IP67 rated and designed specifically for use in harsh tunnel environments

Airflow illustration

How works the Airflow MKII?

The AIRFLOW tunnel monitor uses proven ultrasonic transit time technology to deliver a eliable measurement of air speed and direction in tunnels. It is a dual axis monitor that can measure air speeds of up to 60m/s with a resolution of 0.01m/s.

Having been designed specifically for tunnel environment, the AIRFLOW monitor is of rugged construction using powder coated stainless steel and UL rated flame retardant polycarbonate to achieve an IP67 / NEMA 6P protection rating. This instrument can withstand the corrosive atmosphere and regular tunnel washing that the tunnel environment endures.

The AIRFLOW monitor is a self-contained intelligent analyser with on-board industry standard SCADA/PLC interface options, such as 0/2/4-20 mA outputs, alarm relay contacts and a choice of serial communications protocols. As such the AIRFLOW has no need for a control unit although one is available as an option. As a standalone instrument the AIRFLOW is be set-up and controlled using the utility software supplied, installed on a PC or laptop and connected via the USB connector.

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