It is easy to install and maintain because of lightweight and compact, and has no moving parts. For operation in areas where frequent extreme icing conditions will be encountered, built-in, thermostatically controlled heaters are available. YDH AWS-1 Ultrasonic anemometers are provided with a built-in, flux-gate compass, which automatically references the wind direction output to magnetic north, regardless of the sensors orientation. This compass feature, combined with our sensors small size, low weight and low power requirements makes it very easy to transport and deploy for short-term studies. These features also make it the ideal sensor for providing meteorological data input to a computer that performs real time dispersion calculations at an accidental spill or release of hazardous materials. YDH AWS-1 Ultrasonic anemometer measures the wind using the principles described above without any moving mechanical devices, i.e. there are no physical constraints on the sensor response due to mechanical friction, aerodynamic drag, lift or transducer mass. YDH AWS-1 Ultrasonic anemometer is an instrument that exhibits an instantaneous response, has zero threshold, no delay distance and is critically damped. The accuracy of the wind speed measurement is the same as the resolution (0.1 m/s) and is only limited by the electronics of the sensor.