METHOD AND APPARATUS FOR DETERMINING FLOW

摘要

The present invention relates to the field of pollution monitoring equipment and in particular to aspirated particle detector systems, which detect particles in air sampled from a number of locations. The present invention provides a method and apparatus for determining flow in an aspirated particle detector system, said system comprising a plurality of carriers in fluid communication with a particle detector, comprising means for detecting the flow rate in at least one of the carriers comprising sensing a signal transmitted between a first and a second signal transceiver (44a - d, 42) wherein the first transceiver (42) is adapted to transceive signals in at least two of the carriers. In a preferred embodiment, the invention relates to the use of an ultrasonic means of flow sensing within an aspirated smoke detector system.