Measurement of gas flow by means of critical flow Venturi nozzlesBS EN ISO 9300 specifies the geometry and method of use (installation in a system and operating conditions) of critical flow Venturi nozzles (CFVN) used to determine the mass flow rate of a gas flowing through a system. It also gives the information necessary for calculating the flow rate and its associated uncertainty. It applies to Venturi nozzles in which the gas flow accelerates to the critical velocity at the throat (this being equal to the local

2 Pre-conditioning of test specimens

Additional background information

What is BS EN 55011:2009+A1:2010

d)      Contractual documents

both in the detection and analysis of ionizing radiation and for other applications

watertightness and wind resistance for external windows and doors

A/C Manufacturers

BS EN 80601-2-59:2009 Medical electrical equipment

As the requirements are integrated and built on each other

The document has been published as a DD so that its development as a British Standard can benefit from a period of trial and consultation

for as long as it is required

and of planting trees close to existing structures