scope:

Scope of applicability of the code of practice

The term "fans" signifies turbo-machines for the conveyance of gases at a pressure ratio of up to p₂/p₁ = 1.3. This boundary has been selected on the basis of a general agreement, and the option of classifying a machine, the operating data of which are located in the immediate vicinity of this figure, either as a fan or a compressor (see VDI 2045), naturally remains.

The present code of practice for fans is intended to provide generally valid principles for acceptance and performance tests in the field of fans. It comprises a series of specifications which reflect the present-day level of technology and are tailored to conditions such as typically occur. They therefore apply in their full scope.

Where tests based on this code of practice are planned, it must be ensured as early as the design of the system stage that tests in conformity with this code of practice can actually be performed (e.g. stipulation of measuring cross-sections and incorporation of suitable measuring points).

Where no separate agreement to the contrary has been made, the code of practice shall be deemed to be concerned only with the fan itself. It is, however, recommendable to specify in all cases the components which are to be regarded as being constituent components of or appurtenant to the fan.