IEC 60704-2-13:2011 pdf – Household and similar electrical appliances -Test code for the determination ofairborne acoustical noise – Part 2-13: Particular requirements for range hoods.
Prior to noise measurements, the range hood shall have been in operation for running in for at least 4 hat the highest speed setting for normal use (see notes in 1.2).
6.1.4
Replacement.
Immediately before each series of noise measurements, the range hood equipped for its intended use is operated for stabilizing at the highest speed setting for normal use (see notes in 1.2) for 10 mm.
6.2 Supply of electrical energy and of water or gas
6.2.3 and 6.2.4 Not applicable
6.4 Loading and operating of appliance during test
6.4.2
Replacement:
The appliances shall be equipped according to 6.1.1.
The range hood shall be operated at the highest speed setting for normal use (see notes in 1.2).
Air-extraction range hoods shall be loaded using a pipe connected to a muffler according to Figure 101. The pipe shall be rigid with smooth inner walls and shall have the widest diameter among those specified by the manufacturer. If not stated, a standard pipe with the best fitting diameter shall be used. The muffler shall have an insertion loss as specified in the table of Figure 101, It shall have a circular section with the same internal diameter as that of the pipe, a length as specified in Figure 101 and shall not have parts protruding inside that may cause additional pressure drops. The pipe and the muffler shall also comply with all the specifications reported in Figure 101 and care shall be taken that they do not radiate noise,
Range hoods with external fan shall be connected to the fan with a pipe and a muffler according to Figure 103. The pipe shall be rigid with smooth inner walls and shall have the widest diameter among those specified by the manufacturer. If not slated, a standard pipe with the best fitting diameter shall be used. The muffler shall be provided with the appliance. If the manufacturer did not provide a muffler, the appliance is tested without muffler.
In particular, when connecting the pipe and muffler system to the range hood, care shall be taken that this connection does not transfer any additional structure borne noise. For this purpose, isolating connecting pieces can be used.
Static forces from the standard exhaust to the range hood shall also be avoided.
NOTE 101 Tb. fastening ot th, rnUfll.f I’ovtd not inhl,nc. the acoustical field in 11w test roo4n: for ex.mptq two wiles could be ti’ed around the muffler and on the ceiling.
Whenever it is possible to choose among two or more exit holes for the pipe connection, the one on the upper side of the range hood, if any, shall be used.
Range hoods designed for connection with more than one pipe at the same time shall be connected accordingly to the number of pipes required.
6.4.3 Not applicable
7.1 Microphone array, measurement surface and RSS location for essentially free- field conditions over reflecting plane(s)
Replacement:
For range hoods not intended to be placed against a wall, including built-in appliances, the measurement surface is a parallelepiped with nine microphone positions, as specified in 7.3.1 of ISO 3744 and In Figure 1 of IEC 60704-1. Additional measurement positions may be required according to 7.3.2 of ISO 3744. The number of microphone positions may also be reduced according to 7.4.2 of ISO 3744.
While defining the reference boa around the appliance, the loading pipe connected to a range hood operating in exhausting mode should not be taken into account.
NOTE 101 The front of the appliance is directed in the direction of the a-axis, The preferred value of the measurement distance dig I m
7.1.2
Replacement.
For range hoods intended to be placed against a wall, including built-in appliances, the measurement surface is a parallelepiped with six microphone positions, as specified in 7.3.1 of ISO 3744 and in Figure 2 of IEC 60704-1. Additional measurement positions may be required according to 7.3.2 of ISO 3744. The number of microphone positions may also be reduced according to 74.2 of ISO 3144.
While defining the reference box around the appliance, the loading pipe connected to a range hood operating in exhausting mode should not be taken into account.
NOTE $01 The a andy axes are located in the vertical reflecting plane, with the x-axii directed vertically upwards and the front of the appliance directed in the direction 0$ tile z-axis, The preferred value of the measurement distance ,j 5 1 m.
7.1.3 to 7.1.6 Not applicable
7.4 Measurements
7.4.1
Addition:
The A-weighted time averaged sound pressure level shall be measured over a period of at
least 30 s.
8 CalculatIon of sound pressure and Sound power levels
This clause of Part 1 is applicable except as follows:
Addition.’
Noise emitted by the housing or by the air outfet of an external fan shall be considered as background noise.