IEC 60704-2-13-2011 pdf free download – Household and similar electrical appliances – Test code for the determination of airborne acoustical noise – Part 2-13: Particular requirements for range hoods.
4Measurement methods and acoustical environmentsThis clause of Part 1 is applicable except as follows:
4.2Direct method
Addition:
NOTE 101 lf pure tone components are present in the noise emitted by the source，the estimated standarddeviation of the measured sound pressure levels in the special reverberation room may increase. In such casesadditional microphone positions or source positions may be necessary as specified in ISo 3743-2.
4.3comparison method
Addition:
NOTE 101 lf pure tone components are present in the noise emitted by the source，the estimated standarddeviation of the measured sound pressure levels in the hard-walled test room or in the special reverberation roommay increase. In such cases additional microphone positions or source positions may be necessary as specified inIso 3743-1 or lso 3743-2.
5 Instrumentation
This clause of Part 1 is applicable except as follows:
5.1 lnstrumentation for measuring acoustical dataAddition:
Windscreens should be used if necessary and then corrections for change in the microphonesensitivity shall be added to the observed sound pressure levels.
6 operation and location of appliance under test
This clause of Part 1 is applicable except as follows:
6.1 Equipping and pre-conditioning of appliance6.1.1
Addition:
Recirculation-air range hoods should be fitted with a clean filter(s).
Air-extraction range hoods shall be fitted with the pipe coupling ring, if any, having the largestdiameter among those provided by the manufacturer. if the range hood is designed toaccommodate additional filters, those filters shall be clean and appropriately fitted.
6.1.3
Replacement:
Prior to noise measurements, the range hood shall have been in operation for running in for atleast 4 h at the highest speed setting for normal use (see notes in 1.2).
6.1.4
Replacement:
lmmediately before each series of noise measurements，the range hood equipped for itsintended use is operated for stabilizing at the highest speed setting for normal use (see notesin 1.2) for 10 min.
6.2supply of electrical energy and of water or gas6.2.3 and 6.2.4
Not applicable
6.4 Loading and operating of appliance during test6.4.2
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 notesin 1.2).
Air-extraction range hoods shall be loaded using a pipe connected to a muffler according toFigure 101.The pipe shall be rigid with smooth inner walls and shall have the widest diameteramong those specified by the manufacturer. If not stated, a standard pipe with the best fittingdiameter shall be used.The muffler shall have an insertion loss as specified in the table ofFigure 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 causeadditional pressure drops. The pipe and the muffler shall also comply with ‘all thespecifications 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 muffleraccording to Figure 103. The pipe shall be rigid with smooth inner walls and shall have thewidest diameter among those specified by the manufacturer. lf not stated, a standard pipewith the best fitting diameter shall be used.The muffler shall be provided with the appliance.lf the manufacturer did not provide a muffler, the appliance is tested without muffler.
ln particular，when connecting the pipe and muffler system to the range hood,care shall betaken that this connection does not transfer any additional structure borne noise. For thispurpose, isolating connecting pieces can be used.
Static forces from the standard exhaust to the range hood shall also be avoided.IEC 60704-2-13 pdf download.