IEC 61591:2019

IEC 61591 ®
Edition 2.0 2019-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Cooking fume extractors – Methods for measuring performance

Extracteurs de fumée de cuisine – Méthodes de mesure de l'aptitude à
la fonction
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IEC 61591 ®
Edition 2.0 2019-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Cooking fume extractors – Methods for measuring performance

Extracteurs de fumée de cuisine – Méthodes de mesure de l'aptitude à

la fonction
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 97.040.20 ISBN 978-2-8322-7410-1

– 2 – IEC 61591:2019 © IEC 2019
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Classification . 9
5 List of measurements . 9
6 General conditions for measurements . 9
6.1 Test room . 9
6.2 Installation and positioning . 9
6.3 Electricity supply . 10
6.4 Filters . 10
6.5 Fan control . 10
6.6 Instrumentation and measurements . 10
7 Dimensions and mass . 11
7.1 Overall dimensions . 11
7.2 Distance between cooking fume extractor and cooking appliance. 11
7.3 Mass . 12
8 Power measurement of low power modes . 12
9 Airborne acoustical noise . 12
10 Volumetric airflow . 12
10.1 Purpose . 12
10.2 Measuring setup . 12
10.3 Measurement of the volumetric airflow . 14
10.4 Calculation of the fluid dynamic efficiency (FDE ) . 16
hood
11 Effectiveness of the lighting system . 17
11.1 Purpose . 17
11.2 Measurement . 17
11.3 Assessment . 19
12 Odour reduction . 19
12.1 Purpose . 19
12.2 Measuring setup . 19
12.3 Measurement . 21
12.4 Calculation of the odour reduction factor . 21
13 Grease absorption . 22
13.1 Purpose . 22
13.2 Measuring setup . 22
13.3 Preparation . 26
13.3.1 Determining the mass . 26
13.3.2 Warm-up period . 27
13.4 Measurement . 27
13.5 Assessment . 27
Bibliography . 29

Figure 1 – Measurement of airflow . 13

Figure 2 – Example working point of a cooking fume extractor in extraction mode . 15
Figure 3 – Example diagram of the best efficiency point (BEP) . 17
Figure 4 – Measurement points for assessing the effectiveness of the lighting system . 19
Figure 5 – Example of a test room . 20
Figure 6 – Chamber for the grease absorption of a range hood or a microwave hood
combination . 24
Figure 7 – Chamber for the grease absorption of a down-draft system . 25
Figure 8 – Cookware used for measuring the grease absorption . 26

Table 1 – Instruments . 11
Table 2 – Measurements . 11
Table 3 – Relevant measurement points for assessing the effectiveness of the lighting
system . 18

– 4 – IEC 61591:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
COOKING FUME EXTRACTORS –
METHODS FOR MEASURING PERFORMANCE

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61591 has been prepared by subcommittee 59K: Performance of
household and similar electrical cooking appliances, of IEC technical committee 59:
Performance of household and similar electrical appliances.
This second edition cancels and replaces the first edition published in 1997, Amendment 1:2005
and Amendment 2:2010. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) new subclause about instruments and measurements (see 6.6);
b) new procedure for measuring the fluid dynamic efficiency (FDE), which follows the
CENELEC proposal in principle;
c) revised procedure for determining the odour reduction for cooking fume extractors in
recirculation mode (see Clause 12);
d) modification to the measurement of the effectiveness of the lighting system (see Clause 11);
e) clearer procedure to measure the grease absorption (see Clause 13);

The text of this International Standard is based on the following documents:
CDV Report on voting
59K/304/CDV 59K/306/RVC
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
In this standard, the following print types are used:
• terms listed in Clause 3: Arial bold.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 61591:2019 © IEC 2019
COOKING FUME EXTRACTORS –
METHODS FOR MEASURING PERFORMANCE

1 Scope
This document applies to cooking fume extractors incorporating a fan for the recirculation
or extraction mode situated in a household kitchen.
It can also be used for cooking fume extractors where the fan is mounted separately from the
appliance, but controlled by the appliance when the fan is defined in the technical
documentation (e.g. name plate data) and instructions for installation.
This document deals also with down-draft systems arranged beside, behind or under the
cooking appliance.
This document defines the main performance characteristics of these appliances, which are of
interest to the user, and specifies methods for measuring these characteristics.
This document does not specify a classification or ranking for performance.
NOTE This document does not deal with safety requirements that are in accordance with IEC 60335-1 and
IEC 60335-2-31.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60584-1, Thermocouples – Part 1: EMF specifications and tolerances
IEC 60704-2-13, Household and similar electrical appliances – Test code for the determination
of airborne acoustical noise – Part 2-13: Particular requirements for range hoods and other
cooking fume extractors
IEC 62301, Household electrical appliances – Measurement of standby power
ISO 5167-1, Measurement of fluid flow by means of pressure differential devices inserted in
circular cross-section conduits running full – Part 1: General principles and requirements
ISO 5167-2, Measurement of fluid flow by means of pressure differential devices inserted in
circular cross-section conduits running full – Part 2: Orifice plates
ISO 5167-3, Measurement of fluid flow by means of pressure differential devices inserted in
circular cross-section conduits running full – Part 3: Nozzles and Venturi nozzles
ISO 5167-4, Measurement of fluid flow by means of pressure differential devices inserted in
circular cross-section conduits running full – Part 4: Venturi tubes
ISO 80000-1:2009, Quantities and units – Part 1: General

3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
cooking fume extractor
appliance with fan and filter intended to collect and treat cooking fumes, which can be operated
in recirculation mode or extraction mode
3.2
range hood
cooking fume extractor installed over a cooking appliance
3.2.1
wall range hood
range hood mounted to the wall
3.2.2
island range hood
range hood mounted to the ceiling
3.2.3
ceiling range hood
range hood integrated onto or into the ceiling
3.2.4
built-in range hood
range hood mounted onto or into a cabinet
3.3
microwave hood combination
cooking fume extractor integrated in a microwave oven
3.4
multiple combination hood
cooking fume extractor where the fan is mounted separately of the appliance, but controlled by
the appliance
3.5
down-draft system
cooking fume extractor intended for installation adjacent to a cooking appliance or integrated
in a cooking appliance that draws vapour down into a duct
Note 1 to entry: A down-draft system can also be a system where the fan is mounted separately from the appliance
but controlled by the appliance.
3.6
recirculation mode
mode of a cooking fume extractor that discharges air back into the room, which includes an
odour-reduction filter
– 8 – IEC 61591:2019 © IEC 2019
3.7
extraction mode
mode of a cooking fume extractor that discharges the air to the outside of the building by
means of ducting
Note 1 to entry: Extraction mode is also known as "vented mode" or "ducted mode".
3.8
rated voltage
voltage assigned to the cooking fume extractor by the manufacturer
3.9
grease absorption factor
G
FE
percentage of grease retained within a grease filter
3.10
grease filter
components for absorbing grease, which are intended to be replaced or removed for cleaning
without tools
3.11
odour-reduction filter
components for reducing odour
3.12
odour reduction factor
capability of the cooking fume extractor to reduce odours
3.13
odour dispersion time
time taken to reduce odours to a defined level after the odour generating source has been
switched off
3.14
highest continuous setting for normal use
control setting of cooking fume extractor at highest speed, excluding the boost position
setting
Note 1 to entry: Marked setting on the appliance, which is described in the instructions for use.
3.15
boost position setting
marked control setting at maximum fan speed, which is automatically limited in duration
Note 1 to entry: Marked setting on the appliance, which is described in the instructions for use.
3.16
working point
intersection point of pressure/airflow curve and resistance curve
3.17
best efficiency point
BEP
maximum value of the efficiency of a cooking fume extractor
Note 1 to entry: This term applies to the French language only.

3.18
lighting system
devices used for the illumination of the cooking surface, excluding ambient illumination, unless
there is only one control switch
Note 1 to entry: Power supply units and controllers are included.
3.19
illumination E
middle
average illumination of the lighting system on the cooking surface measured in lux under
standard conditions
4 Classification
According to the mode:
– recirculation mode;
– extraction mode.
A cooking fume extractor may be constructed to incorporate both modes.
5 List of measurements
Performance is determined by assessing the following:
– overall dimensions;
– mass;
– power measurement of low-power modes;
– airborne acoustical noise;
– volumetric airflow;
– effectiveness and electric power input of the lighting system;
– ability to reduce odours;
– ability to absorb grease.
6 General conditions for measurements
6.1 Test room
The tests are carried out in a draught-free room. The ambient temperature of the room is
maintained at (23 ± 2) °C. The absolute air pressure shall be between 913 hPa and 1 063 hPa.
6.2 Installation and positioning
The appliance has to be clean and free of any residues of packaging material and protective
foil. All tests have to be carried out following the order of the clauses of this document with one
and the same appliance.
The cooking fume extractor (except for the down-draft system) is installed above a cooking
appliance with the distance of (600 ± 10) mm. The distance is determined between the lowest
level of the cooking fume extractor and the highest level of the cooking appliance. The cooking
fume extractor is installed and operated in accordance with the manufacturer’s instructions
(except for the distance above the cooking appliance).

– 10 – IEC 61591:2019 © IEC 2019
Any extendible visor, which is extendable for normal use in accordance with the manufacturer’s
instructions, shall be opened accordingly. If no instructions are given, the extendible visor is
fully opened.
If the down-draft system can be elevated, the manufacturer’s instructions are followed;
otherwise, it shall be measured in its maximum elevated position for use.
The maximum sized duct in accordance with the manfacturer’s instructions is to be used.
For all tests, the appliance is operated with unchanged default factory settings (e.g. brightness
of the display or changeable light colour). Supplementary parts that are part of the appliance
are mounted in accordance with the manufacturer’s instructions. Ensure that no network is
connected to the appliance for the duration of the measurement, except for the remote control.
Before the measurement is made, any conditioning of the cooking fume extractor, unless
explicitly required in this document, is not allowed.
Ensure that any automatic modes, where the fan speed is altered, are switched off.
6.3 Electricity supply
The cooking fume extractor is supplied at the rated voltage ±1 %.
If the appliance has a rated voltage range, the tests are carried out at the nominal voltage of
the country where the appliance is intended to be used.
The supply frequency shall be at the rated frequency ±1 % throughout the test. If a frequency
range is indicated, then the test frequency shall be that of the nominal frequency of the country
in which the appliance is intended to be used.
6.4 Filters
For all tests, it shall be ensured that all filters are positioned correctly.
For appliances with more than one grease filter, the filters shall be positioned with no gap in
between (centrally positioned).
6.5 Fan control
Cooking fume extractors shall be tested in the highest continuous setting for normal use,
as stated in the manufacturer’s instructions.
6.6 Instrumentation and measurements
Instruments used and measurements made for this document shall comply with the
specifications in Table 1 and Table 2. The accuracy is applied to the measured value.

Table 1 – Instruments
Parameter Unit Minimum Accuracy Additional
resolution requirements
Mass g 0,1 g ±0,5 g
Temperature °C 0,1 °C ±1,5 K Thermocouple type J
or K in accordance
with
IEC 60584-1
or
PT100 sensor in
accordance with
IEC 60751.
Time s 1 s ±1 s
Power W - ±1 %
Illuminance lx ±10 % Value under
consideration –
International standard
about illuminance
classification is
pending.
Pressure/Air pressure Pa ±1 % The accuracy is for
pressures ≤ 150 Pa at
least 1,5 Pa.
Table 2 – Measurements
Parameter Unit Minimum Accuracy Additional
resolution requirements
Voltage V - ±0,5 % -
Volumetric airflow ±2 %
m /h
In accordance with
Power measurement - -
IEC 62301
If numbers have to be rounded, they shall be rounded to the nearest number in accordance with
ISO 80000-1:2009, B.3, Rule B. If the rounding takes place to the right of the comma, the
omitted places shall not be filled with zeros.
7 Dimensions and mass
7.1 Overall dimensions
The overall dimensions of the cooking fume extractor are measured. The longest width, depth
and height, including any control knobs or other projections, are stated in millimetres rounded
to 10 mm. If dimensions are variable while the cooking fume extractor is operated in normal
use, then the minimum and maximum sizes are stated.
For cooking fume extractors with extraction mode, the dimensions of the air-outlet orifice
are measured and stated.
7.2 Distance between cooking fume extractor and cooking appliance
The shortest distance between the lowest level of the cooking fume extractor, except down-
draft systems, and the highest level of the cooking appliance is measured and indicated in
millimetres, rounded to 10 mm.

– 12 – IEC 61591:2019 © IEC 2019
7.3 Mass
The mass of the cooking fume extractor, including any filters, supply cord and plug, is
measured and stated in kilograms, rounded to one decimal place.
8 Power measurement of low power modes
The power of low-power modes are measured in accordance with IEC 62301.
9 Airborne acoustical noise
Where an airborne acoustical noise measurement is required, it shall be measured in
accordance with IEC 60704-2-13.
NOTE A possible procedure for the statistical determination of declared noise values is described in IEC 60704-3.
10 Volumetric airflow
10.1 Purpose
The purpose of this test is to determine the volumetric airflow in general (see 10.3) and at the
best efficiency point (BEP) (see 10.4).
The airflow is measured in accordance with the methods contained in ISO 5167-1, ISO 5167-2,
ISO 5167-3 and ISO 5167-4.
10.2 Measuring setup
The maximum possible air-outlet of the cooking fume extractor is connected to a pressure
compensation chamber (see Figure 1). The duct diameter needs to be the same as that of the
air-outlet.
A cooking fume extractor without ducting, e.g. a cooking fume extractor with recirculation
mode, is connected directly to the pressure compensation chamber as shown in Figure 1b).
The pressure compensation chamber shall be adapted to the dimensions of the cooking fume
extractor under test.
a) Setup for cooking fume extractor with duct

b) Setup for cooking fume extractor without duct

c) Multiple combination hood or down-draft system with fan for indoor use

d) Multiple combination hood or down-draft system with fan for outdoor use
Key
a 5 times the diameter of the duct, which shall be 4 auxiliary fan
sealed
1 cooking fume extractor 5 baffle
2 pressure compensation chamber 6 static pressure gauge
3 pressure differential device for airflow 7 separately mounted fan
measurment
Figure 1 – Measurement of airflow

– 14 – IEC 61591:2019 © IEC 2019
Follow the manufacturer’s instructions regarding the distance between points 1 and 7, as shown
in Figure 1c) and 1d). If there is no value for the distance given, then the distance a is used.
A cooking fume extractor in recirculation mode can have different geometries as "air outlet
areas". These have to be adapted to the pressure compensation chamber.
For non-circular ducts, a virtual diameter is considered that represents the same cross-section.
The grease filter is installed for the test.
The odour-reduction filter is not installed for the test, except if the test is done in recirculation
mode.
10.3 Measurement of the volumetric airflow
The cooking fume extractor is operated at the highest continuous setting for normal use
for at least 1 800 s for warming up.
The cooking fume extractor is operated and, by suitably adjusting the auxiliary fan or the
baffle, the airflow corresponding to various pressures can be determined.
The measurements are made with the controls positioned at the highest continuous setting
for normal use, at the lowest setting, and at the boost position setting, if any.
The airflow in recirculation mode is determined when the static pressure in the compensation
chamber is at ambient pressure. For the measurement of the grease absorption in recirculation
mode in Clause 13, the pressure drop of the odour-reduction filter has to be determined.
The airflow in extraction mode is determined for discharge into a flue, which has the following
pressure drop depending on the diameter of the air-outlet when there is an airflow of 200 m /h:
< 100 mm:     30 Pa b = 0,000 75
120 mm to 125 mm: 15 Pa b = 0,000 375
150 mm to 160 mm: 5 Pa b = 0,000 125
200 mm to 250 mm: 2,5 Pa b = 0,000 062 5
>250 mm: 1,25 Pa b = 0,000 031 25
For determining the theoretical resistance curve for a flue pipe, the following formula is used:
y = b ∙ x
where
y is the numerical value of the pressure, expressed in Pa;
b is a value depending on the dimensions of the air-outlet;
x is the numerical value of the airflow, expressed in m /h.
NOTE A pressure/airflow curve is determined for the appliance.
Figure 2 shows a reference resistance curve and a characteristic curve of a cooking fume
extractor.
Key
reference resistance curve of an exhaust duct with an inner diameter of 150 mm
example characteristic curve of a cooking fume extractor
working point (intersection of the duct pressure drop and the characteristic curve of the cooking fume
extractor)
Figure 2 – Example working point of a cooking fume extractor in extraction mode
The airflow is stated for the working point at the highest continuous setting for normal use,
at the lowest setting, and at the boost position setting, if any.
The working point is calculated to a reference density of 1,2 kg/m .
ρ
Ref
ΔΔpp=
CFE s
ρ
Cha
where:
is the reference pressure difference cooking fume extractor, in Pa;
Δp
CFE
is the pressure difference in the chamber at test conditions, in Pa;
Δp
s
ρ is the reference air density of 1,2 kg/m ;
Ref
ρ is the air density in the chamber at test conditions, in kg/m .
Cha
Alternative working points corresponding to other pressure drops may be specified instead, in
which case the pressure drop has to be stated in the report.

– 16 – IEC 61591:2019 © IEC 2019
10.4 Calculation of the fluid dynamic efficiency (FDE )
hood
The calculation of the fluid dynamic efficiency (FDE ) is only possible for a cooking fume
hood
extractor in extraction mode.
For determining the fluid dynamic efficiency (FDE ) in accordance with 10.4, a pressure-
hood
airflow curve and the corresponding electric-power curve with a minimum of 25 measuring
points over the whole range are determined (see Figure 3).
th
For the calculation, use the 6 degree polynomial and at least 10 measuring points, which are
the interval 75 % to 125 % of the volume flow value at maximum energy efficiency. The
measuring points should be well distributed over the range, whereby at least 5 measuring points
of the volume flow has to be lower, and at a further 5 measuring points, the volume flow has to
be higher than the volume flow of the calculated best effiency point (BEP). The BEP is the
maximum value of this regression curve.
For the calculation of FDE , the measured data for the boost position setting is taken into
hood
account. If no boost position setting is available, then the highest continuous setting for
normal use is taken into account.
The BEP is determined.
The fluid dynamic efficiency (FDE ) at the BEP (see Figure 3) is calculated with the following
hood
formula, and is rounded to one decimal place:
Qp⋅Δ
BEP BEP
FDE ×100
hood
3 600⋅ P
BEP
where:
is the numerical value of the airflow at the best efficiency point, expressed in m /h and
Q
BEP
rounded to the first decimal place;
Δp is the numerical value of the difference static pressure at the best efficiency point,
BEP
expressed in Pa and rounded to the nearest integer;
P is the numerical value of the electric power consumption at the best efficiency point,
BEP
expressed in W and rounded to the first decimal place.
The values in the formula are not calculated in relation to the reference air density.

=
Key
– ∙∙ –

resistance curve of an exhaust duct Working point


pressure at BEP electric power at BEP
– ∙ – –––––
electric power curve FDE curve

BEP pressure/airflow curve
Figure 3 – Example diagram of the best efficiency point (BEP)
11 Effectiveness of the lighting system
11.1 Purpose
This method is used to assess the effectiveness of the lighting system of cooking fume
extractors.
11.2 Measurement
The lighting system of the cooking fume extractor is operated for at least 1 800 s for
warming up.
The test is carried out in a room in which all other light sources are extinguished. During the
test, only the lighting system of the cooking fume extractor is on.
The electric power input of the lighting system (P ) is determined by measuring the electric
L
power input of the whole cooking fume extractor while only the lighting system is turned on.
P is stated in W and rounded to the first decimal place.
L
NOTE P includes losses at the transformer or other electronic components.
L
– 18 – IEC 61591:2019 © IEC 2019
To avoid reflections, all adjacent surfaces, including the backwall and the cooking appliance,
are covered, extended by at least 500 mm on both the left-hand and right-hand sides of the
measurement area with a sheet of matt-black painted plywood or similar board.
The distance as determined in 6.2 is the distance between the cooking fume extractor
mounted and the aperture of the illuminance measurement device.
The number and positioning of the measurement points is defined in Table 3 according to the
width W of the cooking fume extractor. The maximum width according to 7.1 applies. The
positions of the measurement points are determined in Figure 4, whereby the measurement
points 1, 2 and 3 show the centre line of the cooking fume extractor.
Table 3 – Relevant measurement points for assessing the effectiveness
of the lighting system
Width (W) of cooking fume extractor (see 7.1) Relevant measurement points
in mm (see Figure 4)
W < 800 1 to 9
800 ≤ W < 1 050 1 to 15
1 050 ≤ W < 1 300 1 to 21
1 to 27
W ≥ 1 300
The centre of island and ceiling range hoods has to be in line with measurement point 2 (see
Figure 4).
Wall range hoods, built-in range hoods and microwave hood combinations are mounted
on the wall of the test room. The baseline of the measurement panel in Figure 4 is aligned to
the wall of the test room.
The illuminance for each measurement point is stated in lux and rounded to the nearest integer.

Dimensions in mm.
Key
C centre line defined by the measurement points 1, 2 and 3
b baseline
measurement points
Figure 4 – Measurement points for assessing the effectiveness of the lighting system
11.3 Assessment
The arithmetic average of the measurement points under test is calculated, and this value is
stated as the illumination E in lux, rounded to the nearest integer.
middle
12 Odour reduction
12.1 Purpose
This method is used to assess the effectiveness of odour-reduction filter(s) of cooking fume
extractors operated in recirculation mode.
NOTE The method is not used for cooking fume extractors operated in extraction mode because odour-reduction
filters are not used in extraction mode.
12.2 Measuring setup
The test is carried out in a sealed room having a volume of (22 ± 2) m , the walls of which are
impervious to methyl ethyl ketone (MEK). The response time of the system is measured by
placing an easily detectable amount of MEK directly at the entrance of a sampling point and
measuring the time until it is detected. The response time is added to all measurements where
the information arrives delayed by this time.
An electric hob is installed along one of the longer walls of the room together with kitchen
cabinets. The kitchen cabinets and wall cabinets, shall be sealed from the rest of the air in the
test room. The room is considered to be adequately sealed if the concentration of MEK in the
room drops by less than 5 %, sixty minutes after the solution has been distributed.

– 20 – IEC 61591:2019 © IEC 2019
Cooking fume extractors, except the down-draft systems, are installed centrally above the
electric hob, at a height of (600 ± 10) mm. On both sides, wall cabinets are mounted.
Island range hoods and ceiling range hoods are installed also at a height of (600 ± 10) mm
above the electric hob, but not centrally. They are installed with a distance to the wall of
(200 ± 5) mm. Wall cabinets on both sides are not mounted.
Down-draft systems have to be installed in accordance with the manufacturer’s instructions.
Wall cabinets are not mounted.
The room and the kitchen furniture, together with the layout, are shown in Figure 5
Dimensions in millimetres
Figure 5 – Example of a test room
NOTE 1 When handling MEK, normal precautions have to be taken.
The characteristics of the test room are established without the cooking fume extractor being
operated. The same cookware as specified in Clause 13 is placed on the front left-hand cooking
zone, matching the size of the cooking zone as well as possible. However, it may vary by a
maximum of ±20 mm. If a electric hob element is used, the height of the hob element and the
cookware shall not exceed 205 mm.
Following the description in Clause 13, a thermocouple is mounted on the cookware.
The temperature in the bottom of the cookware shall be maintained at (170 ± 10) °C.

A solution containing (12 ± 0,1) g of methyl ethyl ketone (MEK) in (300 ± 1) g of demineralised
water is continually dripped onto the cookware at such a rate that all the solution has been used
after (1 800 ± 10) s plus response time. The solution is evenly dispersed throughout the room
by means of a fan. The concentration of MEK in the room C is measured (1800 ± 10) s after
the dripping started. For this, the concentration of MEK is detected using four sampling points
each separated by (500 ± 10) mm vertically, as shown in Figure 5. The detection equipment for
measuring the MEK concentration is located outside the room. PTFE tubes with an inner
diameter of (2,0 ± 0,2) mm of equal length and connected to each other are suitable to link the
sampling points to the measuring equipment.
NOTE 2 Flame ionization equipment is suitable for measuring the concentration of MEK.
The room is ventilated until the concentration of MEK is less than 1 % of C .
The cooking fume extractor is operated at the highest continuous setting for normal use for
at least 1 800 s for warming up.
The odour-reduction filter(s) are conditioned by heating at (50 ± 5) °C for at least 16 h. Then
they are mounted into the warmed up cooking fume extractor.
12.3 Measurement
The cooking fume extractor is operated with any fan control adjusted to the highest
continuous setting for normal use immediately after warming up. The MEK solution is dripped
into the heated cookware so that (312 ± 1,5) g has been evaporated within (1 800 ± 10) s. The
concentration of MEK C in the room is measured (1 800 ± 10) s plus response time after the
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