oSIST prEN ISO 19424:2025

SLOVENSKI STANDARD
01-oktober-2025
Hladilne omare za živila - Toplotna in energijska učinkovitost, ocene, okoljski
preskusni pogoji in povezane preskusne metode (ISO/DIS 19424:2025)
Refrigerated food lockers - Thermal and energy performance, ratings, environmental test
conditions and associated testing methods (ISO/DIS 19424:2025)
Schließfächer mit Kühlfunktion für Lebensmittel - Thermische und energetische Leistung,
Bewertungen, Umgebungsprüfbedingungen und zugehörige Prüfverfahren (ISO/DIS
19424:2025)
Casiers réfrigérés pour aliments - Performance thermique et énergétique, évaluation,
conditions d’essai environnementales et méthodes d’essai associées (ISO/DIS
19424:2025)
Ta slovenski standard je istoveten z: prEN ISO 19424
ICS:
97.040.30 Hladilni aparati za dom Domestic refrigerating
appliances
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 19424
ISO/TC 86/SC 7
Refrigerated food lockers —
Secretariat: UNI
Thermal and energy performance,
Voting begins on:
ratings, environmental test
2025-06-18
conditions and associated testing
Voting terminates on:
methods
2025-09-10
Casiers réfrigérés pour aliments — Performance thermique et
énergétique, évaluation, conditions d’essai environnementales et
méthodes d’essai associées
ICS: 97.040.30
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 19424:2025(en)
DRAFT
ISO/DIS 19424:2025(en)
International
Standard
ISO/DIS 19424
ISO/TC 86/SC 7
Refrigerated food lockers — Thermal
Secretariat: UNI
and energy performance, ratings,
Voting begins on:
environmental test conditions and
associated testing methods
Voting terminates on:
Casiers réfrigérés pour aliments — Performance thermique et
énergétique, évaluation, conditions d’essai environnementales et
méthodes d’essai associées
ICS: 97.040.30
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
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BE CONSIDERED IN THE LIGHT OF THEIR
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Published in Switzerland Reference number
ISO/DIS 19424:2025(en)
ii
ISO/DIS 19424:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 3
4.1 General .3
4.2 Construction .3
4.3 Operating characteristics .4
4.3.1 Classification according to temperature storage .4
4.3.2 Classification according to environmental condition .4
5 Tests . 4
5.1 General .4
5.2 Tests outside or inside test room .5
5.2.1 Seal test for doors .5
5.2.2 Linear dimensions, areas .5
5.3 Tests inside test room .5
5.3.1 General .5
5.3.2 Test room conditions .6
5.3.3 Preparation of test locker and general test procedures .10
5.3.4 Temperature test . .21
5.3.5 Water vapour condensation test . 22
5.3.6 Electrical energy consumption test . 23
5.3.7 Heat extraction rate measurement when condensing unit is remote from locker .24
6 Test report .33
6.1 General . 33
6.2 Tests outside test room . 33
6.2.1 Seal test of doors . 33
6.2.2 Linear dimensions, areas and volumes . 34
6.3 Tests inside test room . 34
6.3.1 General test conditions . 34
6.3.2 Cabinet preparation . 34
6.3.3 Temperature test . . 35
6.3.4 Water vapour condensation test . 35
6.3.5 Electrical energy consumption test . 35
6.3.6 Heat extraction rate measurement when the condensing unit is remote from
the cabinet . 35
7 Marking . .36
7.1 Load limit. 36
7.2 Marking plate . 38
7.3 Information to be supplied by the manufacturer . 39
Annex A (normative) Net volume calculation .40
Bibliography . 41

iii
ISO/DIS 19424:2025(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 86 Refrigeration and air-conditioning,
Subcommittee SC 7 Testing and rating of commercial refrigerated display cabinets, in collaboration with
the European Committee for Standardization (CEN) Technical Committee CEN/TC 44, Commercial and
professional refrigerating appliances and systems, performance and energy consumption, in accordance with
the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
DRAFT International Standard ISO/DIS 19424:2025(en)
Refrigerated food lockers — Thermal and energy
performance, ratings, environmental test conditions and
associated testing methods
1 Scope
This standard specifies requirements for the thermal and energy performance of refrigerated food lockers,
in given environmental conditions and intended for the temporary cold storage of chilled or frozen pre-
ordered or pre-selected foodstuff until the final collection by the consumer.
The standard also covers construction characteristics relevant for the thermal and energy performance.
This standard specifies tests conditions and methods for checking the requirements to be satisfied, as well
as classification of refrigerated lockers, their marking and the list of characteristics to be declared by the
manufacturer.
This standard is not applicable to refrigerated vending machines,
It is also not applicable for commercial beverage coolers covered by ISO 22044, ice cream freezers covered
by ISO 22043 and refrigerated display cabinets covered by ISO 23953 as well as to cabinets intended for
storage or cabinets intended for use, for instance, in catering or non-retail refrigerated applications.
This document does not cover health and safety aspects and ergonomic principles.
The standard does not cover safe storage temperatures for any specific perishable foodstuff.
The refrigeration system, providing the cooling function, is either fully or partially integrated or completely
remote from the refrigerated food locker and connected by interconnecting pipe-work.
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.
ISO 23953-1:2023, Refrigerated display cabinets — Part 1: Vocabulary
ISO 23953-2:2023, Refrigerated display cabinets — Part 2: Classification, requirements and test conditions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 23953-1:2023 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/

ISO/DIS 19424:2025(en)
3.1
refrigerated food locker/locker
commercial appliance with chilled, frozen storage temperature zones, intended for the temporary cold
storage of chilled or frozen pre-ordered or pre-selected foodstuff until the final collection by the consumer
Note 1 to entry: Refrigerated food lockers are foreseen for 24/7 h operation and are located inside or outside a building
or under a specific weather protection which is not part of the refrigerated food locker.
Note 2 to entry: The refrigeration system, providing the cooling function, is either fully or partially integrated or
completely remote from the refrigerated food locker and connected by interconnecting pipe-work.
Note 3 to entry: A refrigerated food locker consists of a single or multiple separated cold storage compartments with
chilled, frozen or switchable storage temperature zones.
Note 4 to entry: Compartments are thermally insulated and access to the foodstuff is via a locked door or locked
opening(s).
Note 5 to entry: The loading of the refrigerated food locker with the foodstuff is executed by professional personnel
from the operator either from the front or back and self served by the consumer from the front.
3.2
installation
assembly of compartments, lockers, refrigerating system and all the apparatus necessary for their operation,
which might be connected together on-site to make a complete system
3.3
protected installation
installation specifically designed for outdoor locations and capable of operating under specific range of
outdoor conditions, in accordance with the information provided in the manufacturer’s instructions; it is
sheltered by an incomplete enclosure which includes one or more walls and include a roof, projecting on the
front side of the installation for a length which guarantees protection from dripping water with a maximum
tilt angle of 15°, see Figure 1
Figure 1 — Protected installation
3.4
indoor location
enclosed room or space inside a building, with controlled or uncontrolled environmental conditions
3.5
outdoor location
location outside of any building or structure, exposed to the external atmosphere, with no protection
3.6
harm
injury or damage to the health of people or damage to property of the environment

ISO/DIS 19424:2025(en)
3.7
hazard
potential source of harm
3.8
residual risk
risk remaining after risk reduction measures have been implemented
3.9
risk
combination of the probability of occurrence of harm and severity of that harm
3.10
risk reduction measure
actions or means to eliminate hazards or reduce risks
3.11
net volume
V
N
storage volume inside the appliance which can be used for storage of products
Note 1 to entry: For the calculation method see Annex B .
4 Requirements
4.1 General
Installation environment can be indoor, outdoor and protected characteristics of a protected installation
— avoiding direct sun radiation 1 meter of shadow;
— rain;
— dust;
— wind (probably it exists an ISO standard for wind strength);
— snow loading (for the food locker itself) shall be taken into account 20 kg/sqm for outdoor installation.
4.2 Construction
The cabinet and its parts shall be constructed with adequate strength and rigidity for normal conditions of
handling, transport and use. Attention shall be given to the following:
a) interior fittings, including shelves, baskets, rails, etc. and their supports, shall be sufficiently strong for
the duty required;
b) where sliding shelves, baskets, trays or drawers are fitted they shall retain their shape and ease of
movement when fully loaded;
c) any fitments which are provided with stops to prevent accidental removal shall be self-supporting when
fully loaded and withdrawn to the limit of the stops;
d) stops.
ISO/DIS 19424:2025(en)
4.3 Operating characteristics
4.3.1 Classification according to temperature storage
The performance of cabinets shall comply with one of the classifications defined in Table 1. The performance
shall be verified in accordance with the conditions and test methods specified in Clause 5.
Table 1 — M-package temperature classes
Class Highest temperature, θ , of Lowest temperature, θ , of Lowest temperature, θ ,
ah b al
warmest M-package less than coldest M-package greater of warmest M-package
or equal to than or equal to less than or equal to
(see Figure 9) (see Figure 9) (see Figure 9)
°C
L1 −15 — −18
M1 +5 −1 —
HT +20 +10 —
AF — + 5 —
NOTE 1 HT: High Temperature compartment.
NOTE 2: AF antifreeze.
4.3.2 Classification according to environmental condition
Outdoor installation requires that manufacturer state, additionally to the maximum, also the minimum
environmental classes that the appliance is capable of sustaining with no changes.
Test for a winter condition shall be verified in a cold room, in one of the conditions listed in Table 3 according
to the relevant test of Clause 5.
Classes intended to simulate outdoor winter conditions are specified in Table 3 with a negative value for test
room climate class.
5 Tests
5.1 General
When the characteristics of a locker are to be verified, all the tests shall be applied to one and the same
refrigerated food locker.
All compartments within the locker shall be tested according to the declared temperature classification.
If the locker is capable of operating at different temperature classification., tests shall be carried out at each
classification. Tests shall be carried out for each declared performance within the classes defined in Table 1.
If a locker compartment is specified for multiple product temperature classification, the lowest temperature
is used for testing of temperature performances (5.3.4) and energy consumption (5.3.6).
Lockers shall comply with the requirements specified in clause 4 using the appropriate test method as
described in Table 2.
ISO/DIS 19424:2025(en)
Table 2 — Test summary
Tests Requirement clause Test method Test location
Seal test 4.1 5.2.1 Outside or inside
test
room
Physical dimensions 4.2 5.2.2
(see 5.2)
Temperature 4.3 5.3.4
Inside test
Defrosting 4.3 5.3.4
room
Water vapour condensation 4.3 5.3.5
(see 5.3)
Energy consumption 4.3 5.3.6
heat extraction rate 4.3 5.3.7
5.2 Tests outside or inside test room
The tests that deal with the inspection of construction characteristics, physical dimensions may be carried
out outside the test room.
5.2.1 Seal test for doors
The effectiveness of doors provided to ensure a seal shall be tested as follows (with the locker not running).
Insert a strip of paper 50 mm wide, 0,08 mm thick and of a suitable length at any point of the seal. With the
door closed normally on it the strip of paper shall not slide freely.
NOTE 1 Attention is drawn to the fact that some lockers having doors provided to ensure an air seal are fitted with
decompression valves which allow air to penetrate for a short period of time so that any drop in pressure created
inside the cabinet is compensated. No test is required for such valves.
NOTE 2 The most unfavourable points can be found by inspecting the contact of the seal with the locker closed and
lit from the inside.
5.2.2 Linear dimensions, areas
Measurements shall be made with the locker not in operation but situated in a place where the temperature
is maintained between 16 °C and 30 °C.
For lockers having detachable ends, overall dimensions are given with and without ends. If the locker
includes jacks or other components for adjustment of height, the height defined shall be the minimum height
necessary at installation of the locker.
5.3 Tests inside test room
5.3.1 General
The tests which are carried out inside the test room deal with the assessment of the following characteristics:
— temperature;
— defrosting effect;
— water vapour condensation;
— electrical energy consumption;
— heat extraction rate.
These measurements should be made simultaneously.

ISO/DIS 19424:2025(en)
5.3.2 Test room conditions
In the following, general testing conditions which are common for all tests specified in 5.3.4 to 5.3.7 carried
out inside the test room are defined. These conditions concern the test room, the test and M-packages, and
the measuring instruments.
A test room compliant with the requirements set out in ISO 23953-2:2023, 5.3.2.2 shall be used except when
testing in winter condition as identified in Table 3.
5.3.2.1 Test room — General design, walls, floor and radiant heat
The test room shall be a parallelepiped space in which two of the opposite side walls, referred to as the
discharge technical side wall and the return technical side wall, are designed to create an even, horizontal
air flow within the test room. By convention, the distance separating these two technical side walls is
referred to as the length of the test room.
The minimum useful dimensions (length, width, height) of the test room shall be dependent on the overall
dimensions (length, depth, height) of the refrigerated food locker to be tested and on the location of the
opening of the locker (see 5.3.3.1).
The ceiling and the two non-technical side walls of the room shall be thermally insulated and shall be
equipped with an inner metal skin.
For winter conditions identified in Table 3 the following apply:
— size of the room shall be no less than 20 m and with the appliance placed in the middle with a minimum
of 1 m of free space surrounding the appliance;
— room height shall be at least 1 m higher than the maximum height of the appliance.
A minimum insulation level equivalent to 60 mm of rigid polyurethane foam (λ = 0,03 W/m °C) should be
used for the building of a new test room.
The floor shall be made of concrete or of thermally equivalent material and/or shall be sufficiently insulated
to ensure that external climatic conditions do not affect the floor temperature.
Lighting shall be installed to maintain 600 ± 100 lx measured at a height of 1 m above the floor level and
shall be lit continuously during the test period. The emission spectrum of that lighting device within the
infrared field shall not include peaks of a value of more than 500 W/5 nm/lm.
The walls, ceilings and any partitions of rooms intended for the testing of lockers shall be painted in light
grey (for example, NCS 2706-G90Y or RAL 7032) so that the emissivity is between 0,9 and 1 at 25 °C.
5.3.2.2 Test room (empty) — Thermal and air flow characteristics
An experimental evaluation of the test-room performances shall be carried out minimum once per year
— with test room empty and with lighting switched on,
— in a test-room climate class 3 (see Table 3),
— measuring the velocity, temperature and relative humidity of the air at different points of two vertical
planes parallel to the technical side walls and 600 mm away from the technical side walls, and
— with the climate measuring point located at the geometrical centre of the test room during this evaluation.
These measuring points shall form a two-dimensional grid in which the step is a maximum of 500 mm in the
horizontal and vertical directions. The peripheral line of points shall be located at a maximum of 500 mm
from the other two side walls, floor and ceiling.
A three-dimensional grid inside the test room shall be investigated when obstacles/irregularities projected
into the room of more than 1 m surface area facing the discharge technical side wall exist along the walls.

ISO/DIS 19424:2025(en)
The mean horizontal air velocity measured during 1 min with a maximal interval of 5 s at each of the points
defined above shall lie between 0,1 m/s and 0,2 m/s.
Air temperature measured at each of the points defined above shall not deviate from the rated temperature
of the test-room climate class by more than 2 °C.
The test room shall be capable of maintaining values of humidity within ±3 units of the relative humidity
percentage figures of the rated humidity of the test room temperature class at the specified measuring points.
Surface temperature of walls, ceiling and floor shall be measured in proximity to the points which constitute
the peripheral line of the grid defined above. These surface temperatures shall remain within a tolerance of
±2 °C in relation to the air temperature measured at the nearest point of the grid.
5.3.2.3 Test room climate definition
5.3.2.3.1 Test room climate classes
Tests shall be carried out in at least one of the climate classes defined in Table 3.
During the test, the test room shall be capable of maintaining values of temperature and humidity within
±1 °C of the temperature and ±5 units of the relative humidity percentage figures at the specified climate
measuring point(s) (see 5.3.2.3.2). The exception to this is test-room climate class 3, for which the tolerance
of the relative humidity is instead ±3 units.
Only for test-room climate classes -3; -2 and -1 test room shall be capable of maintaining values of
temperature on climate measuring point(s) within ±2 °C, while the relative humidity is not relevant.
Table 3 — Climate classes
Test room climate Dry bulb tempera- Relative humidity Dew point Water vapour mass
class ture in dry air
°C % °C g/kg
-3 -22 Not relevant Not relevant -
-2 -7 Not relevant Not relevant -
-1 +5 Not relevant Not relevant -
0 20 50 9,3 7,3
1 16 80 12,6 9,1
8 24 55 14,4 10,2
2 22 65 15,2 10,8
3 25 60 16,7 12,0
4 30 55 20,0 14,8
6 27 70 21,1 15,8
5 40 40 23,9 18,8
7 35 75 30,0 27,3
NOTE 1 The water vapour mass in dry air is one of the main points influencing the performance and the energy consumption of
the lockers. Therefore the order of the climate class in the table is based on the water vapour mass column. See also Annex B to
compare lab and store conditions.
NOTE 2 Classes with a negative test room climate class are intended to simulate outdoor winter conditions.
5.3.2.3.2 Climate measuring point
The point for measurement of ambient temperature and relative humidity shall be placed 300 mm upstream
towards the test room air supply wall in accordance with plan view in Figure 2 and section view in Figure 3.
The warm condenser air flow shall be prevented from influencing the temperature at the measuring point
by air deflectors or other suitable means (see 5.3.3.1, Figures 4 and 5).

ISO/DIS 19424:2025(en)
Dimensions in millimetres
Key
1 room air flow
2 locker
3 back
4 front
Figure 2 — Plan of climate measuring point

ISO/DIS 19424:2025(en)
Dimensions in millimetres
Figure 3 — Climate measuring point for one typical example
5.3.2.3.3 Test packages and life-time
Measurement test packages, where foreseen, shall be compliant with specifications of ISO 23953-2:2023,
5.3.2.5, 5.2.3.6 and 5.3.2.7.
5.3.2.3.4 Instruments, measuring equipment and measuring accuracy
All measurements shall be carried out with instruments that have been calibrated.
— Temperature measurements shall be made to an accuracy of ±0,8 °C. Climate temperatures shall be
measured by sensors, inserted in the centre of tinned solid copper or copper-zinc alloy cylinders having
a mass of 25 g and of minimum external area (diameter = height = approximately 12,5 mm).
Specially for the test of a locker intended for connection to an indirect type refrigerating system, secondary
refrigerant temperature difference measurements shall be made to an accuracy of ±0,1 °C (see 5.3.7.2.2).
— Illumination flux per square metre shall be measured to an accuracy of ±10 %.
— Pressures shall be measured to an accuracy of ±1 % during the t period of operation of the locker.
run
— Relative humidity shall be measured to an accuracy of ±3 units of the percentage figure.

ISO/DIS 19424:2025(en)
— Electrical energy consumption shall be measured to an accuracy of ±2 % (see 5.3.6).
— Time interval measurements shall be made to an accuracy of ±1 % or better. All the temperatures are
checked every 60 s.
The time interval for the measurements of refrigerant mass flow rate, inlet/outlet temperature and inlet
and suction pressure shall be less than or equal to 20 s (see 5.3.7.2).
In the case of electronic expansion valves (EEV), measurements shall be sampled at a rate to avoid
undersampling due to the periodic openings of the valve.
NOTE According to the Nyquist - Shannon sampling theorem, undersampling means sampling a periodic signal
with a frequency below 2 times the frequency of the signal itself.
— Air velocity shall be measured using a laboratory-type instrument with an accuracy of 10 % or ±0,03 m/s
whichever is the greater and with a minimum sensitivity of 0,03 m/s in the range of 0 m/s to 1,5 m/s in
horizontal flow at the temperature of the selected ambient class.
— Mass flow rate shall be measured to an accuracy of ±1 % during the t period of operation of the locker
run
(see 5.3.7).
5.3.3 Preparation of test locker and general test procedures
5.3.3.1 Locker selection, installation and positioning within the test room
Each locker intended to be tested, unless a prototype, shall be selected from stock or routine production and
shall be representative as to construction and adjustment.
The locker, including all components required for normal operation, shall be assembled, set up and sited as
it would be installed in service as far as practicable and in accordance with the manufacturer's instructions.
All permanently located accessories required for normal use shall be in their respective places.
The locker shall be located as follows (see Figure 4).
— X = 2 m and B ≥ 1 m for all other lockers;
— Y ≥ 0,8 m for horizontal lockers, vertical lockers;
— A ≥ 0,8 m;
A = Y should be used when A ≥ 1,5 m;
— C ≥ height of locker +0,5 m (for vertical lockers).
The locker shall be located within the test room perpendicularly to the two technical side walls in such a way
that the distances A (and respectively Y) measured at the two ends of the locker is equal with a tolerance of
±4 mm for each meter of length of the locker.
For lockers intended to be placed against a wall, and in order to check the running of lockers with
incorporated condensing unit correctly according to 5.3.2 or the water vapour condensation according to
5.3.4, a vertical partition shall be placed either against the rear of the locker or at a distance d from the rear
p
as specified by the manufacturer (see Figure 4).
The distance, d , between the back of the locker and the vertical panel shall be specified by the manufacturer
p
(see Figure 4). Where this is not specified the locker shall be tested with the partition placed against the
rear of the locker. i.e. distance d = 0.
p
ISO/DIS 19424:2025(en)
Dimensions in millimetres
Key
X distance from the test room air discharge wall
Y distance from the test room front wall
d partition distance specified by the manufacturer
p
1 technical side wall — test room air discharge
2 technical side wall — test room air return
3 vertical partition for wall site locker with same length and height as locker
a Air currents parallel to the plane of the opening (in longitudinal direction).
A distance from the test room back wall
B distance from the test room air return wall
C height of the test room
Figure 4 — Locker location within test room
The air movement of the test room shall be parallel to the longitudinal axis according to 5.3.3.2.

ISO/DIS 19424:2025(en)
The direction of the warm condenser airflow should be the same as the test room air flow direction and not
opposed to it.
a
Air currents parallel to the plane of the opening (in longitudinal direction).
b
Air flow direction of condensing unit.
Figure 5 — Condensing air with test room air flow, or across, but not opposed the test room air flow
5.3.3.2 Air movement
5.3.3.2.1 Climate classes -3; -2; -1
For climate classes -3; -2; -1 (winter conditions) defined in Table 3 the air velocity measured at the internal
environment monitoring point shall be between 1 m/s and 3 m/s in the direction of the length of the locker.
5.3.3.2.2 Climate classes 0 to 8
For climate classes 0 to 8 defined in Table 3 the following applies:
The air movement shall be, as far as practicable, parallel to the plane of the locker opening and to the
longitudinal axis. The length of the locker is defined as the longest horizontal dimension of the opening.

ISO/DIS 19424:2025(en)
With the locker switched off, the mean horizontal air velocity V1, V2 and V3 shall be measured at A1, A2 and
A3 along line A–A in Figure 6 over 1 min with a maximal interval of 5 s. The air velocity of each of the three
points along the line shown shall be 0,15 +0,05/-0,05 m/s.
The average velocity calculated according to Formula (1).
(V 1 + V 2 + V 3) / 3 (1)
shall be 0,15 m/s + 0,03/-0,03.
The verification of the test room air movement shall be carried out under the intended ambient class.
Changes of the test room air velocity after the verification and during the stabilisation and test period are
not allowed.
For lockers with doors hinged in a way that the rotation axis is perpendicular to the longitudinal axis of
the locker the direction of air flow shall be such that the air movement is parallel to the plane of the locker
opening and the air enters the locker when the door(s) is (are) open.
Test room air movement shall be checked during the test in order to be sure that the test room is running
correctly. The method of checking is left to the discretion of testing authority.

ISO/DIS 19424:2025(en)
Dimensions in millimetres
Key
A–A line for the measurement of the air velocity at point A1, A2 and A3
X–X reference line joining the end of the upper part and the end of the lower part of the locker
1 possible location of condensing unit
a
Air currents parallel to the plane of the opening (in longitudinal direction).
Figure 6 — Air movement
5.3.3.3 Loading the locker
5.3.3.3.1 General
Each refrigerated compartment shall be loaded with polystyrene blocks and M-packages.
Three M-packages shall be placed according to 5.3.3.3.2 and 5.3.3.3.3 in the prescribed sensors locations. To
complete the loading, polystyrene blocks shall be arranged in such a way that they form rows with a width
of 200 mm in the direction of the airflow in the compartment for forced-air cooling compartments.
For natural-convection-cooled compartments, or when airflow is coming from the top or the bottom of the
compartment, rows are in the direction of the depth of the compartment.

ISO/DIS 19424:2025(en)
A clearance of 25 mm ± 5 mm shall be left between blocks adjacent to the internal walls of the compartment,
as illustrated in Figure 7.
The locker shall be loaded with test packages and M-packages (see 5.3.2.4 and 5.3.2.5) according to 5.3.3.3.2,
as illustrated in Figure 7. These packages shall be pre-chilled/frozen in order not to overload the thermal
capacity of the locker, to a temperature approximately equal to that expected during the test according to
manufacturer's instructions.
1 000 g packages and 500 g packages should be used.
To complete the loading, use test packages of the following sizes as fillers:
— 25 mm × 100 mm × 200 mm.
The test packages shall be arranged so as to form an even level.
Each refrigerated compartment shall be loaded with test packages arranged in such a way that they form
rows with a width of 200 mm by the depth of the locker in the direction of the airflow in the locker.
A clearance of 25 mm ± 5 mm shall be left between package rows and adjacent to the internal end walls of
the locker.
It is permitted to use partitions with a thickness of approximately 25 mm to position the packages on
condition that they have minimal effect on normal airflow and minimal thermal conduction.
Lengthways, any remaining spaces shall be filled with test packages to obtain one or two adjustment rows
of which the width can measure from 100 mm up to 300 mm.
Depth-wise, any remaining spaces of less than 25 mm wide shall be filled with wooden vertical dividers,
placed approximately midway along the space between two M-packages.
Metallic grids can be used to support the test package loading on M-package rows and the adjacent ones.
5.3.3.3.2 Loading heights
The loading height of each compartment shall be equal to half of the maximum free height, or equal to half of
0mm
the maximum load level if indicated by a load limit line, with a tolerance of .
−25mm
Frontal M-packages shall be located into the upper loading layer; back M-package shall be located into the
lower loading layer, except when the evaporator is on top of the compartment (in this case, it shall be located
into the upper loading layer for each compartment).
5.3.3.3.3 M-package locations
The M-packages shall be placed at the position shown on the locker drawings (see Figure 7).
5.3.3.3.3.1 Longitudinal section
For all compartments with a length less than or equal to 700 mm, frontal M-packages shall be placed into
two transverse sections such that the M-package axis is situated at 50 mm/75 mm from each compartment
end wall. For compartment lengths of more than 700 mm, a third frontal transverse section shall be placed
midway along
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