SIST EN 16798-3:2025

SLOVENSKI STANDARD
01-julij-2025
Nadomešča:
SIST EN 16798-3:2018
Energijske lastnosti stavb - Prezračevanje stavb - 3. del: Prezračevanje
nestanovanjskih stavb - Zahtevane lastnosti za sisteme prezračevanja in
klimatizacije prostorov (modula M5-1, M5-4)
Energy performance of buildings - Ventilation for buildings - Part 3: For non-residential
buildings - Performance requirements for ventilation and room-conditioning systems
(Modules M5-1, M5-4)
Energetische Bewertung von Gebäuden - Lüftung von Gebäuden - Teil 3: Lüftung von
Nichtwohngebäuden -Leistungsanforderungen an Lüftungs- und Klimaanlagen und
Raumkühlsysteme (Module M5-1, M5-4)
Performance énergétique des bâtiments - Ventilation des bâtiments - Partie 3: Pour
bâtiments non résidentiels - Exigences de performances pour les systèmes de
ventilation et de climatisation (Modules M5-1, M5-4)
Ta slovenski standard je istoveten z: EN 16798-3:2025
ICS:
91.140.30 Prezračevalni in klimatski Ventilation and air-
sistemi conditioning systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 16798-3
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2025
EUROPÄISCHE NORM
ICS 91.120.10; 91.140.30 Supersedes EN 16798-3:2017
English Version
Energy performance of buildings - Ventilation for buildings
- Part 3: For non-residential buildings - Performance
requirements for ventilation and room-conditioning
systems (Modules M5-1, M5-4)
Performance énergétique des bâtiments - Ventilation Energetische Bewertung von Gebäuden - Lüftung von
des bâtiments - Partie 3 : Pour bâtiments non Gebäuden - Teil 3: Lüftung von Nichtwohngebäuden -
résidentiels - Exigences de performances pour les Leistungsanforderungen an Lüftungs- und
systèmes de ventilation et de climatisation (Modules Klimaanlagen und Raumkühlsysteme (Module M5-1,
M5-1, M5-4) M5-4)
This European Standard was approved by CEN on 3 February 2025.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 16798-3:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 5
Introduction . 8
1 Scope . 10
2 Normative references . 13
3 Terms and definitions . 14
4 Symbols and subscripts . 16
5 Description of the method and routing . 17
5.1 Output of the method. 17
5.2 General description of the method . 17
5.2.1 Input data for energy calculation . 17
5.2.2 Source of data for energy calculation . 18
6 Output data for energy calculation . 19
7 Indoor environment . 19
7.1 General . 19
7.2 Occupied zone . 20
8 Agreement of design criteria . 22
8.1 General . 22
8.2 Principles . 22
8.3 General building characteristics . 22
8.3.1 Location, outdoor conditions, neighbourhood. 22
8.3.2 Design weather data . 22
8.3.3 Information on the operation of the building. 23
8.4 Construction data . 23
8.5 Geometrical description . 23
8.6 Use of the rooms . 23
8.6.1 General . 23
8.6.2 Human occupancy . 23
8.6.3 Internal heat gains . 23
8.6.4 Internal pollution and moisture sources . 23
8.6.5 Given extract airflow . 23
8.7 Requirements in the rooms . 24
8.7.1 General . 24
8.7.2 Type of control . 24
8.7.3 Thermal comfort . 24
8.7.4 Air quality for people. 24
8.7.5 Noise level . 24
8.7.6 Lighting . 24
8.8 System requirements . 24
8.9 Heat transmission of surfaces of ventilation systems . 25
8.10 General requirements for control, adjustment and monitoring . 25
8.11 General requirements for maintenance and safety of operation . 25
8.12 Process from project initiation to operation . 26
8.13 Supply air humidity . 26
9 Classification . 27
9.1 Specification of types of air . 27
9.2 Classification of air . 29
9.2.1 Extract air and exhaust air . 29
9.2.2 Outdoor air . 30
9.2.3 Supply air . 31
9.2.4 Indoor air . 33
9.2.5 Exhaust air . 33
9.2.6 Recirculation and secondary air . 33
9.3 System functions and basic system types . 33
9.3.1 General . 33
9.3.2 Types and configurations . 34
9.3.3 Controls and operation . 35
9.4 Design air flow balance. 36
9.5 Specific fan power . 37
9.5.1 General . 37
9.5.2 Classification of specific fan power . 38
9.5.3 Calculating the power demand of the fan . 39
9.5.4 Specific Fan Power of an entire building . 39
9.5.5 Specific Fan Power of Individual Air Handling Units . 39
9.5.6 AHU related P values . 40
SFP
9.6 Heat recovery section. 41
9.6.1 General . 41
9.6.2 Requirements for heat recovery . 42
9.6.3 Transfer of humidity . 42
9.6.4 Icing and defrosting . 43
9.6.5 Transfer of pollutants . 43
9.7 Filtration . 43
9.7.1 General aspects . 43
9.7.2 Filter maintenance . 44
9.8 Leakages in ventilation systems. 45
9.8.1 General . 45
9.8.2 Leakages in heat recovery section . 45
9.8.3 Classification of outdoor air correction factor at heat recovery systems . 46
9.8.4 Leakages at Air Handling unit (AHU) casing . 46
9.8.5 Filter bypass leakages . 46
9.8.6 Leakages of air distribution systems . 47
10 Calculation and energy rating . 48
10.1 Ventilation effectiveness, contamination removal effectiveness and air diffusion . 48
10.1.1 General . 48
10.1.2 Calculation of ventilation air volume flow . 48
10.2 Calculation of air volume flow rates . 49
10.2.1 Design air volume flow design based on heating, cooling loads and dehumidification . 49
10.2.2 Extract air flow rates . 50
10.3 Energy rating of ventilation systems . 50
10.3.1 General . 50
10.3.2 Specific Fan Power of an entire building . 50
10.3.3 Heat recovery efficiency . 50
10.3.4 Primary energy use of ventilation . 51
Annex A (normative) Input and method selection data sheet — Template . 52
A.1 General . 52
A.2 References . 53
A.3 Design data for energy calculation — Typical range for SFP categories. 53
A.4 Design data . 54
Annex B (informative) Input and method selection data sheet — Default choices . 55
B.1 General . 55
B.2 References . 55
B.3 Default design data for energy calculation . 57
B.4 Default design data . 58
Annex C (normative) Requirements for intake and exhaust openings . 59
C.1 Intake and exhaust openings . 59
Annex D (informative) Recirculation and secondary air filtration quality to reduce airborne
pathogens. 66
D.1 General . 66
D.2 Recirculation and secondary air quality classes . 67
D.3 Recommended air filter classes . 68
D.4 Recommendations for system design . 69
Annex E (informative) National Data for Design Criteria — Default choices . 70
E.1 General . 70
E.2 Design weather data . 70
E.3 Air classification . 71
E.4 Distance between intake and exhaust for roof mounted air handling units . 71
E.5 Space recommendations for components and systems . 73
E.6 Example for classification of outdoor air . 77
Bibliography. 81
European foreword
This document (EN 16798-3:2025) has been prepared by Technical Committee CEN/TC 156 “Ventilation
for buildings” the secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by October 2025, and conflicting national standards shall
be withdrawn at the latest by October 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 16798-3:2017.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
This document includes the following significant technical changes with respect to EN 16798-3:2017:
— new structure to clarify designing and calculation aspects;
— update of filtration aspects;
— update of heat recovery aspects and leakages in these systems;
— update of aspects of energy performance;
— update of definitions of systems;
— update of SFP definitions and links to Regulation (EU) No 327/2011;
— addition of an informative Annex C for additional design aspects, which has been shifted from
CEN/TR 16798-4;
— the document allows a normative national annex.
EN 16798-3:2017 was produced to meet the requirements of Directive 2002/91/EC 16 December 2002
on energy performance of buildings referred to as “EPBD”.
This document has been produced to meet the requirements of Directive 2010/31/EU 19 May 2010 on
the energy performance of buildings (recast), referred to as “recast EPDB”.
For the convenience of Standards users CEN/TC 156, together with responsible Working Group
Conveners, have prepared a simple Table below relating, where appropriate, the ‘EPBD’ standard
numbers prepared by Technical Committee CEN/TC 156 “Ventilation for buildings”.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North
Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the United
Kingdom.
Recast EPBD
Title
EN Number
Energy performance of buildings — Ventilation for buildings — Part 1: Indoor
environmental input parameters for design and assessment of energy
EN 16798-1
performance of buildings addressing indoor air quality, thermal environment,
lighting and acoustics (Module M1-6)
Energy performance of buildings — Ventilation for buildings — Part 2:
Interpretation of the requirements in EN 16798-1 — Indoor environmental input
CEN/TR 16798-2 parameters for design and assessment of energy performance of buildings
addressing indoor air quality, thermal environment, lighting and acoustics
(Module M1-6)
Energy performance of buildings — Ventilation for buildings — Part 3: For non-
EN 16798-3 residential buildings — Performance requirements for ventilation and room-
conditioning systems (Modules M5-1, M5-4)
Energy performance of buildings — Ventilation for buildings — Part 4:
Interpretation of the requirements in EN 16798-3 — For non-residential
CEN/TR 16798-4
buildings — Performance requirements for ventilation and room-conditioning
systems (Modules M5-1, M5-4)
Energy performance of buildings — Ventilation for buildings — Part 5-1:
Calculation methods for energy requirements of ventilation and air conditioning
EN 16798-5-1
systems (Modules M5-6, M5-8, M6-5, M6-8, M7-5, M7-8) — Method 1:
Distribution and generation
Energy performance of buildings — Ventilation for buildings — Part 5-2:
EN 16798-5-2 Calculation methods for energy requirements of ventilation systems
(Modules M5-6.2, M5-8.2) — Method 2: Distribution and generation
Energy performance of buildings — Ventilation for buildings — Part 6:
Interpretation of the requirements in EN 16798-5-1 and EN 16798-5-2 —
CEN/TR 16798-6
Calculation methods for energy requirements of ventilation and air conditioning
systems (Modules M5-6, M5-8, M6-5, M6-8, M7-5, M7-8)
Energy performance of buildings — Ventilation for buildings — Part 7:
EN 16798-7 Calculation methods for the determination of air flow rates in buildings
including infiltration (Module M5-5)
Energy performance of buildings — Ventilation for buildings — Part 8:
Interpretation of the requirements in EN 16798-7 — Calculation methods for the
CEN/TR 16798-8
determination of air flow rates in buildings including infiltration — (Module M5-
5)
Energy performance of buildings — Ventilation for buildings — Part 9:
EN 16798-9 Calculation methods for energy requirements of cooling systems (Modules M4-1,
M4-4, M4-9) — General
Energy performance of buildings — Ventilation for buildings — Part 10:
CEN/TR 16798-10 Interpretation of the requirements in EN 16798-9 — Calculation methods for
energy requirements of cooling systems (Module M4-1,M4-4, M4-9) — General
Recast EPBD
Title
EN Number
Energy performance of buildings — Ventilation for buildings — Part 13:
EN 16798-13
Calculation of cooling systems (Module M4-8) — Generation
Energy performance of buildings — Ventilation for buildings — Part 14:
CEN/TR 16798-14 Interpretation of the requirements in EN 16798-13 — Calculation of cooling
systems (Module M4-8) — Generation
Energy performance of buildings — Ventilation for buildings — Part 15:
EN 16798-15
Calculation of cooling systems (Module M4-7) — Storage
Energy performance of buildings — Ventilation for buildings — Part 16:
CEN/TR 16798-16 Interpretation of the requirements in EN 16798-15 — Calculation of cooling
systems (Module M4-7) — Storage
Energy performance of buildings — Ventilation for buildings — Part 17:
EN 16798-17 Guidelines for inspection of ventilation and air-conditioning systems (Module
M4-11, M5-11, M6-11, M7-11)
Energy performance of buildings — Ventilation for buildings — Part 18:
Interpretation of the requirements in EN 16798-17 — Guidelines for inspection
CEN/TR 16798-18
of ventilation and air-conditioning systems (Module M4-11, M5-11, M6-11, M7-
11)
Introduction
This document is part of a series of standards aiming at European harmonization of the methodology for
the assessment of the energy performance of buildings, called “set of EPB standards”.
The set of EPB standards follow specific rules to ensure overall consistency, unambiguity and
transparency.
The set of EPB standards provide a certain flexibility with regard to the methods, the required input data
and references to other EPB standards, by the introduction of a template for national default choices in
Annex A and with informative default choices in Annex B.
For the correct use of this document, a normative template is given in Annex A to specify these choices.
Informative default choices are provided in Annex B.
The main target groups of this document are all the users of the set of EPB standards (e.g. architects,
engineers, regulators).
Use by or for regulators: In case the standard is used in the context of national or regional legal
requirements, mandatory choices may be given at national or regional level for such specific applications.
These choices (either the informative default choices from Annex B or choices adapted to national or
regional needs, but in any case, following the template of this Annex A) can be made available as national
Annex or as separate (e.g. legal) document (national data sheet).
NOTE So in this case:
• the regulators specify the choices;
• the individual user applies the document to assess the energy performance of a building, and thereby use the
choices made by the regulators.
Topics addressed in this document can be subject to public regulation. Public regulation on the same
topics can override the default values in Annex B of this document. Public regulation on the same topics
can even, for certain applications, override the use of this document. Legal requirements and choices are
in general not published in standards but in legal documents. In order to avoid double publications and
difficult updating of double documents, a national Annex may refer to the legal texts where national
choices have been made by public authorities. Different national annexes or national data sheets are
possible, for different applications.
It is expected, if the default values, choices and references to other EPB standards in Annex B are not
followed due to national regulations, policy or traditions, that:
— national or regional authorities prepare data sheets containing the choices and national or regional
values, according to the model in Annex A. In this case the national Annex (e.g. NA) refers to this text;
— or, by default, the national standards body will consider the possibility to add or include a national
Annex in agreement with the template of Annex A, in accordance with the legal documents that give
national or regional values and choices.
Further target groups are parties wanting to motivate their assumptions by classifying the building
energy performance for a dedicated building stock.
This document also provides specifications especially for designers, installers, manufacturers, building
owners and users, on fan assisted ventilation (see Figure 1), air-conditioning and room-conditioning
systems in order to achieve a comfortable and healthy indoor environment in all seasons with
acceptable installation and running costs. This document focuses on the system-aspects for typical
applications and covers the following:
— aspects important to achieve and maintain a good energy performance in the systems without any
negative impact on the quality of the indoor environment;
— definitions of design and performances data.
More information is provided in the Technical Report accompanying this document (CEN/TR 16798-4).
For the designing use of this document, an informative default Annex providing additional design
parameters is given with Annex C. CEN Members are free to use Annex C or supplement this document
with their national design parameters in a national foreword.

Figure 1 — Generic concept relation of air replacement
1 Scope
This document applies to the design, energy performance of buildings and implementation of ventilation,
air conditioning and room conditioning systems for non-residential buildings subject to human
occupancy, excluding applications like industrial processes. It focuses on the definitions of the various
parameters that are relevant for such systems.
The guidance for design given in this document and accompanying CEN/TR 16798-4 are mainly
applicable to mechanical supply and/or exhaust ventilation systems. Natural ventilation systems or
natural parts of hybrid ventilation systems are not covered by this document.
Applications for residential ventilation are not covered in this document. Performance of ventilation
systems in residential buildings is covered in EN 15665 and CEN/TR 14788.
The classification uses different categories. For some values, examples are given and, for requirements,
typical ranges with default values are presented. The default values are given in Annex B and a template
for national specification is given in Annex A. It is important that the classification is always appropriate
to the type of building and its intended use, and that the basis of the classification is explained if the
examples given in this document are not used.
NOTE 1 Different standards can express the categories for the same parameters in a different way, and also the
category symbols can be different.
Table 1 shows the relative position of this document within the set of EPB standards in the context of the
modular structure as set out in EN ISO 52000-1.
NOTE 2 In CEN ISO/TR 52000-2 the same Table can be found, with, for each module, the numbers of the relevant
EPB standards and accompanying technical reports that are published or in preparation.
NOTE 3 The modules represent EPB standards, although one EPB standard might cover more than one module
and one module might be covered by more than one EPB standard, for instance a simplified and a detailed method
respectively. See also Clause 2 and Table A.1 and Table B.1.
Table 1 — Position of this standard (in case M5-1, M5-4), within the modular structure of the set of EPB standards
Building
Overarching   Technical Building Systems
(as such)
sub1 M1  sub1 M2  sub1  M3 M4 M5 M6 M7 M8 M9 M10 M11
1 General  1 General  1 General   EN 16798-3
Common terms
and definitions; Building Energy
2  2  2 Needs
symbols, units Needs
and subscripts
(Free) Indoor
Maximum
Conditions
3 Applications  3  3 Load and
without
Power
Systems
Ways to
Ways to Ways to
Express
4 Express Energy  4 Express Energy  4   EN 16798-3
Energy
Performance Performance
Performance
Building
Heat Transfer
Functions and Emission and
5  5 by  5
Building control
Transmission
Boundaries
Building
Heat Transfer
Occupancy and Distribution
6  6 by Infiltration  6
Operating and control
and Ventilation
Conditions
Descriptions
Descriptions
Descriptions
Heating
Cooling
Ventilation
Humidification
Dehumidification
Domestic hot
water
Lighting
Building
automation and
control
PV, wind, .
Aggregation of
Energy
Internal Heat Storage and
7 Services and  7  7
Gains control
Energy
Carriers
Building Solar Heat Generation
8  8  8
Partitioning Gains and control
Load
Calculated Building dispatching
9 Energy  9 Dynamics  9 and
Performance (thermal mass) operating
conditions
Measured Measured Measured
10 Energy  10 Energy  10 Energy
Performance Performance Performance
11 Inspection  11 Inspection  11 Inspection
Ways to
12 Express Indoor     12 BMS
Comfort
External
13 Environment
Conditions
Economic
Calculation
NOTE The shaded modules are not applicable.
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.
NOTE 1 Default references to EPB standards other than EN ISO 52000-1 are identified by the EPB module code
number and given in Annex A (normative template) and Annex B (informative default choice).
NOTE 2 Example of EPB module code number: M5-5, or M5-5.1 (if module M5-5 is subdivided), or M5-5/1 (if
reference to a specific clause of the standard covering M5-5).
EN 308, Heat exchangers — Test procedures for establishing performance of air to air heat recovery
components
CEN/TS 16628, Energy Performance of Buildings — Basic Principles for the set of EPB standards
CEN/TS 16629, Energy Performance of Buildings — Detailed Technical Rules for the set of EPB-standards
EN 1822-1, High efficiency air filters (EPA, HEPA and ULPA) — Part 1: Classification, performance testing,
marking
EN 1886, Ventilation for buildings — Air handling units — Mechanical performance
EN 12599:2012, Ventilation for buildings — Test procedures and measurement methods to hand over air
conditioning and ventilation systems
EN 12792:2003, Ventilation for buildings — Symbols, terminology and graphical symbols
EN 13053, Ventilation for buildings — Air handling units — Rating and performance for units, components
and sections
EN ISO 7345:2018, Thermal performance of buildings and building components — Physical quantities and
definitions (ISO 7345:2018)
EN ISO 16890 (all parts), Air filters for general ventilation (ISO 16890 (all parts))
EN ISO 52000-1:2017, Energy performance of buildings — Overarching EPB assessment — Part 1: General
framework and procedures (ISO 52000-1:2017)
EN ISO 10121-3, Test methods for assessing the performance of gas-phase air cleaning media and devices
for general ventilation — Part 3: Classification system for GPACDs applied to treatment of outdoor air
(ISO 10121-3)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 12792:2003, M1-6 and M1-9,
EN ISO 7345:2018, EN ISO 52000-1 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/
The terms of EN ISO 52000-1 that are indispensable for the understanding of the underlying standard
are repeated here.
3.1
EPB standard
standard that complies with the requirements given in EN ISO 52000-1, CEN/TS 16628 and
CEN/TS 16629
Note 1 to entry: CEN/TS 16628 and CEN/TS 16629 contain specific rules to ensure overall consistency,
unambiguity, transparency and flexibility, supported by common templates. EN ISO 52000-1, the overarching EPB
standard, is indispensable for each EPB standard, because of the modular structure, common terms and definitions,
symbols and subscripts and because it provides the general framework for the EPB assessment.
[SOURCE: EN ISO 52000-1:2017, 3.5.14, modified – deleted original Note to entry and added new Note to
entry ]
3.2
room conditioning system
combination of appliances designed to keep comfort conditions in a room within a defined range
Note 1 to entry: Air conditioning systems as well as surface based systems, such as embedded systems, chilled
ceilings and chilled beams, are included, see Table 13.
3.3
occupied zone
volume designed for human occupancy specified by horizontal and vertical planes
Note 1 to entry: For a description of an occupied zone see also Figure 2.
3.4
ventilation effectiveness
contamination removal effectiveness
CRE
performance of a room air distribution system and diffusion system in removing the pollutants from the
occupied zone of a room given by relation between the pollution concentrations in the supply air, the
extract air and the indoor air in the breathing zone (within the occupied zone)
3.5
specific fan power
amount of electric fan power divided by the air volume flow
3.6
demand controlled ventilation system
ventilation system where the ventilation rate is controlled by air quality, moisture, occupancy or some
other indicator for the need of ventilation
3.7
ventilation system
combination of appliances designed to supply interior spaces with outdoor air and to extract polluted
indoor air
Note 1 to entry: The system can consist of mechanical components (e.g. combination of air handling unit, ducts and
terminal units). Ventilation system can also refer to natural ventilation systems making use of temperature
differences and wind with facade grills in combination with mechanical exhaust (e.g. in corridors, toilets; etc.). Both
mechanical and natural ventilation can be combined with operable windows. A combination of mechanical and non-
mechanical components is possible (hybrid systems).
3.8
Exhaust Air Transfer Ratio
EATR
transfer of exhaust air into the supply air side which provides information on the ratio of exhaust air in
the supply air
3.9
Outdoor Air Correction Factor
OACF
S
ratio of the entering supply mass air flow rate and the leaving supply mass air flow rate, which provides
information about the leakages between the air flows
3.10
design nominal air flow
−3
declared nominal air volume flow at a density of 1,2 kg∙m
3.11
air conditioning system
combination of appliances designed to supply conditioned air to a space
Note 1 to entry: For types of ventilation-, air-conditioning-, and room conditioning-systems based on functions, see
Table 13.
3.12
reference conditions
P
SFP
clean filters and dry conditions for other components (e.g. heat exchanger, cooling
coil and humidifier)
3.13
design load conditions
P
SFPd
average of clean filters and recommended maximum pressure drop and, for other
components (heat exchanger, cooling coil, humidifier, etc.), the average of dry and wet values
4 Symbols and subscripts
For the purposes of this document, the symbols given in Clause 4 and in EN ISO 52000-1:2017,
Annex C, EN 12792 and the specific symbols listed in Table 2 apply.
For the purposes of this document, the subscripts given in Clause 4 and in of EN ISO 52000-1:2017,
Annex C apply.
Table 2 — Symbols and units
Quantity Symbol Unit
Pressure difference Δp Pa
Area A m
b
Costs C €
−3
Concentration c mg∙m
−1 −1
Specific heat capacity at constant pressure c J∙kg ∙K
p
Diameter d m
Energy consumption (measured) E J
Energy demand (calculated) E J
Exhaust Air Transfer R
...