prEN 16282-1

Equipment for commercial kitchens - Components for ventilation of commercial kitchens - Part 1: General requirements including calculation method

This standard applies to kitchen ventilation systems in kitchens and other companies processing foodstuffs intended for commercial use from their nature and finish. It does not apply to household kitchens. This standard stipulates the general requirements, such as ergonomic aspects of the Kitchen room (temperature, wind aspects, moisture, noise, etc.), including the method for calculation for the airflows and their testing.

Großküchengeräte - Einrichtungen zur Be- und Entlüftung von gewerblichen Küchen - Teil 1: Allgemeine Anforderungen einschließlich Berechnungsmethoden

Diese Norm gilt für Verteilerküchen, Lüftungsanlagen in gewerblichen Küchen und die damit verbundenen Bereiche und anderen Anlagen und anderen lebensmittelverarbeitenden Betrieben in gewerblichen Küchen. Küchen und zugehörige Bereiche sind Sonderräume, in denen Speisen zubereitet, ausgegeben und verteilt werden, Geschirr und Geräte gespült und Nahrungsmittel gelagert werden. Diese Norm gilt nicht für Küchen im Haushaltsbereich.
Diese Norm legt die allgemeinen Anforderungen wie ergonomische Aspekte in Bezug auf die Belüftung der Küche (Temperatur, Luftaspekte, Feuchtigkeit, Lärm usw.) inklusive der Berechnung des Luftstroms und des Prüfung fest

Équipement pour grande cuisine - Installation pour la ventilation de cuisines professionnelles - Partie 1: Exigences générales et méthode de calcul

La présente norme concerne les systèmes de ventilation répartis dans les cuisines professionnelles, les surfaces associées et les autres installations de transformation des produits alimentaires destinées à un usage professionnel. Les cuisines et les zones associées sont des salles spéciales dans lesquelles les repas sont préparés et divisés, la vaisselle et les ustensiles sont lavés et nettoyés et les denrées alimentaires sont stockées.
La présente norme ne s'applique pas aux cuisines domestiques.
La présente norme spécifie les exigences générales, telles que les aspects ergonomiques en rapport avec la ventilation de la cuisine (température, aspects liés à l'air, humidité, bruit, etc.), ainsi que la méthode de calcul des débits d'air et les essais.

Oprema za komercialne kuhinje - Sestavni deli za prezračevanje v komercialnih kuhinjah - 1. del: Splošne zahteve, vključno z računskimi metodami

General Information

• Status: Not Published
• Publication Date: 18-Nov-2013
• Withdrawal Date: 18-May-2014
• ICS: 97.040.99 - Other kitchen equipment
• Technical Committee: CEN/TC 156 - Ventilation for buildings
• Drafting Committee: CEN/TC 156/WG 14 - Ventilation of commercial kitchens
• Current Stage: 4098 - Decision to abandon - Enquiry
• Start Date: 08-Apr-2013
• Completion Date: 08-Apr-2013
• Ref Project: oSIST prEN 16282-1:2011 - Equipment for commercial kitchens - Components for ventilation of commercial kitchens - Part 1: General requirements including calculation method

Overview

prEN 16282-1 (Equipment for commercial kitchens - Components for ventilation of commercial kitchens - Part 1) is a CEN draft standard that sets general requirements and a calculation method for ventilation systems in commercial and other non‑household kitchens that process food for commercial use. It addresses ergonomic and hygiene aspects (temperature, humidity, air velocity, noise), pollutant and heat loads, classification of kitchen types, and methods to calculate supply and exhaust airflows including capture and containment principles. Note: the document provided is the draft (prEN) submitted for enquiry.

Key topics and technical requirements

• Scope and applicability: Applies to commercial kitchens and associated rooms; excludes household kitchens. Covers design, testing and airflow calculation methods.
• Ergonomics & indoor environment: Thermal comfort, PMV/PPD references (EN ISO 7730), room air temperature, humidity, air velocity and acoustic requirements.
• Contaminant control: Removal of odours, grease particles and combustion gases; hygiene zones (cold, hot, meat/fish prep, dishwashing).
• Airflow calculation methods:
  • Pre‑dimensioning approaches (hourly air changes, capture velocity methods).
  • Detailed thermally induced airflow and hood extraction calculations.
  • Use of symbols/metrics like ACH (air changes per hour), capture velocity, volumetric airflow (m3/h).
• System design principles: Supply/exhaust balance, avoidance of pollutant backflow, placement of heat‑emitting appliances to optimise ventilation needs.
• Equipment & components: Requirements for hoods, ceilings, ducts, AHUs, filters and cleaning access; references to cleaning and maintenance.
• Testing and verification: Annexes include tables for dimensioning and worked calculation examples to support design checks.

Practical applications

• Design and specification of ventilation systems for restaurants, institutional kitchens, catering facilities, hotels, hospitals and large food‑service operations.
• Sizing kitchen hoods, exhaust and supply air systems, air handling units (AHUs), and ductwork to meet hygiene, comfort and safety objectives.
• Preparing performance specifications, tender documents and compliance checks for building projects and retrofits.
• Informing maintenance requirements and cleaning schedules to preserve capture efficiency and indoor air quality.

Who should use this standard

• HVAC engineers and ventilation designers
• Kitchen and catering equipment manufacturers
• Architects and building services consultants
• Facility managers, health & safety officers and building owners
• Regulatory bodies and testing laboratories

Related standards

• prEN 16282 series (Parts 2–9 cover hoods, ceilings, inlets/outlets, ducts, aerosol separators, fire suppression, treatment and test methods)
• EN ISO 7730, EN 12792, EN 13779, EN 15251 (referenced normative standards)

Keywords: prEN 16282-1, commercial kitchen ventilation, kitchen hood design, capture velocity, airflow calculation, kitchen ventilation standard, AHU, air changes per hour.

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2011
2SUHPD]DNRPHUFLDOQHNXKLQMH6HVWDYQLGHOL]DSUH]UDþHYDQMHYNRPHUFLDOQLK
NXKLQMDKGHO6SORãQH]DKWHYHYNOMXþQR]UDþXQVNLPLPHWRGDPL
Equipment for commercial kitchens - Components for ventilation of commercial kitchens -
Part 1: General requirements including calculation method
Großküchengeräte - Einrichtungen zur Be- und Entlüftung von gewerblichen Küchen -
Teil 1: Allgemeine Anforderungen einschließlich Berechnungsmethoden
Équipement pour grande cuisine - Installation pour la ventilation de cuisines
professionnelles - Partie 1: Exigences générales et méthode de calcul
Ta slovenski standard je istoveten z: prEN 16282-1
ICS:
91.140.30 3UH]UDþHYDOQLLQNOLPDWVNL Ventilation and air-
VLVWHPL conditioning
97.040.99 Druga kuhinjska oprema Other kitchen equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
DRAFT
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2011
ICS 97.040.99
English Version
Equipment for commercial kitchens - Components for ventilation
of commercial kitchens - Part 1: General requirements including
calculation method
Équipement pour grande cuisine - Installation pour la Großküchengeräte - Einrichtungen zur Be- und Entlüftung
ventilation de cuisines professionnelles - Partie 1: von gewerblichen Küchen - Teil 1: Allgemeine
Exigences générales et méthode de calcul Anforderungen einschließlich Berechnungsmethoden
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 156.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

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.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 16282-1:2011: E
worldwide for CEN national Members.

Contents Page
Foreword .4
1 Scope .5
2 Normative references .5
3 Terms, definitions and classification .5
3.1 capture velocity.5
4 Symbols and abbreviations .5
5 Objectives of kitchen ventilation .6
6 Classification of kitchens .7
7 Basic design principles .7
7.1 General .7
7.2 Heat and substance loads .9
7.3 Further notes .9
8 Ergonomic and hygiene requirements .9
8.1 Thermal comfort, tolerance .9
8.2 Temperature of room air . 10
8.3 Humidity of room air . 11
8.4 Air velocity in the room . 11
8.5 Noise control . 12
8.6 Hygiene requirements . 12
9 Air circulation within the room . 13
9.1 Basic types of airflow . 13
9.2 Mixed flow . 13
9.3 Laminar flow (displacement) . 13
10 Design principles . 14
10.1 General . 14
10.2 Pre-dimensioning. 15
10.2.1 General . 15
10.2.2 Hourly air replacement method based on the kitchen size . 15
10.2.3 Method based on the capture velocity . 15
10.2.4 Guide values for ancillary rooms . 16
10.3 Dimensioning - detailed method . 16
10.3.1 Thermally induced airflow . 16
10.3.2 Extraction airflows for kitchen extraction hoods . 17
10.3.3 Exhaust airflows in connection with kitchen extraction hoods . 19
10.3.4 Exhaust airflows in connection with kitchen air extraction ceilings . 19
10.3.5 Check calculation . 20
10.3.6 Supply airflows . 20
11 Ventilation and air conditioning systems . 20
11.1 Exhaust air systems . 20
11.2 Supply air systems . 21
11.3 Air handling units . 21
11.4 System components . 21
11.4.1 System cleaning. 21
11.4.2 Supply and exhaust air component . 21
11.4.3 Filters . 22
11.4.4 Air openings for outside and outgoing air . 22
12 Gas-heated catering kitchen appliances . 22
Annex A (normative) Tables for dimensioning . 23
Annex B (normative) Calculation examples . 29
Bibliography . 37

Foreword
This document (prEN 16282-1:2011) has been prepared by Technical Committee CEN/TC 156 “Ventilation for
buildings”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
The structure of the standard series is as follows:
prEN 16282 Equipment for commercial kitchens – Components for ventilation in commercial kitchens
 Part 1: General requirements including calculation method
 Part 2: Kitchen ventilation hoods – Design and safety requirements
 Part 3: Kitchen ventilation ceilings – Design and safety requirements
 Part 4: Air inlets and outlets – Design and safety requirements
 Part 5: Air duct – Design and dimensioning
 Part 6: Aerosol separators – Design and safety requirements
 Part 7: Installation and use of fixed fire suppression systems
 Part 8: Installation for treatment of cooking fumes – Requirements and tests
 Part 9: Capture and containment performance of extraction systems for commercial kitchen – test
methods
1 Scope
This standard is intended for dispatched kitchen ventilation systems in commercial kitchens, associated areas
and other installations processing foodstuffs intended for commercial use. Kitchens and associated areas are
special rooms in which meals are prepared and detached, and where tableware and equipment is washed and
cleaned and food is stored.
This standard does not apply to household kitchens.
This standard stipulates the general requirements, such as ergonomic aspects in relation to ventilation of the
kitchen (temperature, air aspects, moisture, noise, etc.), including the method for calculating the airflows and
testing.
2 Normative references
The following referenced documents are indispensable for the application 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.
prEN 16282-5, Equipment for commercial kitchens – Components for ventilation in commercial kitchens –
Part 5: Air duct – Design and dimensioning
EN ISO 7730, Ergonomics of the thermal environment - Analytical determination and interpretation of thermal
comfort using calculation of the PMV and PPD indices and local thermal comfort criteria (ISO 7730:2005)
EN 12792, Ventilation for buildings – Symbols, terminology and graphical symbols
EN 13779, Ventilation for non-residential buildings – Performance requirements for ventilation and room-
conditioning systems
EN 15251, Indoor environmental input parameters for design and assessment of energy performance of
buildings addressing indoor air quality, thermal environment, lighting and acoustics
3 Terms, definitions and classification
For the purposes of this European Standard, the terms and definitions given in EN 12792 together with the
following apply.
3.1 capture velocity
Airflow velocity in the free space between the lower part of the hood and the cooking appliance
4 Symbols and abbreviations
For the purposes of this European Standard, the symbols and abbreviations given in EN 12792, together with
the following, apply:
ACH air changes per hour
q airflow in the extraction hood in m /h
v-ext
v capture air velocity in m/s
P perimeter of the hoods in m
z height above the heat source in m
h appliance height in m
&
V volumetric airflow in m /h
&
Q convectively-transmitted proportion of the direct heat load in W
S,K
&
Q sensitive thermal output in W
S
convective
k
b degree of pollution -
&
thermic flow in m /h
V
th
4/3 -1/3 -1
k empirically-determined coefficient in m W h
ϕ simultaneity factor -
r reduction factor for thermal flow -
d hydraulic diameter in m
hydr
L Length in m
B Width in m
&
V Extraction airflows for extraction hoods in m /h
Erf
a allowance factor -
e capture and containment efficiency in %
eff
&
V total airflow in m /h
th,ne
&
V exhaust airflows in m /h
ABL
&
V compensation airflow in m /h
Ausgl
m& mess flow In kg/h
d
x absolute water content of air, exhaust air in kg/kg
ABL dry air
x absolute water content of air, exhaust air in kg/kg
ZUL dry air
ρ density in kg/m
&
∆V difference in air volume flows in m /h
AHU Air handling units
5 Objectives of kitchen ventilation
Ventilation and air conditioning systems are necessary in commercial kitchens because
 the air is polluted by odours, particles of fat and gaseous products of combustion;
 indoor air quality requirements shall be met with regard to peoples health, hygiene and comfort;
 heat is created to a considerable extent due to convection and radiation;
 moisture is created by the preparation of meals and by washing;
 it is necessary to renew the air in the rooms by an exchange with outside air and maintain comfortable or
specified room air temperatures.
To meet these tasks, supply and exhaust air systems shall be installed in the kitchen areas. They should
ensure that odours, air pollutants and moisture are drawn off, impairment of rooms not forming part of the
kitchen area are avoided and no air which could be considered unhygienic is either supplied or can flow back.
Particular attention is to be paid to separate odours, particles of fat and gaseous products from the exhaust
air.
6 Classification of kitchens
Kitchens are classified according to the following features:
 spatial arrangement of appliances;
 types of meal preparation;
 number of portions to be prepared within the time limit;
 variety of meals to be prepared;
 work sequence;
 assignment of individual rooms with the kitchen area and the kitchen area itself to the meal dispatched
point.
Table A2 in Annex A shows the classification of kitchens.
The following are possible ways of connecting the kitchen to the meal dispatched point:
 kitchens with a directly-connected meal dispatched point to the dining room;
 kitchens with a separately-arranged meal dispatched point or with a distribution kitchen;
 kitchens within dining areas without a spatial separation, e.g. snack bars etc.
There are zones within kitchens which may be subject to special hygiene requirements. These are for
example.
 cold areas;
 hot areas;
 meat preparation areas;
 fish preparation areas;
 meal dispatched areas.
7 Basic design principles
7.1 General
Typical kitchen equipment emitting critical air pollution
 table top deep fat fryer;
 standard deep fat fryers;
 double deep fat fryers;
 large deep fat fryers;
 fat baking devices;
 conveyer fryer;
 tilting frying pans;
 automatic units for grilling;
 wok;
 tilting frying pans;
 frying and grilling appliance;
 griddle plate;
 lava stone-grill;
 gas heated range;
 rotisserie, gas heated;
 dishwashing machines.
Kitchens with kitchen equipment as well as kitchens with a nominal power supply in excess of 25 KW shall
have exhaust and supply air. All other kitchens shall have at least an exhaust air system.
The following data and facts must be known for the design and operation of ventilation and air conditioning
systems for kitchens:
 type of kitchen;
 number of portions to be prepared per time unit;
 operating time;
 room geometry;
 physical data for the individual building components;
 type and intensity of lighting.
Details of the following are also necessary:
 type of appliances and connected loads;
 installation and dimensions of appliances;
 duty times;
 simultaneity of appliance utilisation.
To minimise the necessary airflows, it is useful to install heat-emitting appliances in continuous blocks or
along surfaces forming room boundaries.
If the exhaust air comes into direct contact with the structure of the building, it is need to ensure that this does
not damage the building structure and that no persistent condensation occurs.
7.2 Heat and substance loads
Areas with different pollution loads may well within kitchens. The total heat emission takes place directly due
to convection radiation and latently is due to the generation of steam and other gaseous components.
Radiation-intensive areas are characterised by high surface temperatures. These include preparation areas
with grills and salamanders, grill plates, tipping frying pans, stoves, etc.
The direct and latent heat relative to the connected load of the appliances as well as the emission of steam
are given for individual appliances in table A1 of Annex A for normal operation and limited operation. The
values given in Annex A, table A3 and table A4, apply to dishwashers.
Pollution levels due to foreign substances in the air and micro-organisms may be given in national regulation
or guidelines.
Foreign substances in the air occur almost any time food is heated. The type and amount are influenced
particularly by the amount of fat and the temperature, with the ensuing pyrolyzates being possibly damaging to
health. These particularly include short-chain aldehydes, such as formaldehyde, acetaldehyde, tr-2 hexenal
and acrolein as well as highly-volatile nitrosamines and polycyclic aromatic hydrocarbons
(e.g. benzo-a-pyrene).
7.3 Further notes
To achieve a cost-effective design of the ventilation and air conditioning systems, the values in Annex A,
table A1, shall be used.
It may be necessary to cool the inlet air where there are high heat loads or for reasons of hygiene. Partitions
between individual preparation areas in kitchens may be necessary particularly for areas requiring different
levels of temperature or hygiene.
8 Ergonomic and hygiene requirements
8.1 Thermal comfort, tolerance
For the following it is assumed that kitchen personnel wear clothing with an average clothing insulation
corresponding to 0,6 clo. This value is used for the relevant comfort parameters according to EN ISO 7730
(humidity, air movement, radiation, temperature) given in figure 1.
Legend
X Wet bulb temperature in °C
Y Air temperature in °C
a Relative humidity in %
1 Workplace Range
Figure 1 — Air quality range in kitchens according to EN ISO 7730
Air temperature and humidity are measured at a height of 1,10 m above the floor at a distance of 0,50 m from
the appliances.
It is not always possible to maintain thermal comfort in kitchens. This applies particularly to work areas close
to kitchen appliances which are strong heat emitters (latent and direct heat), e.g. within a distance of
approximately 1 m of stoves with heat-radiating surfaces, tilting frying pans, large fryers or dishwashers. In
these areas, tolerable climatic conditions according to EN ISO 7730 should be guaranteed as a minimum.
NOTE If too many heat-emitting cooking appliances are installed in a room which is not sufficiently large enough for
the purpose, it may not be possible to meet the ergonomic requirements for ventilating and air conditioning systems.
Draughts due to higher airflow velocities may occur, particularly where there are supply airflows in excess of
3 2
90 m /(m h).
8.2 Temperature of room air
The temperature of the room air in kitchens and sculleries should be at least 18 °C and should not exceed
26 °C unless unavoidable due to the processes. This does not include brief, seasonal, excess temperatures or
areas in which higher temperatures are unavoidable due to their function.
Cooling of the room air is recommended for good thermal comfort and is required by some national
regulations or guidelines.
8.3 Humidity of room air
The relative humidity in the occupied zone shall not exceed the values given in table 1.
Table 1 — Relative humidity in the occupied zone
Room air temperature Room humidity
in °C in %
20 80
22 70
24 62
26 55
In comfort areas, the upper limit of the moisture content of the air is 11,5 g of water per kg of dry air and 65 %
relative humidity.
Because comfortable climatic conditions may not always be achieved in kitchens, the design of a ventilation
and air conditioning system may be based on a maximum moisture content x of the air of 16,5 g of water per
kg of dry air.
No reliable data is available regarding the lower limit of the relative humidity of the room air. 30 % relative
humidity of the room air may be taken as the comfort limit – as independent as possible from the temperature
of the room air – with occasional undershoots being acceptable.
8.4 Air velocity in the room
The limits of the air velocity in the comfort area depend on the temperature of the room air, the turbulence of
the flow, the degree of activity and the thermal resistance of the clothing according to EN ISO 7730.
The limiting values given in EN ISO 7730, example curve shown in figure 2 for 0,6 clo should not be
exceeded. Measurements are generally carried out at the workstation at a height of 1,7 m.
Legend
X Temperature of room air in °C
Y Permissible mean air velocity in m/s
1 Degree of activity 2
Figure 2 — Example of permissible mean room air velocity as a function of the room air temperature
for 0,6 clo
8.5 Noise control
If no national requirements are given, the A-weighted sound pressure level emitted by a ventilation and air-
conditioning system, may be limited to 50 dB(A) to 60 dB(A). Where the meals are handed out from an open
counter, the A-weighted sound pressure level may not exceed 50 dB(A). Exceeding this value by 5 dB(A) is
permissible in areas where tableware and utensils are washed.
Sound levels and flows should be optimised when designing ventilation and air conditioning systems,
particularly with a view to minimising the use of sound absorbing measures in the exhaust air. This also
means that the sound power level of the extraction fan will be minimised. Sound-absorbing surfaces can also
be used in the room as additional sound insulation, but this must be consistent with other requirements e.g.
hygiene. The ventilation and air conditioning system should not lead to sound pressure levels in other parts of
the building which would not respect national regulation or guidance or EN 15251.
8.6 Hygiene requirements
From the point of view of hygiene, the task of a ventilation and air conditioning system for kitchens is also to
prevent the contamination of food by the airflow during preparation, storage and distribution and to prevent an
undefined spread of odours, pollutants and other gaseous substances by the airflow.
National hygiene regulations shall always be fulfilled.
To meet these tasks, hygiene requirements may be set for individual components, system concepts and
maintenance. If different levels of hygiene requirements are required for different areas of the kitchen, this can
be done by appropriate airflows transfer in the room.
All airflows (supply and exhaust air) from all kitchen zones should be balanced over the entire kitchen area.
A slight underpressure should be maintained in the kitchen in order to avoid odours spreading from the
kitchen. When this is done, however, the recirculation of air from rooms where the hygiene is questionable
shall be precluded.
Ventilation and air conditioning systems may be operated using external air only. Recirculated air should not
be used.
Hygiene requirements shall be jointly agreed with the kitchen designer, the operator and, where necessary,
the supervisory authorities.
9 Air circulation within the room
9.1 Basic types of airflow
The supply air of ventilation and air conditioning systems may be distributed within the room so that flow
patterns are controlled. A distinction is made, depending on the type of load reduction, in air conditioning
between two basic flow patterns, i.e. mixed flow and laminar flow which is also frequently referred to as source
ventilation.
9.2 Mixed flow
The clean supply air and the air around the cooking appliances enriched by foreign substances mix
completely. The polluted room air is diluted by external air and therefore the same temperatures and
substance concentrations are reached almost throughout the kitchen. The intensive mixing is achieved by
supply airstreams with a relatively high impulse which, to meet the climatic-physiological requirements, should
settle down above the human occupation zone.
Different possible designs:
Horizontal air supply
Where air is supplied horizontally underneath the ceiling of the room, with radial jet. These can deflect
thermal plumes at cooking appliances into the work area and extraction flows for extraction devices
mounted above the kitchen appliances may be disturbed. Ventilation grids or air nozzles are used as air
inlets.
Vertical air supply
A mixed flow can also be achieved by several conical airstreams from the ceiling of the room, whereby
the inlets are distributed on the ceiling. A mixing and induction area forms around each air inlet.
By arranging the outlets above the cooking and work areas, the disturbance of thermal plumes can be
reduced.
Jet, swirl, circular/square ceiling diffusers and linear air inlets are used for these forms of flow.
9.3 Laminar flow (displacement)
Laminar flows reduce the pollution in the area occupied by people both with regard to thermal and substance
pollution.
With this type of air supply, the room airflow is characterised by the thermal plumes generated at the cooking
appliances, which conveys the heated air, enriched by foreign substances, from the cooking area upwards
from where it is drawn off by suitable extraction devices. Care should be taken to ensure that pulsing of the air
supply is minimised so that the thermal plumes remains undisturbed.
By studies it is shown, that laminar flow (displacement) is the better system of kitchen ventilation. Therefore
this system is to be preferred for significant air quality improvement.
Different possible designs
Ceiling-mounted air terminals
(displacement air terminals)
Where there is very low-impulse air supply through large-area air inlets outside the influence area of the
thermal plumes, it is possible for the supply air to pass down from the room ceiling to the occupied area.
The colder supply area flows to the ground because of its higher specific weight and replaces the thermally
driven airflow.
Provided the thermal plume generated at the cooking appliances is not disturbed, a significantly reduced
substance and heat pollution results compared with the mixed. The reduction of pollution, assuming the same
volumetric flows, are significantly better than by mixed flow.
Any cross currents which occur, due to an unsatisfactory arrangement of the air inlets, can disturb the thermal
plumes and lead to flush out and therefore to increase in the room pollution.
The load reduction is limited by the fact that the supply air initially passes through more or less polluted areas
and a proportion of the polluted room air is transported to the occupied area by induction and mixing.
The supply air should be applied uniformly to the large-area air inlets so that constriction of the jet is
minimised. The air velocity in the occupied zone shall not exceed 0,2 m/s.
Air inlets in the occupied zone
(displacement air supply terminals)
Where a laminar flow is consistently used, air terminals shall be installed at heights between 0,2 m and
2,0 m above the floor in such a way that the supply air replaces the thermal airflow without causing a
disturbance. This requires that the airflow into the air inlets be equally distributed, the air outlet velocity
≤ 0,4 m/s (near zone) for cylindrical and 0,2 m/s for flat air inlets (in each case relative to the inlet air
area) and that the supply air temperature does not fall below 20 °C.
Air terminals shall be arranged in such a way that the air is distributed as uniformly as possible over the room
areas and is assigned to the thermally induced airflow; where they are round they can be placed anywhere in
the room or installed surface-mounted or flush on walls as flat, semi-cylindrical or cylindrical outlets.
The outlet elements must be accessible and designed for ease of cleaning.
Where the air inlets are arranged in the occupied area and the airflows are correctly dimensioned, load
reductions are significantly better than by mixed flow with the same supply airflow.
The fact that arranging the air inlets in the occupied areas enables higher load reductions than if laminar air
inlets are fitted in the ceiling is because where the air enters through the ceiling it first flows through heavily-
polluted areas of the room and during its passage down to the occupied area a proportion of the polluted room
air is mixed with the supply airstream and carried down into the occupied zone.
10 Design principles
10.1 General
The main design variables for air conditioning equipment in kitchens are as follows.
 Extraction airflows through kitchen hoods;
 supply airflows;
 room exhaust airflows (general ventilation).
It is recommended to have a general exhaust in the kitchen in order to deal with thermal loads and humidity
(lighting, occupants, hot meals, equipments not under hoods, insufficient capture of the heat plumes). If the
kitchen is air conditioned, these parameters are necessary to calculate the cooling capacity.
The extraction airflow shall be designed to provide the maximum possible substance extraction above the
cooking point.
The supply airflow shall be designed according to the heat or substance loads to be carried from the work
area so that the substance limit values and the requirements regarding the thermal environment are met.
The room exhaust airflow is the difference between the supply airflow and the airflow into the extraction
device.
To prevent the potential transfer of kitchen odours to areas outside the kitchen, a slight underpressure in the
kitchen is recommended. A minimum of 3 % higher exhaust air than the supply air is recommended.
It shall be ensured that unfiltrated air cannot come in an undefined way into the kitchen.
Take care that all doors shall be operable in order to facilitate escape regardless of underpressure.
The values in table A1 for normal operation may be used as a basis for dimensioning the airflows. Normal
operation is presumed to be an economical method of operation. Separate agreements are to be reached
where the use of equipment deviates from this (e.g. cooking with cooker lid open).
The values for restricted operation are used for calculating the part load.
Examples of airflow calculation are given in Annex B.
10.2 Pre-dimensioning
10.2.1 General
The following pre-dimensioning methods are not capable to replace a detailed calculation taking into account
the detailed kitchen appliances installed. Even the dimensioning of ductwork is not possible in detail on basis
of this pre-dimensioning.
10.2.2 Hourly air replacement method based on the kitchen size
When no information relating to the equipment is available, a rough dimensioning can be made in accordance
with table 2, but it should only be used for estimation in the initial planning stage. In each case, a detailed
calculation in accordance with clause 10.3 shall be carried out during implementation planning.
Table 2 — Hourly air replacement method
Type of kitchen Air volume factor (default value)
Overall kitchen 90 m³/h per m² kitchen area
bakery / dishwashing area 120 m³/h per m² kitchen area
10.2.3 Method based on the capture velocity
If there is some additional information available relating to the kitchen appliances, the following method should
be used in calculating the flow rate on the basis of the airflow velocity (v) in the free space between the hood
bottom part and the cooking appliances. This method allows a check that the final dimensioning will be
compatible with the room volume (upper than 50 ACH, air diffusion is difficult to obtain satisfactory residual
velocities).
It is considered that for velocities ranging from 0,20 to 0,50 m/s, depending on the type of appliance, particle
removal is correct (e.g. 0,20 m/s for boiling pans; 0,50 m/s for deep fat fryers).
q =v ×3600×P × ∆h (1)
v−ext
10.2.4 Guide values for ancillary rooms
Guide values for ancillary rooms are given in table 3.
Table 3 — Guide values for ancillary rooms
Area Volumetric airflow
3 2
in m /(m h)
Meat preparation 25
Fish preparation 25
Poultry preparation 25
Vegetable preparation 25
Dry store 6
Bread store 6
Non-food store 6
a
Room occupied by personnel 10
a
Personnel changing room/WC/shower

Empties store 6
Hot meal delivery point 60
a
National regulations for Workplaces shall be observed
10.3 Dimensioning - detailed method
10.3.1 Thermally induced airflow
A free convection plume forms above kitchen appliances due to differences in temperature or density. The
&
flow pattern is determined by the convectively transmitted proportion of the direct heat load Q of the kitchen
S,K
appliances.
The convective share shall be calculated according to equation (2) using the values for the direct heat
emission at the appliances given by the manufacturer or in table A1:
& &
Q = P×Q ×b (2)
S,K S
&
The thermally induced airflow V , also referred to as the warm airflow, may be regarded as a non-isothermal
th
free stream above the cooking point which induces air from the environment. It depends on the distance
covered by the airflow, z. This calculation shall be done for each appliances.
1/3 5/3
& &
V = k ×(Q ×ϕ) ×(z +d ) ×r (3)
th S,K hydr
4/3 −1/3 −1
k =18m W h (4)
B
d = 2×L× (5)
hydr
L +B
Table 4 — Reduction factors for thermally induced airflows
Arrangement of heat source Reduction factor r
Installed anywhere 1,00
Installed against the wall 0,63
Values for the simultaneity factor φ are given in Table A2.
Thermally inactive areas within a kitchen area shall be included in the calculation of the hydraulic diameter.
Frontal working areas without thermal loads need not be included.
For heat-emitting kitchen appliances installed against wall surfaces, the thermal plume lies against the wall
surface and forms an airstream along the wall. The airflow induced into this wall stream is lower than in the
free stream. This effect is given in ratio r (table 4).
10.3.2 Extraction airflows for kitchen extraction hoods
If the exhaust air is removed from the room through extraction hoods, the extraction airflow results from the
thermal flow at the lower edge of the extraction device, in accordance with Equation (6) and figure 3.

Legend
1 Induction air
&
2 Thermic airflow V in m /h
th
3 Extraction airflow
4 Kitchen extraction hood
5 Kitchen appliance
B Width in m
L Length in m
h Height of appliance in m
z Height above the heat source in m
Figure 3 — Schematic representation of the extraction of the thermally induced airflow
Disturbances to the thermal flow may lead to flush out the plumes from the hood. Therefore a correction
coefficient depending on the supply and air diffusion is used to increase the extraction designed in order to
improve containment.
& &
V =V ×a (6)
Erf th
Values for the correction coefficient for flush-out are given in table 5. This coefficient integrates the influence
of the various velocities and turbulences in the kitchen.
Table 5 — Guide values for the correction coefficient for flush-out
Type of flow Degree of flush-out for kitchen extraction hoods and
kitchen extraction ceilings
Mixed flow
Radial ATD (air terminal device)
1,25
Plane or tangential ATD
1,20
Laminar flow
Displacement ATD ceiling
1,10
Displacement ATD wall
1,05
An airflow below the calculated value is possible if the manufacturer can show according to part 9 of this
EN-series, that the hood is working proper at an airflow of the factor e below calculated necessary airflow. If
eff
a test is carried out according to part 9 of this EN-series, formula 6 can be replaced by formula 6a.
& &
V =V ×a×e (6a)
Erf th eff
10.3.3 Exhaust airflows in connection with kitchen extraction hoods
The exhaust airflow from the kitchen is calculated from the total extraction airflows at the kitchen extraction
&
hoods or other extraction devices, in accordance with Equation (6a), and from the total airflow V moved by
th,ne
the thermal up to a height above the floor H of 2,5 m, in accordance with Equation (3), for the heat sources
which are not underneath the hoods. This airflow is to be drawn off at the room ceiling.
For heat sources not situated directly below the hoods, disturbances to the airflow by the supply air system
are also taken into account by the correction of flush-out given in table 5.
NOTE If there is no general ventilation, this addition airflow can be added to the hood airflow. This is not
recommended, especially if this airflow becomes higher than 10 % of the overall exhaust airflow in the kitchen.
We therefore get:
n
& & &
V = V +V ×a (8)
ABL ∑ Erf th,ne
i=1
n
& & &
V +V ≥ 0,1 V (9)
th,ne Ausgl ∑ Erf
i=1
10.3.4 Exhaust airflows in connection with kitchen air extraction ceilings
10.3.4.1 General case
If all previous chapters don’t apply to ceilings, this should be clarified.
The necessary exhaust airflow is calculated from the airflow moved by the thermal plume up to a height H of
2,5 m above the floor (ceiling height), in accordance with Equation (4).
Disturbances to the airflows by the supply air system are taken into account by the amount of flush-out a.
Table 5 gives guide values.
n
 
& &
V =a V (10)
∑ 
ABL th
j =1
 
10.3.4.2 Case of ceilings with integrated air supply
Kitchen extraction ceilings with integrated air supply are to be dealt with according to 10.3.3.
10.3.5 Check calculation
Regardless of the type of exhaust air extraction, a check calculation in accordance with Equation (11) is to be
carried out for every extraction device to protect against condensation:
m
&
m ×ϕ
∑ d
j=1
&
V = (11)
ABL
()x −x × ρ
ABL ZUL
ρ = 1,2 kg/m ;
()χ − χ = 6 g/kg dry air;
ABL ZUL
however: χ ≤ 16,5 g/kg dry air.
ABL
The largest exhaust airflow is chosen in each case.
Where the latent component as per Equation (11) in cooking processes is greater than the sensitive
component as per Equation 6, the difference in air volume flows
&
∆V =()Eq()11 −Eq(6) (7)
can be delivered directly into the hood. In this case, e Equation (6a) is reduced by this amount, or e can be
eff eff
&
chosen so as to equal ∆V .
10.3.6 Supply airflows
If possible, the kitchen shall remain at a slightly lower pressure than the guest room in order to avoid air
overspill. However, the exhaust air volume rate shall not exceed the supply air volume rate by more than 3 %
to 5 %.
11 Ventilation and air conditioning systems
11.1 Exhaust air systems
Exhaust air systems in kitchens extract, transport and emit polluted room air as well as odours to the outside
atmosphere. Exhaust air systems are therefore designed in such a way that undesirable components in the air
are separated with efficient air extraction in order to maintain the permissible emission values.
For reasons of hygiene and energy, it may be appropriate to divide the exhaust air volumetric flows amongst
different systems.
The exhaust air from the areas for boiling, cooking, roasting, vegetable and meat preparation as well as for
meal distribution can be brought together in a common exhaust air system by exploiting different utilisation
times. This also applies to other rooms such as stores, recreation rooms, occupied rooms and supply and
disposal areas provided this can be achieved while still maintaining appropriate fire zones.
The steam created by dishwashers and the mechanically-generated dishwasher exhaust air (sometimes
chemically polluted) should be collected and, if possible separately, extracted immediately at the point at
where it occurs. Pressure fluctuations which can occur due to dishwasher blowers being switched on and off
a
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