EN-15251-standard.pdf

Document type: European Standard Document subtype: Document stage: committee draft Document language STD Version 2.1c

CEN/TC 156 Date: 2014-08-20

prEN 15251

CEN/TC 156WG19-N77

Secretariat: BSI

Indoor environmental input parameters for the design and assessment of energy performance of buildings.

Tm standardiluonnos on siin muodossa kuin se lhtee kansallisille lausunnoille syksyll 2014 lukuunottamatta editointia

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Contents Page

Indoor environmental input parameters for the design and assessment of energy performance of buildings. ............................................................................................................................................... 1

1 Scope...................................................................................................................................................... 5

2 Normative references ........................................................................................................................... 6

3 Terms and definitions ........................................................................................................................... 8

4 Symbols and abbreviations ............................................................................................................... 10

5 Interactions with other standards ..................................................................................................... 11

6 Design input criteria for dimensioning of buildings, heating, cooling, ventilation and lighting systems .................................................................................................................................. 13

6.1 Thermal environment .......................................................................................................................... 13 6.1.1 Mechanically heated and/or cooled buildings ................................................................................. 13 6.1.2 Buildings without mechanical cooling ............................................................................................. 14 6.2 Design for Indoor air quality (ventilation rates) ............................................................................... 14 6.2.1 General ................................................................................................................................................. 14 6.2.2 Methods ............................................................................................................................................... 15 6.2.3 Non-residential buildings ................................................................................................................... 17 6.2.4 Residential buildings .......................................................................................................................... 17 6.2.5 Access to operable windows ............................................................................................................. 18 6.2.6 Filtration and air cleaning .................................................................................................................. 18 6.3 Humidity ............................................................................................................................................... 18 6.4 Lighting ................................................................................................................................................ 18 6.4.1 General ................................................................................................................................................. 18 6.4.2 Non-residential buildings ................................................................................................................... 18 6.4.3 Residential buildings .......................................................................................................................... 19 6.5 Noise..................................................................................................................................................... 19

7 Indoor environment parameters for energy calculation ................................................................. 19 7.1 Thermal environment .......................................................................................................................... 20 7.1.1 Seasonal calculations......................................................................................................................... 20 7.1.2 Hourly calculations (dynamic simulation) ........................................................................................ 20 7.2 Indoor air quality and ventilation ...................................................................................................... 20 7.2.1 General ................................................................................................................................................. 20 7.2.2 Non-residential buildings ................................................................................................................... 20 7.2.3 Residential buildings .......................................................................................................................... 21 7.3 Humidity ............................................................................................................................................... 21 7.4 Lighting ................................................................................................................................................ 21 7.4.1 Non-residential buildings ................................................................................................................... 21 7.4.2 Residential buildings .......................................................................................................................... 21

Annex A1 (normative) Recommended criteria for the thermal environment ........................................... 22 A1.1 Recommended categories for mechanically heated and cooled buildings .................................. 22 A1.2 Acceptable indoor temperatures of buildings without mechanical cooling systems. ............... 26 A1.3 Increased air velocity .............................................................................................................................. 28 A1.4 Recommended indoor temperatures for energy calculations........................................................ 29

Annex A2 (normative) Basis for the criteria for indoor air quality and ventilation rates ........................... 30 A2.1 Design ventilation air flow rates ............................................................................................................ 30 A2.1.1 General .................................................................................................................................................. 30 A2.1.2 METHOD 1 - Method based on perceived air quality ........................................................................ 30 A2.1.3 METHOD 2 - Method using limit values of gas concentration ......................................................... 32

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A2.1.4 Ventilation air flow rates for residential buildings ............................................................................ 32 A2.1.5 Ventilation air flow rate during unoccupied periods ........................................................................ 34 A2.2 The Recommended criteria for dimensioning of humidification and de-humidification ................. 35

Annex A3 (normative) Example on how to define low and very low polluting buildings ......................... 36

Annex A4 (normative) Examples of criteria for lighting ............................................................................. 37

Annex A5 (normative) Indoor system noise criteria of some spaces and buildings .............................. 38

Annex A6 (informative) WHO health-based criteria for indoor air .............................................................. 40

Annex A7 (informative) Occupant schedules for energy calculations ....................................................... 42

Annex B1 (informative) Recommended criteria for the thermal environment ......................................... 52 B1.1 Recommended categories for mechanically heated and cooled buildings .................................. 52 B1.2 Acceptable indoor temperatures of buildings without mechanical cooling systems. ............... 56 B1.3 Increased air velocity .............................................................................................................................. 58 B1.4 Recommended indoor temperatures for energy calculations........................................................ 59

Annex B2 (informative) Basis for the criteria for indoor air quality and ventilation rates ......................... 60 B2.1 Design ventilation air flow rates ............................................................................................................ 60 B2.1.1 General .................................................................................................................................................. 60 B2.1.2 METHOD 1 - Method based on perceived air quality ........................................................................ 60 B2.1.3 METHOD 2 - Method using limit values of gas concentration ......................................................... 62 B2.1.4 Ventilation air flow rates for residential buildings ............................................................................ 62 B2.1.5 Ventilation air flow rate during unoccupied periods ........................................................................ 64 B2.2 The Recommended criteria for dimensioning of humidification and de-humidification ................. 65

Annex B3 (informative) Example on how to define low and very low polluting buildings ....................... 66

Annex B4 (informative) Examples of criteria for lighting ........................................................................... 67

Annex B5 (informative) Indoor system noise criteria of some spaces and buildings ............................ 68

Annex B6 (informative) WHO health-based criteria for indoor air .............................................................. 70

Annex B7 (informative) Occupants schedules for energy calculations ..................................................... 72

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Foreword

This document NWI EN 15251rev has been prepared by Technical Committee CEN/TC 156 Ventilation for Buildings, the secretariat of which is held by BSI.

This document is currently a draft for the working group.

This document has been prepared under a mandate 480 given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive 2002/91/EC and recast.

CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden Switzerland and United Kingdom. Plus, plus, plus, plus++++++++++

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Introduction

Energy consumption of buildings depends significantly on the criteria used for the indoor environment (heating, cooling, ventilation and lighting) and building (including systems) design and operation. Indoor environment also affects health, productivity and comfort of the occupants. Recent studies have shown that costs of poor indoor environment for the employer, the building owner and for society, as a whole are often considerable higher than the cost of the energy used in the same building. It has also been shown that good indoor environmental quality can improve overall work and learning performance and reduce absenteeism. In addition uncomfortable occupants are likely to take actions to make themselves comfortable which may have energy implications. There is therefore a need for specifying criteria for the indoor environment for design and energy calculations for buildings and building service systems.

The present standard is a revision of EN15251-2007. There exist other national and international standards, and technical reports, which specify criteria for thermal comfort and indoor air quality (EN ISO 7730, CR1752). These documents do specify different types and categories of criteria, which may have a significant influence on the energy demand. For the thermal environment criteria for the heating season (cold/winter) and cooling season (warm/summer) are listed. These criteria are, however, mainly for dimensioning of building, heating, cooling and ventilation systems. They may not be used directly for energy calculations and year-round evaluation of the indoor thermal environment. Studies have shown that occupant expectations in natural ventilated buildings may differ from conditioned buildings, which will be part of this standard

The present standard specifies how design criteria shall be established and used for dimensioning of systems. It defines how to establish and define the main parameters to be used as input for building energy calculation and short and long term evaluation of the indoor environment. Finally this standard will identify parameters to be used for monitoring and displaying of the indoor environment as recommended in the Energy Performance of Buildings Directive.

Different categories of criteria may be used depending on type of building, type of occupants, type of climate and national conditions. The Standard specifies several different categories of indoor environment which could be selected for the space to be conditioned. These different categories can be used for design and may also be used to give an overall, yearly evaluation of the indoor environment by evaluating the percentage of time in each category.

1 Scope

This European Standard deals with the indoor environmental parameters for thermal environment, indoor air quality, lighting and acoustic.

This standard specifies how to establish indoor environmental input parameters for building system design and energy performance calculations.

This standard includes design criteria for the local thermal discomfort factors. draught, radiant temperature asymmetry, vertical air temperature differences, floor surface temperature.

This standard is applicable where the criteria for indoor environment are set by human occupancy and where the production or process does not have a major impact on indoor environment.

This standard specifies occupancy schedules to be used in standard energy calculations.

This standard specifies how different categories of criteria for the indoor environment can be used. But does not require certain criteria to be used. This is up to national regulations or individual project specifications.

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The criteria in this standard can also be used in national calculation methods. This standard sets criteria for the indoor environment based on existing standards and reports listed under normative references or in the bibliography.

The standard does not prescribe design methods, but give input parameters to the design of buildings, heating, cooling, ventilation and lighting systems

2 Normative references

This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies.

EN ISO 7726 Ergonomics of the thermal environment Instruments for measuring physical quantities

EN ISO 7730 Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort

EN ISO 8996 Ergonomics Determination of metabolic heat production

EN ISO 9920 Ergonomics of the thermal environment estimation of the thermal insulation and evaporative resistance of a clothing ensemble

EN ISO 13731 Ergonomics of the thermal environment - Definitions, symbols and units.

EN ISO 13790 Thermal performance of buildings Calculation of energy use for space heating and cooling Simplified method

EN ISO 13791 Thermal Performance of Buildings Calculation of Internal Temperatures in a Room in Summer without Mechanical Cooling General Criteria and Validation Procedures

EN ISO 13792 Thermal performance of buildings Internal temperature of a room in summer without mechanical cooling Simplified calculation methods

EN 12193 Light and lighting Sports Lighting

EN 12792 Ventilation for Buildings Symbols, Terminology and Graphical Symbols

EN12831 Heating systems in buildings-Calculation of the heating load

EN 12464-1 Light and lighting Lighting of work places- Part 1: Indoor work places

EN12599 Ventilation for buildings Test procedures and measuring methods for handing over installed ventilation and air conditioning systems

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EN 12665 Light and Lighting Basic terms and criteria for specifying data of lamps and luminaries

EN 13032-1

EN 13141 parts 1-11

Light and lighting Measurement and presentation of photometric data of lamps and luminaries

Ventilation for buildings - Performance testing of components/products for residential ventilation

EN13779

En 13142

Ventilation for non-residential buildings - performance requirements for ventilation and room-conditioning systems

Ventilation for buildings - Components/products for residential ventilation - Required and optional performance characteristics

PrEN14788

prEN 15193-1

Ventilation for buildings Design and dimensioning of residential ventilation systems

Energy performance of buildings - Energy requirements for lighting

EN15203 Energy performance of buildings Assessment of energy use and definition of ratings

EN 15217 Energy performance of buildings Methods for expressing energy performance and for energy certification of buildings

EN 15239 Ventilation for buildings Calculation methods for the determination of air flow rates in buildings including infiltration

EN 15240 Energy performance of buildings Guidelines for the inspection of air-conditioning systems

EN15241 Ventilation for buildings Energy performance of buildings Guidelines for the inspection of ventilation systems

EN15242 Ventilation for buildings Calculation methods for the determination of air flow rates in buildings including infiltration

EN 15243 Dynamic calculation of room temperatures and of load and energy for buildings with room conditioning systems (including solar shading, passive cooling, position and orientation

EN 15255 Thermal performance of buildings Sensible room cooling load calculation General criteria and validation procedures

EN 15265 Energy performance of buildings Calculation of energy use for space heating and cooling General criteria and validation procedures

EN 15378 Energy performance of buildings Systems and methods for the inspection of boilers and heating systems

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ISO 15927-4

EN 15665

Hygrothermal performance of buildings-Calculation and presentation of climatic data Part 4: Data for assessing the annual energy for cooling and heating systems and Part 5: Winter external temperatures and related wind data

Ventilation for buildings - Determining performance criteria for residential ventilation systems

ISO/TS14415 The Application of International Standards for People with Special Requirements

CR 1752 2001 Ventilation for buildings Design criteria for the indoor environment

CIE 69 1987 Methods for characterizing illuminance meters and luminance meters: Performance, characteristics and specifications

3 Terms and definitions

For the general purposes of this European Standard, the terms and definitions given in EN 12792, EN ISO 13731 and EN 12464, EN12665 and EN15603 shall apply.

3.1 Adaptability, thermal Physiological, psychological or behavioural adjustment of building occupants to the interior thermal environment in order to avoid or to limit thermal discomfort. In naturally ventilated buildings these are often in response to changes in indoor environment induced by outside weather conditions.

3.1.1 Adaptation, Perceived Air Quality Sensory adaptation to perceived air quality (odour), which occurs during the first 15 min. exposure to bioeffluents.

3.2 Active cooling

See mechanical cooling.

3.4 Buildings, Very Low-Polluting A building where predominantly low-emitting materials and furniture are used and activities with emission of pollutants are prohibited and no previous emitting sources (like tobacco smoke) was present. Criteria are listed in Annex B3.

3.5 Buildings, Low-Polluting Buildings where an effort has been done to select low-emitting materials and activities with emission of pollutants are limited or prohibited. Criteria are listed in Annex B3.

3.6 Buildings, not Low-Polluting Old or new buildings where no effort has been done to select low-emitting materials and activities with emission of pollutants not prohibited. Previous emissions (like tobacco smoke) may have taken place.

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3.7 Buildings without mechanical cooling

Buildings that do not have any mechanical cooling and rely on other techniques to reduce high indoor temperature during the warm season like moderately-sized windows, adequate sun shielding, use of building mass, natural ventilation, night time ventilation etc. for preventing overheating.

3.8 Cooling season Parts of the year during which (usually summer), at least parts of the day and part (some rooms) of the building, cooling are needed to keep the indoor temperatures at specified levels.

Note: The length of the cooling season differs substantially from country to country and from region to region).

3.9 Daylight factor Ratio of the illuminance at a point on a given plane due to the light received directly or indirectly from a sky of assumed or known luminance distribution, to the illuminance on a horizontal plane due to an unobstructed hemisphere of this sky, excluding the contribution of direct sunlight to both illuminances. [EN 12665:2011]

3.10 Demand controlled ventilation A ventilation system where the ventilation rate is controlled by air quality, moisture, occupancy or some other indicator for the need of ventilation.

3.11 External temperatures, daily mean The average of the hourly mean external air temperature for one calendar day (24 hours)

3.12

External temperature, running mean

The exponentially weighted running mean of the daily mean external air temperature ed

3.13 Heating season Parts of the year during which (at least parts of the day and part of (some rooms) the building,) heating appliances are needed to keep the indoor temperatures at specified levels. Note: The length of the heating season differs substantially from country to country and from region to region).

3.14 Mechanical cooling Cooling of the indoor environment by mechanical means used to provide cooling of supply air, fan coil units, cooled surfaces, etc. Note: The definition is related to peoples expectation regarding the internal temperature in warm seasons. Opening of windows during day and night time is not regarded as mechanical cooling.

3.15 Optimal operative temperature

The operative temperature that satisfies the greatest possible number of people at a given clothing

and activity level with the thermal environment. 3.15a

Operative temperature

The uniform temperature of an imaginary black enclosure in which an occupant would exchange the

same amount of heat by radiation plus convection as in the actual non-uniform environment

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3.16 Occupied hours The occupied hours of the building are those when the majority of the building is in its intended use. 3.17 Room Conditioning System A system installed and used to keep a comfort conditions in a room within a defined range. Air conditioning as well radiant, surface heating and cooling systems are included.

3.18 Ventilation rate

The magnitude of outdoor air flow to a room or building through the ventilation system and infiltration through building envelope.

3.19 Ventilation system A combination of appliances designed to supply indoor spaces with outdoor air and to extract polluted indoor air. Ventilation system refers to mechanical, natural and hybrid ventilation systems.

3.20 Design ventilation airflow rate Ventilation rate that the system shall be able to provide (including boost).

4 Symbols and abbreviations

o = indoor operative temperature, oC

e = external temperature, oC

rm-i = Running mean external temperature for i previous day

ed-i = daily mean external temperature for the iprevious day

= constant between 0 and 1. Recommended to use 0,8

qtot= total ventilation rate, l/s

qB= ventilation rate for building materials, l/(sm2)

qp= ventilation rate for persons, l/(s,person)

n = number of persons, -

Qh = ventilation rate required for dilution, in litre per second;

Gh = pollution load of a pollutant, in micrograms per second;

Ch, = guideline value of a pollutant, in micrograms per litre;

Ch,o = supply concentration of a pollutant at air intake, in micrograms per litre;

v = ventilation effectiveness (EN13779)

A= floor area, m2

Lp,A= A-weighed sound pressure level, dB(A)

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Leq, nT,A = Equivalent Continuous Sound Level

D = Daylight factor

E = Illuminance (at a point or surface), lx

Ra = Colour rendering index

UGR = Unified Glare Rating Limit

PPD = Predicted Percentage of Dissatisfied, %

PMV = Predicted Mean Vote

DR = Draught Rate, %

Daylight factor DCa,j

Daylight factor DSNA

5 Interactions with other standards

The present standard will provide indoor environmental criteria for the design of buildings, room conditioning systems and lighting systems. The thermal criteria (PMV or design indoor temperature in winter, design indoor temperature in summer) are used as input for heating (EN12831) and cooling load (EN 15243) calculations and sizing of equipment. Ventilation rates are used for sizing ventilation systems, and lighting levels for design of lighting system including the use of day lighting (EN12464-1)

The present standard will provide values for the indoor environment (like temperature, ventilation rate, illuminance) as input to the calculation of the energy demand (building energy demand), when the space is occupied, (EN ISO 13790, EN 15255, EN 15265, EN15193) (Section 7).

Recommended input values are given for each of the different categories. A short description of the categories is shown in table 1.

Table 1: Description of the applicability of the categories used. (Table 2 can be seen on the next page)

Category

Explanation

I High level of expectation and also recommended for spaces occupied by very sensitive and fragile persons with special requirements like some disabilities, sick, very young children and elderly persons, to increase accessibility.

II Noral level of expectation

III An acceptable, moderate level of expectation

IV Low level of expectation. This category should only be accepted for a limited part of the year

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Table 2 shows the relative position of this standard within the EN EPB set of standards.

Table 2 Position of this standard within the EN EPB set of standards according to EN15603

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Technical Building Systems

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1 General

1 General

1 General

2

Common terms and definitions; symbols, units and subscripts

2

Building Energy Needs

2 Needs

3 Applications

3 (Free) Indoor

Conditions without Systems

3 Maximum Load

and Power

4 Ways to Express

Energy Performance

4 Ways to

Express Energy Performance

4 Ways to Express

Energy Performance

5

Building Functions and

Building Boundaries

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Heat Transfer by Transmission

5 Emission &

control

6

Building Occupancy and

Operating Conditions

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Heat Transfer by Infiltration

and Ventilation 6

Distribution & control

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Aggregation of Energy Services

and Energy Carriers

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Internal Heat Gains

7 Storage &

control

8 Building

Partitioning 8

Solar Heat Gains

8 Generation &

control

9 Calculated

Energy Performance

9 Building

Dynamics (thermal mass)

9

Load dispatching and

operating conditions

10 Measured

Energy Performance

10 Measured

Energy Performance

10 Measured

Energy Performance

11 Inspection

11 Inspection

11 Inspection

12 Ways to Express Indoor Comfort

12 BMS

13 External

Environment Conditions

14 Economic

Calculation

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6 Design input criteria for dimensioning of buildings, heating, cooling, ventilation and lighting systems

For design of buildings and dimensioning of room conditioning systems the thermal comfort criteria (minimum room temperature in winter, maximum room temperature in summer) shall be used as input for heating load (EN12831) and cooling load (EN15253) calculations. Ventilation rates that are used for sizing the equipment shall be specified in design (EN13779, EN15241, and EN15242). The criteria in this section shall be used as input values for the sizing and dimensioning of the systems as well as for design of buildings without mechanical cooling.

Criteria specified in national building codes for design and dimensioning of systems must be used. The present standard gives, in informative annexes, recommended input values for use in cases where no national regulation are available. The recommended criteria are given for several categories. Design criteria for the indoor environment shall be documented by the designer together with the premises for use of the spaces. .

6.1 Thermal environment

6.1.1 Mechanically heated and/or cooled buildings

For establishing design criteria the following procedure shall be used.

Criteria for the thermal environment in heated and/or cooled buildings shall be based on the thermal comfort indices PMV-PPD (predicted mean vote - predicted percentage of dissatisfied) with assumed typical levels of activity and typical values of thermal insulation for clothing (winter and summer) as described in detail in EN ISO 7730. Based on the selected criteria (see Table B1.1-1 for intended comfort category) a corresponding design operative temperature interval is established. The values for dimensioning of cooling systems are the upper values of the comfort range during cooling season (summer) and values for dimensioning of the heating system are the lower values of the comfort range. Some examples of recommended design indoor operative temperatures for heating and cooling, derived according to this principle, are presented in Annex B1.1 Table B1.1.-2 and in TR15251

The design criteria in this section shall be used for both design of buildings (dimensioning of windows, solar shading, building mass etc.) and HVAC systems.

Instead of using operative temperature as the design criterion the PMV-PPD index can be used directly. In this way the effect of increased air velocity and effect of dynamic clothing insulation can be taken into account.

Selection of the category is building specific, and the needs of special occupant groups such as elderly people (low metabolic rate and impaired control of body temperature) shall be considered (ISO/TS14415). For this group of people it is recommended to use category I requirements.

For buildings and spaces were the mechanical cooling capacity is not adequate to meet the required temperature categories the design documents must state, using one of the methods described in TR15251, how often the conditions are outside the required range.

6.1.1.1 Local thermal discomfort

Criteria for local thermal discomfort such as draught, radiant temperature asymmetry, vertical air temperature differences and floor surface temperatures shall also be taken into account when designing buildings and HVAC systems. Table B1.1.-3 presents the most important local thermal discomfort criteria at 3 category levels. For more background information see TR15251.

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6.1.2 Buildings without mechanical cooling

For the dimensioning of the heating system the same criteria as for mechanically ventilated, cooled and heated buildings shall be used (6.1.1).

In buildings without mechanical cooling the criteria for the thermal environment shall be specified using the method described in section 6.1.1 or using an alternative method that takes into account adaptation effects. This alternative method only applies for occupants with sedentary activities without strict clothing policies where thermal conditions are regulated primarily by the occupants through opening and closing of openings in the building envelope (windows).

Recommended criteria for the indoor operative temperature in buildings without mechanical cooling are presented in Annex B1.2

The upper limits presented in Annex B1.2 shall be used to design buildings and passive thermal controls (e.g. orientation of glazing and solar shading, thermal building capacity, size and adjustability of operable windows etc.) to avoid overheating.

For buildings and spaces were the building design and the natural ventilation system is not adequate to meet the required temperature categories the design documents must state, using one of the methods described in TR15251, how often the conditions are outside the required range

6.1.3 Increased air velocity

Under summer comfort conditions with indoor operative temperatures > 25 C increased air velocity can be used to compensate for increased air temperatures according to annex B1.3

6.2 Design for Indoor air quality (ventilation rates)

6.2.1 General

Indoor air quality shall be controlled by one or more of the following means: source control, ventilation, filtration, air cleaning.

National ventilation air flow rates shall be stated in Annex B2 if the default values in Annex B2 are not used.

Default ventilation airflow rates are presented in Annex B2. These values are design ventilation airflow rates intended for dimensioning of the ventilation system. During normal operation of the ventilation system, the ventilation flow rates can be different from the design ventilation flow rates.

For the default design ventilation rates presented in Annex B2, full mixing (ventilation efficiency of 1, EN13799) is assumed.

6.2.1.1 Source control

Source control shall be the primary strategy for controlling the level of air pollutants.

The main sources of pollutants shall be identified and eliminated or decreased by any feasible means.

6.2.1.2 Ventilation

The design requirements for the ventilation air flow rates shall take into account the pollutant emissions rates left after source control.

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6.2.1.3 Time periods used for determining air flow rates

The methods described in 6 assume that pollutants emissions are constant in each time period considered and lead to a constant design ventilation air flow rate for each time period. If occupation and pollutant loads vary in time, the designer shall specify the time periods considered for the calculation of the design ventilation air flow rates. These shall describe at least the assumed periods of occupancy and of non-occupancy.

6.2.1.4 Building damage

It must be evaluated if the required ventilation rate for indoor air quality is high enough to avoid building damage from condensation on surfaces, in the materials or in the structure. If not a higher ventilation rate must be used as design value

6.2.1.5 Design documentation

The design documents shall state:

which method and category is used for design;

which pollutant sources have been identified and processes used to eliminate or decrease those sources;

which method has been used to derive the required ventilation airflow rates?

The applied occupancy schedules must be provided in the documentation. Default occupant schedules are given in Annex B7.

6.2.2 Methods

6.2.2.1 General

Design parameters for indoor air quality shall be derived using one or more of the following methods:

Method based on perceived air quality

Method using criteria for pollutant concentration

Method based on pre-defined ventilation air flow rates

Within each method, the designer shall choose between different categories of indoor air quality and define which building category is to be used.

The method used shall be documented and it must be explained why the selected method is appropriate.

6.2.2.2 Method based on perceived air quality

The air shall be perceived to be fresh and pleasant rather than stale, stuffy and irritating. The dilution required for reducing the health risk from a specific air pollutant shall be evaluated separately from the ventilation rates required to obtain a desired perceived air quality (comfort). The highest of these

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values shall be used for design. If critical sources are identified for health, it shall be checked that they remain below the health threshold values (see sec 6.2.2.3). The total ventilation rate for the breathing zone is found by combining the ventilation for people and building calculated from the following formula

tot p R Bq n q A q Eq(1)

where qtot = total ventilation rate for the breathing zone, l/s n = design value for the number of the persons in the room, qp = ventilation rate for occupancy per person, l/(s* person) AR = room floor area, m2

qB = ventilation rate for emissions from building, l/(s,m2)

The perceived air quality levels are set for non-adapted persons. If in special cases the design will include adapted persons see TR15251.

The criteria are assumed to be independent of seasons.

6.2.2.3 Method using criteria for pollutant concentration

The ventilation rate required to dilute a pollutant shall be calculated by this equation: Gh 1

Qh = -------------- ----- Eq (2)

Ch,i - Ch,o v where: Qh is the ventilation rate required for dilution, in litre per second; Gh is the pollution load of a pollutant, in micrograms per second; Ch,i is the guideline value of a pollutant, see Annex B6 , in micrograms per m3; Ch,o is the supply concentration of pollutants at the air intake, in micrograms per m3;

v is the ventilation effectiveness

NOTE. Ch,i and Ch,o may also be expressed as ppm (vol/vol). In this case the pollution load Gh has to be expressed as l/s.

Equation (1) applies to steady-state conditions and the method requires that the supply air pollutant concentration is lower than the indoor.

To calculate the design ventilation air flow rate from Eq. (2), the most critical or relevant pollutant (or groups of pollutant) shall be identified and the pollution load in the space shall be estimated.

When this method is used it is required that CO2 representing the pollutant emission from people (bio effluents) shall be used as one of the gases.

Values depending on the category of indoor air are defined for CO2 in Annex B2. Threshold values for other sources are listed in Annex B6. Emission rates and outdoor concentrations for the gases considered shall be defined based on material testing or certification (see Annex B3) and local ambient air quality values.

Note: TR15251 shows examples of pollutants production and concentration, e.g. for CO2 or water vapour, together with sample calculations. Also calculations for non-steady state are shown.

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6.2.2.4 Method based on pre-defined ventilation air flow rates

This is a method to determine certain pre-defined minimum ventilation air flow rate estimated to meet requirement for both perceived air quality and health in the occupied zone.

The pre-defined ventilation air flow rates, ,shall be expressed by one or more of the following parameters: total design ventilation for people and building components (qtot); design ventilation per unit floor area (qm2); design ventilation per person (qp); design air change rates (ach); design opening areas (Atot). Default values are presented in Annex B2.

6.2.3 Non-residential buildings

6.2.3.1 Applicable methods

For the design of ventilation systems and calculation of design heating and cooling loads, the design ventilation rate shall be specified in the design documents based on national requirements, or when no national regulation is available, using one of the three methods described in this standard in 6.2.2.1.

The design ventilation air flow rates shall be used for designing any type of ventilation system, including mechanical-, natural- hybrid- and exhaust-ventilation systems.

6.2.3.2 Ventilation air flow rates during unoccupied periods.

In case the ventilation is shut off:

The designer shall determine the time and air flow rate needed to limit the concentration of pollutants emitted by materials prior to occupation.

Annex B2 gives default values for the minimum ventilation air to be delivered prior to occupation.

In case the air flow rate is lowered:

The ventilation air flow rate shall be at least equal to the air flow rate necessary to dilute emissions from building (Table B2.1.2-2)

The Annex B2 gives default values for the minimum ventilation air flow rate to be delivered to remove building emissions during un-occupied hours.

6.2.4 Residential buildings

6.2.4.1 Applicable methods

The design ventilation air flow rates shall be specified in the design documents, using one of the three methods described in this standard in 6.2.2.1.

The design ventilation air flow rates shall be used for designing mechanical, natural and hybrid ventilation systems.

Design ventilation air flow rates shall be specified as an air change per hour for each room, and/or outside air supply and/or required exhaust rates (bathroom, toilets, and kitchens) or given as an overall required air-change rate.

6.2.4.2 Ventilation air flow rates during un-occupied periods

If the ventilation rate is lowered during unoccupied hours, the ventilation system must start before the building is occupied again or shall not be ventilated during unoccupied hours below the values necessary to dilute emissions from building (Annex B2, Table B2.1.4-1)

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6.2.5 Access to operable windows

The building shall provide access to operable windows or operable elements in the facade to allow the building occupants to make airings and to provide contact to the outside. This applies to bedrooms and living rooms in dwellings and other buildings with rooms intended for sleep, e.g. elderly homes. It also applies in schools and child care facilities.

6.2.6 Filtration and air cleaning

The influence of position of outdoor air intakes, filtration and air cleaning shall be considered. (EN13779, TR15251)

If filtration and air cleaning is used the following points shall be considered:

Reducing the amount of airborne pollutants (pollens, molds, spores, particles, dust) from the outdoor

air intake by circulating the air through a filter.

Circulating secondary air through a filter or other air cleaning technology to reduce the amount of pollutants in the air

Reduce the concentration of odors and gaseous contaminants by circulating the secondary air or recirculating the return air (gas phase air cleaning)

Note: Design guidelines on air cleaning and filtration are given in EN13779 and ISO DIS 16814. How to partially substitute outside air by air cleaning is described in TR15251

6.3 Humidity

The humidity criteria depend partly on the requirements for thermal comfort and indoor air quality and partly on the physical requirements of the building (condensation, mould growth etc.). For special buildings (museums, historical buildings, churches) additional humidity requirements shall be taken into account. Humidification or dehumidification of room air is usually not required but if used excess humidification and dehumidification shall be avoided. The recommended design values of indoor humidity for occupied spaces with dehumidification and humidification systems given in Annex B2.2 shall be used.

6.4 Lighting

6.4.1 General

To enable people to perform visual tasks efficiently and accurately, appropriate lighting shall be provided.The degree of visibility and comfort is wide ranging governed by activity type and duration of required lighting criteria. The lighting shall be obtained by means of daylight, electric light or a combination of both.

Windows shall be the primary source of light during daylight hours and provide visual contact with the outside environment. Further the window design shall not cause visual discomfort or a loss of privacy.


To enable people to perform visual tasks efficiently and accurately, appropriate lighting shall be provided. The

degree of visibility and comfort is wide ranging governed by activity type and duration of required lighting criteria for work places as specified in EN12464-1 and for sports lighting in EN 12193. For some visual tasks in

buildings and spaces the required lighting criteria are presented in Annex B4, table B4-1.

Note: Emergency lighting is not within the scope of this document.

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The design illuminance levels shall be obtained by means of daylight, electric light or a combination of both. For reasons of comfort and energy in most cases the use of daylight is preferred. This depends on factors like standard occupancy hours, autonomy (portion of occupancy time during which there is enough daylight), location of the building (latitude), amount of daylight hours during summer and winter, etcetera.

To ensure good daylight provision, the daylight penetration in the spaces meant for human occupancy shall be fulfilled. PrEN 15193-1 provides details of occupancy periods and daylight availability and estimations.


The design illuminance levels shall be obtained by means of daylight, electric light or a combination of both. Criteria for daylight factor are included in Annex B4.

6.5 Noise

For design of ventilation the required sound levels shall be specified in the design documents using the recommended values listed in Annex B5.

Guidance for evaluation of noise at the design stage is found in EN 12354-part 5.

The noise from building service systems may disturb the occupants and prevent the intended use of the space or building. The noise in a space shall be evaluated using A-weighted equivalent sound pressure level, normalized with respect to reverberation time (Lea, nT, A) to take into account the sound absorption of the room. Leq, nT, A is defined in ISO EN16032 and ISO EN10052.

The tables in Annex B5 are only based on building service equipment noise and not outside noise.

Note. Often national requirements exist for noise from building service equipment inside or outside assuming

windows are closed.

These criteria apply to the sources from the building as well as the noise level from outdoor building service equipment The criteria shall be used to limit the sound pressure level from the mechanical equipment and to set sound insulation requirements for the noise from outdoors and adjacent rooms.

The values recommended in Annex B5 can be exceeded for a short term period if the occupants can control the operation of the equipment or the windows. Even in this case the rise of the sound pressure level over the values in the Annex B5 shall be limited to between 5 and 10 dB (A).

Ventilation shall not rely primarily on operable windows if the building is located in an area with a high outdoor noise level compared to the level the designer wishes to achieve in the indoor zone.

7 Indoor environment parameters for energy calculation

To perform a yearly energy calculation (EN ISO 13790) criteria for the indoor environment must be specified and documented.

Accepted exceedance of the criteria shall be specified (see TR15251)

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7.1 Thermal environment

As the energy calculations may be performed on seasonal, monthly of hourly basis (dynamic simulation) the indoor environment is specified accordingly. Indoor operative temperature criteria for heating and for cooling shall be specified.

7.1.1 Seasonal calculations

For seasonal and monthly calculations of energy consumption for heating and cooling respectively the same values of indoor operative temperature as for design (sizing) the heating and cooling systems shall be used (6.1) for each category of indoor environment. Assumptions regarding clothing level (EN ISO 9920) and activity level (EN ISO 8996) shall be listed.

7.1.2 Hourly calculations (dynamic simulation)

In dynamic simulation the energy consumption is calculated on an hourly basis. Recommended values for the acceptable range of the indoor operative temperature for heating and cooling are presented in Annex B1.4. The midpoint of the operative temperature range should be used as a target value but the indoor temperature may fluctuate within the range according to the energy saving features or control algorithm. If the cooling power is limited (mixed mode buildings) the excess indoor operative temperatures shall be estimated using one of the methods in TR15251.

Assumptions regarding clothing level (EN ISO 9920) and activity level (EN ISO 8996) shall be listed separately.

Assumptions related to allowable exceedance shall be described (TR15251).

7.2 Indoor air quality and ventilation

7.2.1 General

The minimum ventilation rate as specified in the design (section 6) shall be used for energy calculations during occupied hours

During un-occupied hours a lower ventilation rate can be specified (Annex B2.1.5) for energy calculations

In systems with variable air flow controlled by any criteria representing demand (e.g. timer, occupancy detection, change of pollution load etc.) the variation of ventilation rate over time (may vary between maximum and minimum depending on the occupancy and pollution load such as CO2 or moisture generation shall be taken into account in the energy calculations..

Ventilation air flow rates in naturally ventilated buildings shall be calculated based on building layout, location and weather conditions according to EN15242 or with dynamic thermal simulation tools.

In hybrid ventilation systems the air flow and resulting energy calculation is due to a combination of natural and mechanical means.


During the hours of operation the ventilation rates for energy calculations shall be the same as specified in Clause 6 for design load and energy calculations and dimensioning of the ventilation system.

To ensure good indoor air quality at the beginning of the occupancy, the ventilation shall start before the occupancy or a minimum ventilation rate shall be provided during unoccupied hours. If no national regulations exist the recommendations in Annex B2.1.2 may be used.

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In systems with variable air flow control and demand controlled ventilation the ventilation rate may vary between maximum, for full occupancy, and minimum, when the considered space is un-occupied. In case of CO2-controlled ventilation the CO2-concentration shall not exceed the design values. Recommended values for the excess of CO2 concentration above outdoors CO2 concentration are listed in Annex B2.1.3., Table B2.1.3-1.


In residential buildings the minimum ventilation rate shall be specified in the design (section 6, Annex B2.2) during occupied hours.

Residential buildings, both in case of mechanical and natural ventilation, shall be ventilated during unoccupied periods with a possibly lower ventilation rate than during the occupied period. This minimum ventilation rate shall be defined based on the pollution load of the spaces. If no national regulation is available the values in Annex B2.1.4 are recommended. National codes may allow complementary ventilation by airing to achieve this requirement in mild season.

7.3 Humidity

The criteria used for equipment design and sizing (6.1.3, annex B2.2) shall be used also in energy calculations (EN15243) Indoor air shall not be dehumidified to a lower relative humidity than the design values and not humidified into higher relative humidity than the design values Annex B2.2). Besides an upper limit for the absolute humidity shall be given. Unoccupied buildings shall not be humidified (with some exceptions such as museums) but may need to be dehumidified to prevent long term moisture damage.

7.4 Lighting


Energy calculations for lighting use in buildings shall be based on EN 15193-1. The required light level shall be obtained by daylighting (according to the daylight availability), electric lighting or a combination of both. The choice of light source has an impact on the building energy demand. Energy for illumination is calculated only for the occupied hours based on the agreed occupancy profile (see Annex B7). The quality of lighting shall be taken into account in the energy calculations according to EN 12464-1 and EN 12193. Some examples of EN 12464-1 are presented in Annex B4.


The lighting power required for a residential building shall be calculated according to prEN 15193-1 by the

summation of the power rating of each lamp installed in a room or area. Guidance on the installed lighting power requirements is given in CEN/TR 15193-2.

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Annex A1 (normative) Recommended criteria for the thermal environment

This annex includes all recommended criteria for the thermal environment.

A1.1 Recommended categories for mechanically heated and cooled buildings

Assuming different criteria for the PPD-PMV (EN ISO 7730) different categories of the indoor environment are established. Recommended PPD ranges are given in the table A1.1-1. For the design and dimensioning further criteria for the thermal environment (draught, vertical air temperature differences, floor temperature, and radiant temperature asymmetry) shall be taken into account (see table A1.1-3

Table A.1.1-1 Examples of recommended categories for design of mechanical heated and cooled buildings

Category

Thermal state of the body as a whole

PPD

%

Predicted

Mean Vote

I

II

III

III

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Table A1.1-2 presents design values for the indoor operative temperature in buildings that have active heating systems in operation during winter season and active cooling systems during summer season.

Assumed clothing thermal insulation level for winter and summer (clo-value) and activity level (met-value) are listed in table A1.1-2. Note that the operative temperature limits shall be adjusted when clothing levels and/or activity levels are different from the values mentioned in the table. A 50% relative humidity and low air velocities (< 0.15 m/s) is assumed

Table A.-2 Examples of recommended design values of the indoor operative temperature in winter en summer for buildings with mechanical cooling systems (for more examples see TR15251). A 50% relative humidity level and low air velocity level (< 0.1 m/s) is assumed

Type of building/ space Category Operative temperature oC

Minimum for heating (winter season), ~ 1,0 clo

Maximum for cooling (summer season), ~ 0,5 clo

Residential buildings, living spaces (bed rooms living rooms etc.)

Sedentary activity ~1,2 met

I

II

III

IV

Residential buildings, other spaces (kitchens, storages etc.)

Standing-walking activity ~1,5 met

I

II

III

Offices and spaces with similar activity (single offices, open plan offices, conference rooms, auditorium, cafeteria, restaurants, class rooms,


I

II

III

IV

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Local Thermal Discomfort

The following table gives criteria for local thermal discomfort parameters for the three categories for design of buildings and HVAC systems.

Table A1.1-3. Local thermal discomfort design criteria (for more information, see EN-ISO 7730 and TR15251) Draught Vertical air

temperature

difference

(head-ankle)

Range of floor

temperature

Radiant temperature asymmetry

PD

(Draught

Rate)

Maximum air

velocity a

PD Temp.

Difference b

PD Floor surface

temperature

range

PD Warm

ceiling

Cool

wall

Cool

ceiling

Warm

wall

[%]

Winter

[m/s]

summer

[m/s]

[%]

[C]

[%]

[C]

[%]

[C]

[C]

[C]

[C]

Category I

Category II

Category III

a Assuming an activity level of 1,2 met, a turbulence intensity of 40% and an air temperature of around 20 C in winter and 23 C in summer

b Difference between 1,1 and 0,1 m above the floor

c When the air temperature is above 25 C higher maximum air speeds are allowed and often even preferred (draught becomes pleasurable breeze); but only under the

condition that occupants have direct control over the air speed.

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A1.2 Acceptable indoor temperatures of buildings without mechanical cooling systems.

In figure A1.2-1 recommended indoor operative temperatures are presented for buildings without mechanical cooling systems. This alternative method only applies in occupant-controlled naturally conditioned spaces without strict clothing policies where thermal conditions are regulated primarily by the occupants through opening and closing of openings in the building envelope.

During the summer season and during the shoulder seasons (spring and autumn) so-called adaptive criteria (upper and lower temperature limits that change with the running mean outside temperature) shall by applied (see the cat. I, II and III upper and lower limits in Figure A1.2-1).

During the winter season, the same temperature limits shall be applied as presented in Annex A1.1. for buildings with mechanical cooling systems (winter upper and lower limits are not presented in figure A1.2-1).

Figure A1.2-1 Design values for the indoor operative temperature for buildings without mechanical cooling systems as a function of the exponentially-weighted running mean of the

external temperature.

rm = External Running mean temperature oC.

0 = Indoor Operative temperature oC.

rm = (1- ).{ ed -1 + . ed -2 + 2 ed -3..} (1) This equation can be simplified to rm = (1- )ed -1 + . rm-1 (2)

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Where

rm = running mean external air temperature for today

rm-1 = mean external air temperature for previous day

ed-1 is the daily mean external air temperature for the previous day

ed -2 is the daily mean external temperature for the day before and so on.

is a constant between 0 and 1. Recommended to use 0,8

The following approximate equation shall be used where records of daily mean external temperature are not available:

rm = (ed -1 + 0,8 ed -2 + 0,6 ed -3 + 0,5 ed -4 + 0,4 ed -5 + 0,3 ed -6 + 0,2 ed -7)/3,8 (3)

The operative temperatures presented in figure A1.2-1 must only be used for office buildings and other buildings of similar type used mainly for human occupancy with mainly sedentary activities, where there is easy access to operable windows and occupants may freely adapt their clothing to the indoor and/or outdoor thermal conditions.

The allowable indoor operative temperatures of figure A1.2-1 are plotted against the running mean external temperature rm. This is defined as the exponentially weighted running mean of the daily external temperature (see equations (2) and (3)).

The equations representing the lines in figure A1 are:

Category I upper limit: o = 0,33rm+ 18,8 + 2

lower limit: o = 0,33 rm + 18,8 - 3

Category II upper limit: o = 0,33 rm + 18,8 + 3

lower limit: o = 0,33 rm + 18,8 - 4

Category III upper limit: o = 0,33 rm + 18,8 + 4

lower limit: o = 0,33 rm + 18,8 5

The dotted line in the middle refers to the optimal operative temperature. The equation representing this line is: c = 0,33rm+ 18,8 where o = indoor operative temperature, oC

rm = running mean external temperature, oC

c = Optimal operative temperature, oC

The limits only apply when 10

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A1.3 Increased air velocity

Under summer comfort conditions with indoor operative temperatures > 25 C artificially increased air velocity can be used to compensate for increased air temperatures according to Table A1.3-1 only if the increased air velocity is under personal control. .

Table A1.3-1 Indoor operative temperature correction (o) that can be applied when buildings are equipped with fans, personal systems that provide building occupants with

personal control over air speed at workstation level. The correction value depends on the air speed range of the appliance.

Average Air Speed (Va) 0.6 m/s



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A1.4 Recommended indoor temperatures for energy calculations

Table A.4-1 Temperature ranges for hourly calculation of cooling and heating energy in three categories of indoor environment. ; During the between heating and cooling seasons (with rm between 10 and 15) temperature limits that lie in between the winter and summer values may be used. Air velocity is assumed < 0,1 m/s and RH~40% for heating season and

60% for cooling season

Type of building or space Category Temperature range for heating, oC

Clothing ~ 1,0 clo

Temperature range for cooling, oC

Clothing ~ 0,5 clo

Residential buildings, living spaces (bed rooms living rooms etc.)


I

II

III

IV

Residential buildings , other spaces (kitchens, storages etc.)

Standing-walking activity ~1,5 met

I

II

III

Offices and spaces with similar activity (single offices, open plan offices, conference rooms, auditorium, cafeteria, restaurants, class rooms,


I

II

III

IV

The mean design operative temperature can vary from the values shown to take account of e.g. local custom or a desire for energy saving so long as the within-day variation from the design temperature is within the given range, and the occupants are given time and opportunity to adapt to the modified design temperature.

During the between heating and cooling seasons (with rm between around 10 and 15 C) adjusted upper and lower temperature limits may be used that lie in between the winter and summer values mentioned in table A1.3-1.

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Annex A2 (normative)

Basis for the criteria for indoor air quality and

ventilation rates

A2.1 Design ventilation air flow rates

A2.1.1 General

Due to health reasons the minimum airflow rate is 4 l/s/person (Table A2.1.2-2) and the WHO Guideline values in Annex A6 is met. The default air flow rates given in Annex A2 are design ventilation air flow rates.

The default air flow rates given in this Annex assume complete mixing in the room (concentration of pollutants is equal in exhaust and in occupied zone). Ventilation rates shall be adjusted according to the ventilation effectiveness if the performance of air distribution differs from complete mixing according to EN13779.

A2.1.2 METHOD 1 - Method based on perceived air quality

The calculated design ventilation rate is from two components (a) ventilation to dilute/remove pollution from the occupants (bio effluents) and (b) ventilation to remove/dilute pollution from the building and systems. The ventilation for each category is the sum of these two components as illustrated with the equation (1) in 6.2.2.2.

The ventilation rates for occupants are presented for un-adapted.

The total ventilation rate will then depend on occupant density and building type. Examples of the total ventilation rates for non-industrial, non-residential buildings based on these values with default occupancy density are shown in TR15251.

A building is by default a low-polluting building unless prior activity has resulted in pollution of the building (e.g. smoking). In this case, the building shall be regarded as non-low polluting. The category very low-polluting requires that the majority of building materials used for finishing the interior surfaces meet the national or international criteria of very low-polluting materials. An example of how to define very low-polluting building materials is given in Annex A3.

Values for occupants (qp ) only are listed in Table A2.1.2-1

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Table A2.1.2-1 Design ventilation rates for non-adapted persons for diluting emissions (bioeffluents) from people for different categories

Category Expected Percentage Dissatisfied

Airflow per non-adapted person

l/(s.pers)

I

II

III

IV

The total ventilation rate must never be lower than 4 l/s per person

The ventilation rates (qB) for the building emissions are calculated according to Table A2.1.2-2:

Table A2.1.2-2 Design ventilation rates for diluting emissions from buildings

Category Very low polluting building

l/(s m2)

Low polluting building

l/(s m2)

Non low-polluting building

l/(s m2)

I

II

III

IV

Minimum total ventilation rate for health

Table A2.1.2-3. Example of design ventilation air flow rates for a single-person office of 10 m2 in a low polluting building (un-adapted person)

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Category Low-polluting building

l/(s*m2)

Airflow per non-adapted person

l/(s*person)

Total design ventilation air flow rate for the room

l/s l/(s*person) l/(s* m2)

I

II

III

IV

A2.1.3 METHOD 2 - Method using limit values of gas concentration

The design ventilation rates are calculated based on a mass balance equation for the pollutants concentration in the space taking into account the outdoor pollutant concentration.

If CO2 is used as a tracer of human occupancy, the default limit values are extracted from Table A2.1.3.5. Further recommended criteria for the CO2 calculation are included in TR15251. The listed CO2 values can also be used for Demand Controlled Ventilation.

Table A2.1.3-1. Default design CO2 concentrations above outdoor concentration assuming a standard CO2 emission of 20 L/(h/person).

Category Corresponding CO2 concentration above outdoors in PPM for non-adapted

persons

I

II

III

IV

Default outside concentration average is 400 ppm (350-500 ppm)

A2.1.4 Ventilation air flow rates for residential buildings

Pre-defined ventilation air flow rates can be given on national level based on one or more of the following components: Total air change rate for the dwelling; Exhaust air flows for specific rooms; Supply air flows for specific rooms.

Annex A2.1.4 gives default values for the three components. The values assume that air is supplied in living rooms and extracted from wet rooms.

Calculate both the total air change rate for the entire dwelling (Table A2.1.4-1) and the exhaust air flow rate from wet rooms (Table A2.1.4-1). The higher of the two is used.

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Table A2.1.4-1 Three methods for ventilation based on pre-defined ventilation air flow rates: Total ventilation (1), Supply air flow (2) and (3) and supplemented by exhaust air flow.

Cate

gory

Total ventilation including air infiltration

( 1)

Supply air flow per. person

(2)

Supply air flow based on perceived IAQ for adapted persons

(3)

Supply air flow Bed room level (l/s)

(4)

Exhaust air flow, l/s

peak or boost flow for high demand

l/s,m2 ach l/s*per

qp

l/s*per

qB

l/s,m2

Master bed-room

l/s

Other bed-room

l/s

Kit-chen

(3a)

Bath-rooms

(3b)

Toilets

(3c)

I

II

III

IV*

* Category IV is intended for the evaluation of IAQ in existing buildings where the space for installations are limited.

Supply air flow for method 3 is based on eq (1) from section 6.2.2.2

tot p R Bq n q A q Eq (1)

where qtot = total ventilation rate for the breathing zone, l/s n = design value for the number of the persons in the room, qp = ventilation rate for occupancy per person, l/(s* person) AR = room floor area, m2

qB = ventilation rate for emissions from building, l/(s,m2)

Note Table A2.1.4-1: The values assume that outdoor air is the primary source, not air transferred from other rooms. These values may be converted to l/s/m2 of floor area at national level depending on the average density of occupation of dwellings.

Note Table A1.4-1: Column 3 and 4: The ventilation air flow rates must be available when the rooms are occupied. The design can take into account that not all bedrooms are occupied at the same time, e.g. during daytime.

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Table A2.1.4-2 Design CO2 concentrations in occupied rooms and in bedrooms (concentrations above outdoor concentration assuming a standard CO2 emission of 20 l/h.person in occupied rooms and of 13,6 L/h per person in bedrooms assuming an average bedroom metabolism of 0,8 met)

Category Design CO2 concentration for occupied rooms

(ppm above outdoors)

Design CO2 concentration for

bedrooms

(ppm above outdoors)

I

II

III

IV

Note table A2.1.4-2: 4; 7 and 10 l/s/person corresponds to an air change rate of 1,2; 2,0 and 2,9 ACH, The above values in Table A2.1.4-4 correspond to the equilibrium concentration when the air flow rate is 4, 7, 10 l/s for cat. I, II, III respectively and the CO2 emission is 20l /h and 13.6 l/h for living rooms and bedrooms respectively respectively for a 10 m room (room height 2,5 m).

Table A2.1.4-3 gives a methodology for defining default design opening areas for natural ventilation systems in dwelling. The opening areas must be provided as supply/extract grilles, stack ducts, window grilles, or similar system.

Table A2.1.4-3 - Default design opening areas for dwellings (values to be defined on national levels).Values for bedrooms and living rooms may be given per m floor area or as fixed values per room.

Extract Kitchen, bathrooms and toilets (cm2)

Supply Bedrooms and living rooms (cm2)

Default design opening area

A2.1.5 Ventilation air flow rate during unoccupied periods

A2.1.5.1 Non-residential buildings

In case the ventilation is shut off, the minimum amount of air to be delivered prior to occupation is by default: 1 volume within two hours of the zone to be ventilated.

In case the ventilation is lowered, the total air flow rate for diluting emissions from building is between 0,15 and 0,6 l/s.m2 of floor area (table A2.1.2-2) .

A2.1.5.2 Residential buildings

The total air flow rate needed to deal with building materials emissions is between 0,1 and 0,25 l/(s*m2 ) of floor area (Table A2.1.4-1).

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A2.2 The Recommended criteria for dimensioning of humidification and de-humidification

For buildings with no other humidity requirements than human occupancy (e.g. offices, schools and residential buildings), humidification or dehumidification is usually not needed.

Usually humidification or dehumidification is needed only in special buildings like museums, certain health care spaces, process control, paper industry etc.). If humidification or dehumidification is used the values in the table A2.2-1 is recommended as design values under design conditions.

Table A2.2-1 Example of recommended design criteria for the humidity in occupied spaces if humidification or dehumidification systems are installed

Type of building/space Category Design relative humidity for dehumidification, %

Design relative humidity for humidification, %

Spaces where humidity criteria are set by human occupancy. Special spaces (museums, churches etc.) may require other limits

I

II

III

Besides it is recommended to limit the absolute humidity to 12g/kg

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Example on how to define low

and very low polluting buildings

The building is low or very low polluted if the majority of the interior materials are low or very low emitting. Low and very low emitting materials are stone, glass, ceramics and non-treated metal, which are known to show no emissions into indoor air, and materials that show low or very low emissions when tested in a ventilated test chamber after 28 days in line with CEN/TS16516 or ISO 16000-3/-6/-9/-11, with the results calculated for the European Reference Room as specified in CEN/TS 16516.

Table A3-1: Criteria for the different building types.

SOURCE Low emitting products for low polluted buildings

Very low emitting products for very low polluted buildings

Total VOCs TVOC (as in CEN/TS 16516)

Formaldehyde

Any C1A or C1B classified carcinogenic VOC

R value (as in CEN/TS 16516)

Compliance can be shown by presentation of a test report, issued by a testing laboratory with an ISO 17025 accreditation, or by showing a valid attestation of compliance with any regulation or voluntary label that includes the above (or more stringent) limit values after 28 days storage in a ventilated test chamber (or earlier).

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Examples of criteria for

lighting

Table A4-1 Examples of criteria for some buildings and spaces according to EN 12464.

Ref. no. acc. to EN 12464-1:2011

Type of area, task or activity m

lx

UGRL

Uo

Ra

Specific requirements

5.26.2

5.26.5

Offices - Writing, typing, reading,

data processing, -

Conference and meeting rooms

DSE-work, see 4.9

Lighting should be controllable.

5.36.1-5.36.3 Educational buildings -

Classrooms, tutorial rooms,

Classroom for evening classes

and adults education, Auditorium,

lecture halls

Lighting should be controllable.

5.36.24 Educational premises Educational buildings - Sports

halls, gymnasiums, swimming

pools

See EN 12193 for training

conditions.

Table A4-2 Daylight availability classification as a function of the daylight factor DCa,j of the raw building carcass opening and DSNA 15193

Vertical Facades

Daylight factor DCa,j

Roof lights

Daylight factor DSNA

Classification of daylight availability

DCa,j 6 %

6 % > DCa,j 4 %

4 % > DCa,j 2 %

DCa,j < 2 %

a Values of DSNA > 10 % should be avoided due to danger of overheating

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Indoor system noise criteria

of some spaces and buildings

Table A5-1 Examples of design Equivalent Continuous Sound Level, Leq, nT,A [dB(A)] for continuous sources

Building Type of space Equivalent Continuous Sound Level

Leq, nT,A [dB(A)]

I II III

Residential Living-room

Bedrooms

Places of assembly

Auditoriums

Libraries

Cinemas

Museums

Commercial Retail Stores

Department stores, Supermarkets

Hospitals

Bedrooms

Wards

Operating theatres

Hotels Hotel rooms

Reception, Lobbies

Offices

Small offices

Landscaped offices

Conference rooms

Restaurants

Cafeterias

Bars, Dining rooms

Kitchens

Schools Classrooms

Gymnasiums

Sport Covered sport facilities

General Service rooms, Corridors

Toilets

The values given in Table A5-1 refer to noise generated by building service systems inside the considered room.

The calculated values must be normalized with reference to the reverberation time of the considered space. Typical reference value for residences, small offices and similar is 0.5 s and for large spaces this is 0,8.

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Annex A6 (informative) WHO health-based criteria for

indoor air

Table A6-1, 2nd column gives suggested guideline values for indoor and outdoor air pollutants as formulated by the World Health Organization (WHO). For some pollutants no indoor air requirements have been defined yet by WHO. For those values only WHO outdoor requirements are presented, see the 3rd column.

Table A6-1 WHO guidelines values for indoor and outdoor air pollutants.

Pollutant WHO

Indoor Air Quality guidelines 2010

WHO Air Quality guidelines 2005

Benzene No safe level can be

determined -

Carbon monoxide

15 min. mean: 100 mg/m3 1h mean: 35 mg/m3 8h mean: 10 mg/m3 24h mean: 7 mg/m3

-

Formaldehyde 30 min. mean: 100 g/m3 -

Naphthalene Annual mean: 10 g/m3 -

Nitrogen dioxide 1h mean: 200 g/m3

Annual mean: 40 mg/m3 -

Polyaromatic Hydrocarbons (e.g. Benzo Pyrene A B[a]P)

No safe level can be determined

-

Radon 100 Bq/m3

(sometimes 300 mg/m3, country-specific)

-

Trichlorethylene No safe level can be

determined -

Tetrachloroethylene Annual mean: 250 g/m3

Sulfure dioxide - 10 min. mean: 500 g/m3 24h

mean: 20 mg/m3

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Ozone - 8h mean:100 g/m3

Particulate Matter PM 2,5

- 24h mean: 25 g/m3

Annual mean: 10 g/m3

Particulate Matter PM 10

- 24h mean: 50 g/m3

Annual mean: 20 g/m3

WHO Air Quality Guidelines values may be considered as reference for Indoor air Quality when no other guideline or national recommendation for indoor air quality value exists. Due to health effects confirmed at lower concentrations than current limit values and carcinogenic effect, the level of PAHs, particles, benzene should always be kept as low as possible.

Table A6.1, 2nd column gives suggested guideline values for indoor air pollutants as formulated by the World Health Organization (WHO). For some pollutants no indoor air requirements have been defined yet by WHO. For those values only WHO outdoor requirements are presented, see the 3rd column.

In case of specific indoor pollution, ventilation rates shall be adapted to optimize the diluting effect of ventilation and additional air cleaning strategies can be considered.

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Annex A7 (informative) Occupant schedules for energy calculations

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Annex B1 (informative) Recommended criteria for the thermal environment

This annex includes all recommended criteria for the thermal environment.

B1.1 Recommended categories for mechanically heated and cooled buildings

Assuming different criteria for the PPD-PMV (EN ISO 7730) different categories of the indoor environment are established. Recommended PPD ranges are given in the table B1.1-1. For the design and dimensioning further criteria for the thermal environment (draught, vertical air temperature differences, floor temperature, and radiant temperature asymmetry) shall be taken into account (see table B1.1-3

Table F.1.1-1 Examples of recommended categories for design of mechanical heated and cooled buildings

Category

Thermal state of the body as a whole

PPD

%

Predicted

Mean Vote

I < 6 -0.2 < PMV < + 0.2

II < 10 -0.5 < PMV < + 0.5

III < 15 -0.7 < PMV < + 0.7

III < 25 -1.0 < PMV < + 1.0

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Table B1.1-2 presents design values for the indoor operative temperature in buildings that have active heating systems in operation during winter season and active cooling systems during summer season.

Assumed clothing thermal insulation level for winter and summer (clo-value) and activity level (met-value) are listed in table B1.1-2. Note that the operative temperature limits shall be adjusted when clothing levels and/or activity levels are different from the values mentioned in the table. A 50% relative humidity and low air velocities (< 0.15 m/s) is assumed

Table F.-2 Examples of recommended design values of the indoor operative temperature in winter en summer for buildings with mechanical cooling systems (for more examples see TR15251). A 50% relative humidity level and low air velocity level (< 0.1 m/s) is assumed

Type of building/ space Category Operative temperature oC

Minimum for heating (winter season), ~ 1,0 clo

Maximum for c

Documents

EN-15251-standard.pdf