SIST EN 14501:2006
(Main)Blinds and shutters - Thermal and visual comfort - Performance characteristics and classification
Blinds and shutters - Thermal and visual comfort - Performance characteristics and classification
This European Standard applies to the whole range of shutters, awnings and blinds defined in EN 12216, described as solar protection devices in this European Standard.
It states the properties that shall be taken into account when comparing products.
It also specifies the corresponding parameters and classifications to quantify the following properties:
- for the thermal comfort:
- the solar factor (total solar energy transmittance);
- the shading factor;
- the secondary heat transfer factor;
- the direct solar transmittance;
- for the visual comfort:
- the opacity control;
- the night privacy;
- the visual contact with the outside;
- the glare control;
- the daylight utilisation;
- the rendering of colours.
NOTE For other purposes, more detailed methods using different parameters can be used.
Some of the characteristics (e.g. gtot) are not applicable when products are not parallel to the glazing (e.g. folding-arm awnings).
This European Standard is not applicable to the products using fluorescent materials.
Abschlüsse - Thermischer und visueller Komfort - Leistungsanforderungen und Klassifizierung
Diese Europäische Norm gilt für sämtliche Arten von Abschlüssen, Markisen und Jalousien, die in EN 12216 definiert sind und in dieser Europäischen Norm als Sonnenschutzeinrichtungen bezeichnet werden.
In ihr sind die Eigenschaften festgelegt, die bei einem Vergleich von Produkten zu berücksichtigen sind.
Darüber hinaus sind die entsprechenden Parameter und Klassifizierungen zur quantitativen Bestimmung der folgenden Eigenschaften festgelegt:
- Für den thermischen Komfort:
- des Sonnenfaktors (Gesamtenergiedurchlassgrad);
- des sekundären Wärmeabgabegrades nach innen;
- des direkten Transmissionsgrades.
- Für den visuellen Komfort:
- der Regulierung der Lichtdurchlässigkeit;
- des Sichtschutzes bei Nacht;
- des Sichtkontaktes nach außen;
- des Blendschutzes;
- der Tageslichtnutzung;
- des Farbwiedergabeindexes.
ANMERKUNG Für andere Verwendungszwecke können detailliertere Verfahren mit anderen Parametern angewendet werden.
Einige Merkmale (z. B. gtot) sind nicht anwendbar, wenn Produkte nicht parallel zur Verglasung angebracht sind (z. B. Gelenkarmmarkisen).
Diese Europäische Norm ist nicht auf Produkte anwendbar, bei denen fluoreszierende Materialien verwendet werden.
Fermetures et stores - Confort thermique et lumineux - Caractérisation des performances et classification
Rolete in polokna – Toplotno in vizualno ugodje – Delovne karakteristike in klasifikacija
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 14501:2006
01-februar-2006
Rolete in polokna – Toplotno in vizualno ugodje – Delovne karakteristike in
klasifikacija
Blinds and shutters - Thermal and visual comfort - Performance characteristics and
classification
Abschlüsse - Thermischer und visueller Komfort - Leistungsanforderungen und
Klassifizierung
Fermetures et stores - Confort thermique et lumineux - Caractérisation des performances
et classification
Ta slovenski standard je istoveten z: EN 14501:2005
ICS:
91.060.50 Vrata in okna Doors and windows
SIST EN 14501:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 14501:2006
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SIST EN 14501:2006
EUROPEAN STANDARD
EN 14501
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2005
ICS 91.060.50
English version
Blinds and shutters - Thermal and visual comfort - Performance
characteristics and classification
Fermetures et stores - Confort thermique et lumineux - Abschlüsse - Thermischer und visueller Komfort -
Caractérisation des performances et classification Leistungsanforderungen und Klassifizierung
This European Standard was approved by CEN on 27 June 2005.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 14501:2005: E
worldwide for CEN national Members.
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SIST EN 14501:2006
EN 14501:2005 (E)
Contents
page
Foreword.3
Introduction .4
1 Scope .4
2 Normative references .5
3 Terms, definitions and symbols.5
4 Notations used.7
4.1 General.7
4.2 Visual or solar properties .7
4.3 Geometry of the radiation .7
4.4 Optical factors.8
5 Thermal comfort.8
5.1 General.8
5.2 Control of solar gains – Total solar energy transmittance g .9
tot
5.3 Secondary heat gains – Secondary heat transfer factor q .11
i, tot
5.4 Protection from direct transmission – Normal/normal solar transmittance ττττ .11
e, n-n
6 Visual comfort.12
6.1 General.12
6.2 Opacity control.14
6.3 Glare control.14
6.4 Night privacy .16
6.5 Visual contact with the outside.16
6.6 Daylight utilisation.17
6.7 Rendering of colours.18
Annex A (normative) Reference glazings.19
A.1 General.19
A.2 Glazing A .19
A.3 Glazing B .19
A.4 Glazing C .20
A.5 Glazing D .21
Annex B (informative) The meaning of the secondary internal heat transfer factor q .22
i, tot
Annex C (informative) Example of performance presentation .23
C.1 Thermal comfort.23
C.2 Visual comfort.24
Bibliography .25
2
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SIST EN 14501:2006
EN 14501:2005 (E)
Foreword
This European Standard (EN 14501:2005) has been prepared by Technical Committee CEN/TC 33 “Doors,
windows, shutters, building hardware and curtain walling”, the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an identical text or
by endorsement, at the latest by February 2006, and conflicting national standards shall be withdrawn at the latest
by February 2006.
No existing European Standard is superseded.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark,
Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
3
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SIST EN 14501:2006
EN 14501:2005 (E)
Introduction
This European Standard is a part of a series of standards dealing with blinds and shutters for buildings as defined
in EN 12216.
The methods of characterisation are related to performance requirements required as a complement to intrinsic
performances (specific requirements) that internal blinds, external blinds or shutters shall fulfil as specified in
EN 13120, EN 13561 and EN 13659.
The present European Standard is mainly based on the European work performed in TC 89 relating to solar and
light transmittance of solar protection devices combined with glazing and the Technical Report CIE 130.
1 Scope
This European Standard applies to the whole range of shutters, awnings and blinds defined in EN 12216,
described as solar protection devices in this European Standard.
It states the properties that shall be taken into account when comparing products.
It also specifies the corresponding parameters and classifications to quantify the following properties:
for the thermal comfort:
the solar factor (total solar energy transmittance);
the secondary heat transfer factor;
the direct solar transmittance;
for the visual comfort:
the opacity control;
the night privacy;
the visual contact with the outside;
the glare control;
the daylight utilisation;
the rendering of colours.
NOTE For other purposes, more detailed methods using different parameters can be used.
Some of the characteristics (e.g. g ) are not applicable when products are not parallel to the glazing (e.g. folding-
tot
arm awnings).
This European Standard is not applicable to the products using fluorescent materials.
4
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EN 14501:2005 (E)
2 Normative references
The following referenced documents are indispensable for the application of this European Standard. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced document
(including any amendments) applies.
EN 410, Glass in building — Determination of luminous and solar characteristics of glazing
EN 12216:2002, Shutters, external blinds, internal blinds — Terminology, glossary and definitions
EN 13363-1, Solar protection devices combined with glazing — Calculation of solar and light transmittance — Part
1: Simplified method
EN 13363-2:2005, Solar protection devices combined with glazing — Calculation of total solar energy
transmittance and light transmittance — Part 2: Detailed calculation method
1
prEN 14500 , Blinds and shutters — Thermal and visual comfort — Test methods
3 Terms, definitions and symbols
For the purposes of this European Standard, the terms and definitions given in EN 12216:2002 and the following
apply.
3.1
transmittance ττττ
ratio of the transmitted flux to the incident flux (see Figure 1)
NOTE A more detailed definition is given in prEN 14500.
3.2
reflectance ρρ
ρρ
ratio of the reflected flux to the incident flux (see Figure 1)
NOTE A more detailed definition is given in prEN 14500.
3.3
absorptance αααα
ratio of the absorbed flux to the incident flux (see Figure 1)
1
To be published.
5
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SIST EN 14501:2006
EN 14501:2005 (E)
Key
1 Solar protection device
2 Incident radiation E
3 Transmitted radiation τ × E
4 Absorbed radiation α × E
5 Reflected radiation ρ × E
Figure 1 — Representation of the optical factors
3.4
openness coefficient
ratio between the area of the openings and the total area of the fabric
NOTE 1 For identical fabrics that differ only by the colour, the openness coefficient is considered as independent of the colour.
The value of the openness coefficient should be measured for the darkest colour.
NOTE 2 The openness coefficient is determined according to prEN 14500.
3.5
solar factor g (total solar energy transmittance)
ratio between the total solar energy transmitted into a room through a window and the incident solar energy on the
window
g is the solar factor of the glazing alone
g is the solar factor of the combination of glazing and solar protection device
tot
3.6
shading factor F
c
ratio of the solar factor of the combined glazing and solar protection device g to that of the glazing alone g
tot
g
tot
F =
c
g
NOTE In some countries, F is known as z
c
3.7
secondary internal heat transfer factor q
i, tot
the part of the total absorbed radiation which is flowing inwards through the glazing and the shading device
combined
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3.8
colour rendering index R
a
index designed to express synthetically a quantitative evaluation of the differences in colour between eight test
colours lit directly by the standard illuminant D and by the same illuminant transmitted through the solar protection
65
device
3.9
operative temperature θ
op
uniform temperature of a room in which an occupant would exchange the same amount of heat by radiation plus
convection as in the actual non-uniform environment
NOTE For more information on the calculation of θ it is recommended to refer to EN ISO 13791 or EN ISO 13792.
op,
4 Notations used
4.1 General
For the purpose of this European Standard, the optical factors τ (transmittance), ρ (reflectance) and α
(absorptance) are labelled with subscripts which indicate:
visual or solar properties;
the geometry of the incident and the transmitted or reflected radiation.
4.2 Visual or solar properties
According to the respective spectrum the following subscripts are used:
« » solar (energetic) characteristics, given for the total solar spectrum, (wavelengths λ from 300 nm
e
to 2500 nm), according to EN 410;
« » visual characteristics, given for the standard illuminant D weighted with the sensitivity of the
v 65
human eye (wavelengths λ from 380 nm to 780 nm), according to EN 410.
4.3 Geometry of the radiation
The following subscripts are used to indicate the geometry of the incident radiation and the geometry of the
transmitted or reflected radiation (see Figure 2). For a more detailed definition see prEN 14500.
« » for directional (fixed, but arbitrary direction θ);
dir
« » for normal, or near normal in case of reflected radiation, the angle of incidence is θ = 0°,
n
or θ ≤ 8° respectively;
« » for hemispherical (collected in the half space behind the sample plane);
h
« » for diffuse.
dif
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EN 14501:2005 (E)
Key
1 Solar protection device
2 Incident directional light or solar radiation
3 Transmitted direct component of light or solar radiation
4 Transmitted diffuse component of light or solar radiation
Figure 2 — Direct and diffuse components of transmitted radiation
4.4 Optical factors
The optical factors are designated as follows:
τ normal/normal solar transmittance;
e, n-n
τ normal/normal light transmittance;
v, n-n
τ normal/diffuse light transmittance;
v, n-dif
τ normal/hemispherical light transmittance;
v, n-h
τ diffuse/hemispherical light transmittance.
v, dif-h
5 Thermal comfort
5.1 General
Thermal comfort is mainly governed by the operative temperature θ within the room. θ depends on the air
op op
temperature, the air velocity and the temperature of the surrounding surfaces.
Solar gains shall be controlled in order to limit the operative temperature. The classification of the total solar energy
transmittance g is given in 5.2.4.
tot
Solar protection devices influence the thermal comfort in three aspects:
The mean operative temperature and/or the cooling loads are influenced by the solar gains which depend
on the size of the windows and the total solar energy transmittance g .
tot
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The solar protection device may cause higher local values of θ when irradiated by the sun due to higher
op
temperatures on the inner surface of the glazing or solar protection device. This effect is quantified by the
secondary internal heat transfer factor q .
i, tot
The solar protection device may prevent persons and surroundings in the room from being irradiated
directly. This effect is quantified by the direct-direct solar transmittance τ .
e, dir-dir
The performance classes for the thermal comfort used in the following clauses are specified in Table 1.
Table 1 — Definition of classes
Influence on thermal comfort
0 1 2 3 4
Class
very good
very little effect little effect moderate effect good effect
effect
5.2 Control of solar gains – Total solar energy transmittance g
tot
5.2.1 General
The limitation of solar gains is one of the most important aspects of summer thermal comfort when there is no
mechanical cooling system. The solar gains are directly proportional to the total solar energy transmittance g .
tot
g depends on the glazing and the solar protection device g may be determined for the four different reference
tot tot
glazings given in Annex A using either the methodology given in 5.2.2 or in 5.2.3. For general product labelling
(independent from the installation conditions), the calculation according to 5.2.2 and the reference glazing C,
specified in Annex A, shall be used.
The solar factor g of glazing alone, needed for the calculation of g shall be calculated according to EN 410.
tot,
NOTE 1 The influence of solar protection devices on the solar gains can also be represented by the shading factor F . The
C
shading factor depends not only on the solar protection device but also on the glazing. If F is used for product characterisation,
C
it should be given for the 4 different reference glazings, defined in Annex A.
For windows with slatted or louvered devices, the values of the total solar factor g shall be specified for at least
tot
two positions:
the fully closed position of the slats at normal incidence;
the slats tilted at 45° and irradiation with 30° altitude angle, 0° azimuth angle.
In the case of roller shutters with light and ventilation slots, g shall be calculated:
tot
in the fully extended and closed position at normal incidence;
in the fully extended and open position at normal incidence.
corr
NOTE 2 For slatted or louvered devices tilted at 45° the values τ specified in EN 13363-1 can be used as the direct-
e
hemispherical solar transmittance except for mirror-finish products and under the boundary condition that there is no direct solar
transmission for the tilt angle of the slats under consideration.
NOTE 3 In the near future there will be a standard for the direct calorimetric measurement of g .
tot
NOTE 4 For a more detailed method for the calculation of the transmittance and the reflectance of slatted devices, see the
calculation method given in EN 13363-2. The view factors given in Annex A of EN 13363-2:2005 are only applicable for venetian
blinds with a ratio of d/l =1 for slat width l and slat distance d. For the cases described above see prEN 14500.
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5.2.2 Determination of g – Simplified method: installation conditions unknown
tot
When the installation conditions are unknown, g shall be calculated according to EN 13363-1.
tot
The necessary data for the calculation are the following:
τ solar transmittance of the product;
e
ρ solar reflectance of the outer surface of the product;
e
g solar factor of the glazing;
U thermal transmittance of the glazing.
5.2.3 Determination of g – Detailed method: installation conditions known
tot
When the site installation conditions are known and/or more accurate values are required, g shall be calculated
tot
according to EN 13363-2.
The necessary data for the calculation are the following:
τ(λ) normal/hemispherical spectral transmittance of the product;
n-h
ρ(λ) and ρ’(λ) normal/hemispherical spectral reflectances of the product for each side;
n-h n-h
ε, ε' emissivities of the product sides;
C openness coefficient as a measure for the size of the openings (fabrics only);
o
the spectral characteristics of each pane of the glazing;
the emissivity of each surface of each pane of the glazing;
the thickness and nature of gas space.
NOTE 1 In EN 13363-2 two different sets of boundary conditions are specified: Summer conditions and reference (mean
winter) conditions. Care should be taken to choose the correct set of boundary conditions according to the project specifications
and the national regulations.
NOTE 2 If spectral data for ρ(λ), ρ´(λ) and τ(λ) are not available, solar data can be used. This will reduce the accuracy of the
calculations.
5.2.4 Performance classes
The classification of g is specified in Table 2 with the classes quoted in Table 1.
tot
Table 2 — Total solar energy transmittance g — Classification
tot
Class 0 1 2 3 4
g g ≥ 0,50 0,35 ≤ g < 0,50 0,15≤ g < 0,35 0,10 ≤g < 0,15 g < 0,1
tot tot tot tot tot tot
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5.3 Secondary heat gains – Secondary heat transfer factor q
i, tot
5.3.1 General
The total solar energy transmitted through a facade consists of two parts:
radiation in the solar range, measured by the solar transmittance τ ;
e, tot
heat (thermal radiation and convection), measured by the secondary heat transfer factor q .
i,tot
The secondary heat transfer factor q of the combination of glazing and solar protection device shall be calculated
i, tot
with the following equation:
q = g – τ
i, tot tot e, tot
q may be determined for the four different reference glazings given in Annex A using either the methodology
i,tot
given in 5.3.2 or in 5.3.3. For general product labelling (independent from the installation conditions) the calculation
for q according to 5.3.2 and the reference glazing C, specified in Annex A, shall be used.
i,tot
NOTE An example explaining the meaning of q is given in Annex B.
i, tot
5.3.2 Determination of q – Simplified method
i, tot
The direct solar transmittance τ and the total solar transmittance g of the combination of a glazing and a solar
e, tot tot
protection device shall be calculated according to EN 13363-1.
5.3.3 Determination of q – Detailed method
i, tot
The direct solar transmittance τ and the total solar transmittance g of the combination of a glazing and a solar
e, tot tot
protection device shall be calculated according to EN 13363-2.
NOTE In EN 13363-2 two different sets of boundary conditions are specified: Summer conditions and reference (mean
winter) conditions. Care should be taken to choose the correct set of boundary conditions according to the project specifications
and the national regulations.
5.3.4 Performance classes
The classification of q is specified in Table 3 with the classes quoted in Table 1.
i, tot
Table 3 — Secondary Heat transfer factor q — Classification
i, tot
Class 0 1 2 3 4
q q ≥ 0,30 0,20 ≤ q < 0,30 0,10 ≤ q < 0,20 0,03 ≤ q < 0,10 q < 0,03
i, tot i, tot i, tot i, tot i, tot i, tot
5.4 Protection from direct transmission – Normal/normal solar transmittance ττ
ττ
e, n-n
5.4.1 General
The ability of a solar protection device to protect persons and surroundings from direct irradiation is measured by
the direct/direct solar transmittance τ of the device in combination with a glazing. For the sake of simplicity,
e, dir-dir
the normal-normal solar transmittance τ is used as a measure for this property.
e, n-n
5.4.2 Determination
The normal/normal solar transmittance τ shall be determined according to prEN 14500.
e, n-n
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5.4.3 Performance classes
The classification of τ is specified in Table 4 with the classes quoted in Table 1.
e, n-n
Table 4 — Normal/normal solar transmittance ττ — Classification
ττ
e, n-n
Class 0 1 2 3 4
ττττ τ ≥ 0,20 0,15 ≤ τ < 0,20 0,10 ≤ τ < 0,15 0,05 ≤ τ < 0,10 τ < 0,05
e, n-n e, n-n e, n-n e, n-n e, n-n e, n-n
NOTE Slatted or louvered devices with non-perforated slats are class 4 when the slats are tilted in a way that there is no
direct penetration of the sun.
6 Visual comfort
6.1 General
Depending on the geometry of the incident and the transmitted radiation, the components of the light transmission
concern different aspects of visual comfort.
When the opening is directly lit by the sun:
the incident radiation is mainly directional;
the transmitted radiation is partially directional (τ ), partially diffuse (τ );
v, dir-dir v, dir-dif
the total transmitted light flow is the sum of these two components.
τ τ τ
v, dir-h = v, dir-dir + v, dir-dif
These characteristics depend on the incidence angle θ.
The value τ is representative of the global reduction of natural light by the solar protection device when the
v, dir-h
light is coming from one specific direction. If an average value is required, τ is representative.
v, dif-h
The direct part of transmitted radiation τ represents the light passing through the holes in the solar protection
v, dir-dir
device under incidence θ. It allows recognition of shapes, and has a favourable influence on vision to the outside,
but is unfavourable for night privacy.
It may also be the basis of two factors of visual discomfort:
direct vision of the solar disc;
solar spots on the floor or the office furniture.
The diffused part τ of transmitted radiation results in an own luminance of the solar protection device, which
v, dir-dif
appears as a light source.
This may constitute a discomfort factor, either from an excessive value of the luminance in itself, or from the
contrast between the luminance of the solar protection device and that of its surrounding.
Solar protection devices shall be classified, with regard to the following criteria:
opacity control;
glare control;
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night privacy;
visual contact with the outside;
daylight utilisation;
rendering of colours.
These criteria depend on three main optical factors:
τ normal/normal light transmittance;
v, n-n
τ diffused part of light transmission;
v, n-dif
τ diffuse/hemispherical light transmittance.
v, dif-h
The performance classes for glare control, night privacy, visual contact with the outside, daylight utilisation are
quoted in Table 5.
Table 5 — Definition of Classes
Influence on visual comfort
0 1 2 3 4
Class
very good
very little effect little effect moderate effect good effect
effect
NOTE 1 The real light transmittance of the solar protection device may be much greater than that of the curtain, due to the
lateral gaps and the guiding system. It is difficult to establish, either by calculation or direct measurement.
NOTE 2 The residual light transmittance of the solar protection device in its fully extended and closed position can be
evaluated, according to the type of solar protection device, from the light transmittance of the constitutive materials. To some
extent, the light transmittance of a completely closed or partially opened slatted or louvered device (e.g. venetian blind) can be
evaluated using the calculation method given in EN 13363-2 from the light characteristics and geometry of the slats or laths.
NOTE 3 When the window is not directly exposed to the sun it receives diffuse radiation, which may be disturbing enough to
require that the solar protection device remains in the extended position.
NOTE 4 Health and safety regulations require that the workplace receives as much natural light as is reasonably practical
(see EU Directive ED 89/654 EEC).
NOTE 5 All retractable products provide a certain degree of adjustment of natural light (see EU Directive ED 89/654 EEC).
NOTE 6 Adjustable slatted products provide optimal light control.
NOTE 7 In the case of a venetian blind with unperforated slats, τ can be considered as 0 when the blind is fully closed. If
v, n-n
the slats can be tilted horizontally, τ can be considered to be greater than 0,5 in that position. This means, that τ of a
v, n-n v, n-n
venetian blind with unperforated slats can be adjusted to a large extent.
NOTE 8 In the case of a venetian blind with fully perforated slats, the minimum value of τ can be considered to be the
v, n-n
measured value of τ of the perforated area of an individual slat
...
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