Bsi bs en 02155 5 1989 (1999)

BRITISH STANDARD AEROSPACE SERIES BS EN 2155 5 1989 Test methods for transparent materials for aircraft glazing — Part 5 Determination of visible light transmission This European Standard EN 2155 5 ha[.]

This European Stand rd EN 2 5 -5 has the status of a

British Stand rd

U C 6 9.7 0 3.2 :6 0.1:5 5.3 5.1 – 2

This British Stan ard,ha ing

b en pre ared u der the

directionof the Aerosp ce

Stan ards Polcy Commite ,

waspublshed u der the

authority f the Bo rd of BSI

an comes into efect on

3 Octo er1 8

© BSI 0 -1 9

The folowing BSI references

relate to the work on this

stan ard:

Commite reference ACE/62

Draft for comment 8 /70 0 DC

ISBN 0 5 0 1 9 0 3

The European Commit e for Stand rdization, u der whose superv ision this

European Stand rd was prep red, comprises the national stand rds

org anizations of the fol owing W estern European cou tries

Belg ium Institut belg e de normalsation

Finland S omen Stand rdisoimisl ito, r.y

France Association fançaise de normal sation

Germany Deuts hes Institut für Normu g e.V

Gre ce Hel enic Org anization for Stand rdization

I eland I elandic Counci for Stand rdization

I eland National Stand rds Authority of I eland

Italy Ente Nazionale Italano di Unificazione

Luxemburg Inspection des trav ai s et des Mines

Netherlands Nederlands Normalsatie-nstitu t

Portug al Instituto Portug uês d Quald de

Sweden Stand rdisering skommis ionen i Sv erig e

Switz rland Association suis e de normal sation

United King dom British Stand rds Institution

Am endm ents is ued sinc publ cation

Amd No Date of is ue Comments

Pag e

National foreword

This British Stand rd has be n prep red u der the direction of the

Aerosp ceStand rds Pol cy Commit e and is the Eng lish lang uag e v er ion

ofEN2 5 “A er ospa ce s r ie Te t method s fr tr a nspa r ent ma ter ia ls fr a ir cr a ft

gla zing” Part5 “Deter mina tion o visible light tr a nsmis ion” publshed b the

European Commit e for Stand rdization ( CEN) EN2 5 -5 was produced as a

result of international dis us ion in which the UK to k an activ e p rt

A British Stand rd do s not purport to include al the neces ary prov isions of a

contract User of British Stand rds are responsible for their cor ect a pl cation

Com pl anc with a British Standard do s not of itselfc nfer im munity

f om leg al obl g ations

Summ ary of pag es

This document comprises a font cov er, an inside f ont cov er, p g es i and i,

theEN title p g e, p g es2 to6, an inside b ck cov er and a b ck cov er

This stand rd has be n up ated ( se cop rig ht d te) and ma hav e ha

amendments incorporated.This wi be indicated in the amendment ta le on the

inside f ont cov er

NORME EUROPÉENNE

Mar h 1 89

UDC: 6 9.7 0 3.2 :6 0.1:5 5.3 5.1-2

Ke words:Air raft in ustry,g lazing , transp rent plastic , g las ,test, o tical pro erties

Eng lish ver ion

for aircraft g lazing

Série aérosp tiale Méthodes d’es ais pour

matériaux transparents pour vitrag es

aéronautiques

Partie 5: Mesure de la transmis ion orig inale

dans le visible

Luft- und Raumfahrt Prüfv er ahren für

transp rente W erkstofe zur Verg lasung

vonLuftfahr eug en

Tei 5: Mes ung des Licht ransmis ions-

gra esim sichtbaren Bereich

This European Stand rd was ac epted b CEN on 19 8-0 -17 CEN member

are bou d to comply with the requirements of CEN Internal Reg ulations which

stipulate the conditions for g iv ing this European Stand rd the status of a

national stand rd without any alteration

Up-to-d te lsts and bibl og ra hical references concerning such national

stand rds ma be obtained on a pl cation to the CEN Central Sec etariat or to

any CEN member

This European Stand rd exists in thre oficial v er ions ( Eng lish, French,

German) A v er ion in any other lang uag e ma e b translation u der the

responsibi ity of a CEN member into its own lang uag e and notified to CEN

Central Sec etariat has the same status as the oficial v er ions

CEN member are the national stand rds org anizations of Austria, Belg ium,

Denmark, Finland, France, Germany , Gre ce, I eland, I eland, Italy ,

Luxemburg , Netherlands, Norway , Portug al, Sp in, Sweden, Switz rland and

UnitedKing dom

European Commit e for Stand rdization

Comité Europé n de Normalsation

Europ is hes Komite für Normu g

Central Se retariat: rue de Stas art 3 , B- 10 0 Brus els

© CEN 19 9 Copy rig ht reserv ed to al CEN member

Ref No EN 2 5 -5:19 9 E

This European Stand rd has be n prep red b the

European Association of Aerosp ce Man facturer

( AECMA)

After enquiries and v otes car ied out in ac ord nce

with the rules of this Association, this Stand rd has

suc es iv ely receiv ed the a prov al of the National

Associations and the Oficial Serv ices of the member

cou tries of AECMA, prior to its presentation to

CEN

According to the Common CEN/ CENELEC Rules,

fol owing cou tries are bou d to implement this

European Stand rd: Austria, Belg ium, Denmark,

Finland, France, Germany , Gre ce, I eland,

I eland, Italy , Luxemburg , Netherlands, Norway ,

Portug al, Sp in, Sweden, Switz rland and the

UnitedKing dom

Contents

Pag e

1 Scope and field of a plcation 3

Fig ure 2 — Piv ota le-sphere haz meter 5

1 Scope and field ofappl cation

This stand rd specifies the determination of v isible

l g ht transmis ion for transp rent materials b

using a photometer employ ing a defined lg ht sour e

and a photocel matched to the response of the

human ey e

Because the materials u der test are b sical y

colourles , certain dev iations fom ideal conditions,

indicated in the test, are alowa le

2 Definitions

Visible l g ht transmis ion is defined as the intensity

of an emerg ing beam of l g ht comp red with that of

the incident p ralel beam fal ing upon the

specimen u der ex mination

The a p ratus shal consist of a haz meter,

constructed es entialy as shown in Fig ure 1 or

Fig ure 2 It consists of a sta i sed l g ht sour e and

as ociated optical sy stem, specimen holder and

photometer al rig idly mounted on a conv enient

optical bench The distance of the photometer f om

the i luminated area of the specimen shal not be

les than25 mm in order to av oid spurious sig nals

f om s at ered l g ht

3.1 Light sour ce

3.1.1 The lg ht sour e is a tu g sten fi ament lamp

operated at a colour temperature of ( 2 8 5±28 ) K

This wi be at ained b using a g as fi ed tu g sten

fi ament lamp operating at its rated v oltag e

3.1.2 The power sup ly to this lamp shal be

sta i z d The short term chang e in v oltag e output

shal not be more than ± 0,1%

3.1.3 The lg ht sour e is combined with an optical

system to produce a p ralel lg ht beam of area at

least1cm

2

3.2 Photometer

This shal be a suita le photocel fit ed with

difusion s re n or integ rating sphere

3.2.1The spectral response of the photocel shal be

cor ected to a proximate that of the h man ey e For

practical purposes this cor ection ma be l mited to

ensuring that no substantial response exists bey ond

the v isible b nd A selenium/iron photocel with a

g re n fite is satis actory for this purpose

3.2.2 The output response of the photocel shal be

l near within ± 0,5%

3.2.3 The output of the photocel shal be rea on a

suita le measuring instrument of ± 0,5%ac uracy

3.2.4 The photocel shal be fit ed with a difusion

s re n and both shal be of a equate dimensions to

completely cov er the p ral el l g ht beam produced

b the lg ht sour e

3.3 Spe imen hol d er

The specimen holder shal be such as to hold the

specimen rig idly in a plane normal to the lg ht

beam

3.4 Us o integr a ting spher e

It ma be conv enient to use a photometric

integ rating sphere in place of the photometer

des ribed in3.2 In which case the a p ratus ma

be constructed es ential y as shown in Fig ure 1 or

Fig ure 2

3.4.1 Integr a ting spher e

An integ rating sphere is used to col ect transmit ed

flux The sphere ma be of any diameter so long as

the total port area do s not ex ce d4%of the

internal reflecting area of the sphere

The entrance and exit ports shal be centred on the

same g reat cir le of the sphere and there shal be at

least17 ° of ar betwe n centres The exit port shal

subtend an ang le of8° at the centre of the entrance

port The a is of the ir a iating beam shal p s

throug h the centres of the entrance and exit ports

The photocel or photocels shal be positioned on the

sphere ( 90 ± 10)° fom the entrance port In the

piv ota le model, Fig ure 2, which is desig ned to use

the interior sphere wal a jacent to the exit port as

the reflectance stand rd, the ang le of rotation shal

not exce d10°

3.4.2 Light bea m

The specimen shal be i uminated b a

substantial y u idirectional beam; the ma imum

ang le which any ra of this beam makes with the

direction of its a is shal not exce d3° The beam

shal not be v ig net ed at either port of the sphere

W hen the beam is u obstructed b a specimen, its

c os section at the exit port shal be a proximately

cir ular, sharply defined and concentric within the

exit port, leav ing an an ulus of ( 1,3 ± 0,1)°

subtended at the entrance port W hen the specimen

is placed immediately ag ainst the integ rating

sphere at the entrance port, the ang le betwe n the

normal to its sur ace and the a is of the beam shal

not exce d8°

3.4.3 R eflectng sur fa ce

The suraces of the interior of the integ rating

sphere, b fles and reflectance stand rds shal be of

substantial y equal reflectance, mat and hig hly

reflecting throug hout the v isible wav e leng ths

( freshly smoked mag nesium oxide is excelent for

this purpose but hig hly reflecting mat sphere

p ints are more dura le)

3.4.4 Light tr a p

For some measurements the stand rd at the exit

port is replaced b a l g ht tra b actual remov al of

the reflectance stand rd or b piv oting the sphere

( se Fig ure 2) The l g ht tra shal a sorb the beam

completely when no specimen is present

Due to the a sorbing an ulus sur ounding the

u impeded beam at the exit port, this tra wi l

a sorb slg htly more than the u dev iated portion of

the total flux transmit ed b the specimen

3.4.5 Photoelectr ic c ll

The ra iant flux within the sphere shal be

measured b a photo lectric cel , the output

measurements of which shal be proportional

within1 %to the incident flux ov er the rang e of

intensity used Spectral conditions for sour e and

receiv er shal be constant throug hout the test of

each specimen

The desig n of the instrument shal be such that

there shal be a z ro rea ing when the sphere is

d rk.The spectral response of the photocel shal be

cor ected to a proximate that of the h man ey e

3.4.6 Clauses3.2.1,3.2.2and3.2.3a ply to the

photocel used in conjunction with the integ rating

sphere

4 Specim ens

Specimens shal be cut fom she ts with the

sur aces substantialy flat and p ralel

5 Procedure

5.1The specimen shal be cleaned with soa y water

on both sur aces before measurements are ma e

5.2 The a p ratus is alowed suficient time to reach

thermal equi brium before the measurements are

ma e

5.3 The measurements shal be ma e with the lg ht

beam normal to the surace of the specimen and the

av erag e taken fom thre independent

measurements on the one specimen

5.4 A fir t rea ing ( a) of the photometer output shal

be ma e with the specimen outside of the beam

5.5 A second rea ing ( b) shal be ma e with the

specimen interposed betwe n the l g ht sour e and

photometer ( specimen-photometer distance at

least25 mm)

5.6 The thick es of the specimen shal be measured

in thre places to an ac uracy of0,02 mm

6 Expres ion ofresults

The per entag e of v isible lg ht transmis ion is

calculated fom the formula:

% v isible lg ht transmis ion =

7 Test r port

The test report shal include the folowing :

7.1 The per entag e of v isible l g ht transmis ion as

the av erag e of thre calculated results,

7.2 The thick es of the specimen as the arithmetic

av erag e of the thre measurements

b

a

- 10

Fig ure 1 — Hazem eter

Fig ure 2 — Pivota le- sphere hazemeter

National appendix A

The United King dom p rticip tion in the prep ration of this European Stand rd was entrusted b the

Aerosp ce Stand rds Polcy Commit e ( ACE/-) to Tech ical Commit e ACE/62 upon which the folowing

bodies were represented:

British Plastic Federation

Ministry of Defence

Society of British Aerosp ce Comp nies Limited

3 9 Chiswick Hig h Roa

London

W 4 4AL

BSI is the independent national bod responsible for prep ring

BritishStand rds It presents the UK v iew on stand rds in Europe and at the

international lev el It is incorporated b Roy al Charter

Revisions

BritishStand rds are up ated b amendment or rev ision User of

BritishStand rds should make sure that they pos es the latest amendments or

editions

It is the constant aim of BSI to improv e the qualty of our products and serv ices

W e would be g rateful if any one finding an inac uracy or ambig uity whie using

this BritishStand rd would inform the Sec etary of the tech ical commit e

responsible, the identity of which can be fou d on the inside f ont cov er

Tel:0208 9 9 0 Fa : 0208 9 7 0

BSI ofer member an indiv idual up ating serv ice cal ed PLUS which ensures

that subs riber automatical y receiv e the latest editions of stand rds

Buying standards

Order for al BSI, international and foreig n stand rds publ cations should be

a dres ed to Customer Serv ices Tel:0208 9 9 01 Fa : 0208 9 7 01

In response to order for international stand rds, it is BSI polcy to sup ly the

BSI implementation of those that hav e be n publshed as BritishStand rds,

u les otherwise requested

Inform ation on standards

BSI prov ides a wide rang e of information on national, European and

international stand rds throug h its Library and its Tech ical Help to Ex orter

Serv ice.V arious BSI electronic information serv ices are also av ai a le which g iv e

detai s on al its products and serv ices Contact the Information Centre

Tel:0208 9 71 1 Fa : 0208 9 7 4

S bs ribing member ofBSI are kept up to d te with stand rds dev elopments

and receiv e substantial dis ou ts on the pur hase price of stand rds For detais

of these and other benefits contact Member hip Administration

Tel:0208 9 7 02 Fa : 0208 9 7 01

Copyrig ht

Copy rig ht subsists in al BSI publ cations BSI also holds the copy rig ht, in the

UK, of the publcations of the international stand rdization bodies Except as

permit ed u der the Copy rig ht, Desig ns and Patents Act 19 8 no extract ma be

reproduced, stored in a retriev al sy stem or transmit ed in any form or b any

means – electronic, photocopy ing ,recording or otherwise – without prior writ en

permis ion f om BSI

This do s not preclude the f e use, in the cour e of implementing the stand rd,

of neces ary detais such as sy mbols, and siz , ty pe or g ra e desig nations.I these

detai s are to be used for any other purpose than implementation then the prior

writ en permis ion of BSI must be obtained

I permis ion is g ranted, the terms ma include roy alty p y ments or a l censing

ag re ment Detai s and a v ice can be obtained fom the Cop rig ht Manag er

Tel:0208 9 7 7