1、STD.AECMA PREN 2155-4-ENGL 2000 m LO12311 OUL858 525 Edition approved for publication 2000-10-31 AECMA STANDARD NORME AECMA AECMA NORM Comments should be sent within six months after the date of publication to AECMA Gulledelle 94 B-1200 BRUXELLES prEN 21 55-4 Edition P 1 October 2000 PUBLISHED BY TH
2、E EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - 6-1200 BRUXELLES - Tel. (+32) 2 775 81 1 O - Fax. (+32) 2 775 81 11 Supersedes edition 1 March 1980 ICs: Descriptors: ENGLISH VERSION Aerospace series Test methods for transparent materials for aircraft glazing Part 4 - Determina
3、tion of ultraviolet light transmission over the wavelength range 280 nm to 360 nm Srie arospatiale Luft- und Raumfahrt Mthodes dessais pour matriaux transparents pour vitrages aronautiques Partie 4 - Dtermination de la transmission des rayons ultraviolets de 280 nm 360 nm Prfverfahren fr transparent
4、e Werkstoffe zur Verglasung von Luftfahrzeugen Teil 4 - Bestlmmung des Transmisslonsgrads fr Ultraviolett-Strahlung im Bereich von 280 nm bis 360 nm This “Aerospace Series“ Prestandard has been drawn up under the responsibility of AECMA (The European Association of Aerospace industries). It is publi
5、shed on green paper for the needs of AECMA- Members. It has been technically approved by the expetfs of the concerned Technical Committee fol/owing comment by the Member countries. Subsequent to the publication of this Prestandard, the technical content shall not be changed to an extent that interch
6、angeability is affected, physically or functionally, without re-idenfification of the standard. Affer examination and signature of the AECMA Standard Checking Centre (NPS) and formal agreement of the Official Services of the Member countries it will be submitted as a draff European Standard to CEN (
7、European Committee for Standardization) for formal vote. Nota - Extra copies can be supplied by B.N.A.E. - Technopolis 54 - 199. rue Jean-Jacques Rousseau - 92138 ISSY-LES-MOULINEAUX CEDEX I I C7 Chairman Mr Wright I I aecma 200 Page 2 prEN 21 55-4: 2000 Contents . Scope 3 Definition 3 Apparatus 3 3
8、 Test specimens . Procedure . 4 Test Report . 4 Page 3 prEN 21 55-4: 2000 1 Scope This standard specifies the method to determine the determination of ultraviolet light transmission of transparent materials over the wavelength range 280 nm to 360 nm. 2 Definit ion For the purpose of this standard th
9、e following definition applies: Ultraviolet light transmission is the intensity of an emerging beam of ultraviolet light compared with that of the incident parallel beam falling on the specimen under examination. 3 Apparat us 3.1 Light source The light source shall be capable of producing a continuo
10、us ultraviolet spectrum over the wavelength range 280 nm to 360 nm, and shall preferably operate at low pressure to avoid errors caused by broadening of emission lines. Deuterium lamps have been found suitable. 3.2 Spectrophotometer The spectrophotometer shall be equipped to record transmittance aut
11、omatically in the spectral region 280 nm to 360 nm with a spectral slit of 1 nm. Wavelength measurements shall be repeatable, and known, to an accuracy of f 0,25 nm as measured by a mercury emission line at 31 3,16 nm. The photometric response of the apparatus shall be accurate to within 0,5% when d
12、etermined with at least three samples whose transmittance has been accurately measured by a suitably accredited standardising laboratory. Suitable samples for this purpose are standardised metal-on-quartz filters or solutions of potassium dichromate in perchloric acid. 3.3 Calibration Wavelength cal
13、ibration shall be carried out prior to test using the emission spectrum of a low pressure mercury arc and the absorption spectra of holmium oxide glass (2 mm to 4 mm thick) or holmium oxide solution (4 /O (wh) solution in 1,4 M perchloric acid). 4 Test specimens Three specimens, of a suitable size t
14、o fit the equipment used, shall be cut from each sheet and shall have clean surfaces free from scratches and other imperfections. Page 4 prEN 21 55-4: 2000 5 Procedure Prior to test, the specimens shall be conditioned at (23 i 2) “C and (50 i 5) % relative humidity for (24 f 1) h. Measurements shall
15、 be made with the ultraviolet light beam normal to the surface of the specimen and each measurement shall be an integration of the transmission over an area of the specimen of at least 1 cm2. The measurements shall be made using a spectral band-width of f 2 nm over the wavelength range specified. Wh
16、en using a recording double beam spectrophotometer, it is only necessary to position the specimen in the specimen compartment and to record the transmission over the range specified. When using a single beam non-recording spectrophotometer, individual readings have to be made with and without the sp
17、ecimen in position and the transmission factor calculated from the result. The thickness of the specimen shall be measured and recorded, to an accuracy of f 0,2 mm, in close proximity to the area where the transmission has been measured. 6 Test Report The test report shall include the following: - r
18、eference to this standard; - material type and thickness of each specimen; - the batch number; - a spectrum showing the percentage ultraviolet light transmission over the specified wavelength range, for each specimen; - the integrated ultraviolet transmission, in percent, over the specified wavelength range, if requested by the customer.
