Filters and eye-protectors against laser radiation (laser eye-protectors)

Filters and eye-protectors against laser radiation (laser eye-protectors)

BS EN 207:1999 pdf free.Personal eye-protection一 Filters and eye-protectors against laser radiation (laser eye-protectors).
The spectral tnmsmittance for the laser wavelength shall, however, in no case exceed the maximum sIw(lral traii.siiiiltance corresponding to the indicated scale number.
3.7 Resistance of filters and frames to ignition When tested in accordance with 4.7, the filters and frames shall not ignite or continue to glow.
3.8 Field of vision of eye-protectors Eye-protectors shall have a clear field of vision of at least 400 in the vertical and horizontal directions for each eye when measured in accordance with 4.8 (see FIgure 1).
3.9 ConstructIon of filters
Filters shall be constructed so that when tested in accordance with 4.3 and 4.9 no splinters are detached from the side of the filter lacing the eye. If the filters consist of several individual ifiters, they shall be assembled in such a way (hat they cannot be interchanged.
3.10 Frames
Filters shall no4 be interchangeable in the frame. The frame shall be (lesigned so (hat no laser radiation can penetrate from the side unintentionally.
3.11 Mechanical strength of eye-protectors
3.11.1 Bade requirement
Filters for protection against laser radiation shall be of at least 1,4 mm hickness or satisfy the static bending requirement as specified in 7.1.4.1 of EN 166:1995. The frames of the eye-protectors shall satisfy the requirements of 7.1.4.2 or 7.2.2 of EN 166:1995. 3.11.2 Optional requirenients
If the mechanical strength of filters and eye-protectors against laser radiation is to satisfy more stringent requirenwnls, the requiremenis specified in 7.1.4.2 or the requirements specified in 7.2.2 of EN 166:1995 shall be met.
4 Thsting
The testing schedule in Table 3 shall be applied to te testing of filters, frames and complete eye-pmtectors. 11w sequence of testing 1 to 9 may be changed. The sequence of testing 1310 16 may be changed. At least 16 filters or 8 complete eye-protectors are required for esting. If testing for several wavelengths (wavelength ranges) or testing conditions according to 4.3 and/or several optional requirements has to be (lone. iiiore thu 16 samples may be necessary
4.1 Spectral transmittance of fllters and frames The spectral transmittance shall be determined for normal incidence. Filters with angular-dependent transmittance (such as interference layers) for the wavelength range from 400 nm to 1 400 nni shall he measured at angles of incidence between 00 antI 300 with poLazized radiation, FIlters with angular-dependent transmittance for other wavelengths shall he measured at angles of incidence between 0° and 900 with polarized radiation. In this case, the scale number results froiu the highest of the spectral truisnuttuiee values measured.
4.2 Luminous transmittance of filters
The luininou,s tnusmittanee shall be (lelernuned for flonual ulci(leLIce. relative to the D6.5 S1.UKLIUI ifluminant (see ISO’CIE 10626:1991 and ISO/CIE 10627:1991).
4.3 Stability of filters and frames to laser radiation The test shall be carried out with laser radiation of the specified wavelengths and the power and energy densities given in Table 1. The spectral transmittance shall be measured for each laser wavelength during the course of irradiance. The frame shall be exposed to radiation at the point of least thickness for each of the materials used (with the exception of headbands). The diameter of the laser beam during this test shall be≥0,1 mm.The duration of the test shall be taken from Table 4.
NOTE The pulse lengths for test conditions I and R do not follow consecutively. Neither are they a continuation of the length for test condition D. The pulse lengths indicated are characteristic values of typical lasers. It is reconuuended to use a laser with a pulse length in this range.
All laser radiation protective filters shall be tested in accor(Iance with the test con(ht ion D. If no CW laser is available for a specific wavelength, a pulse laser at a minimum pulse repetition frequency of 5 Hz may be used.
if additional protection against pulsed lasers is required, the filters and laser radiation eye-protectors shall be tested according to one or several of the test conditions I, R, or NI.
4.4 Refractive value of filters and
eye-protectors
The test shall be earned 0111 in accordance with
clause 3 of EN 167:1995.
4.5 Quality of material and surface of filters
4.5.1 Material and surface defects
The test shall 1w earned 0111 in accordance with clause 5 of EN 167: 1995.
NOTE The thin layered filters should be very carefully examined, as the protection could be affected if the vacuum deposited layer were damaged (e.g. by scratches and holes).
4.5.2 Scattered light
The test shall be carried out in accordance with clause 4 of EN 167:1995.
4.6 Stablilty to UV radiation
The test shall be carried out in accordance with clause 6 of EN 168:1995, with the huup finning at a power of 450 W and an exposure time of (54) ± 0,2) Ii.
4.7 Resistance of filters and frames to ignition The test shall be earned out in accordance with clause 7 of EN 168:1995,
4.8 Field of vision of eye-protectors For measuring the field of vision, the test head specified in EN 168:1995 with the eye-protector without titters shall be mounted as shown in the example of set up illusirated in Figure 1 so that the two axes of rotation A and B and the optical axis C intersect in the middle of the front surface of one eye, Radiation is provided by a laser beam of niaxinumi diameter 5 mm along axis C, for example. When rotated around axis A, the difference in the angular positions at which the light beam no longer hits the eye gives the vertical field of vision. By rotating around axis B, the (lifference between the angular position at which the light beam no longer hits the eye and the line of vision of the test head parallel to the optical axis C gives half the horizontal field of vision.
Other methods are permissible if they give identical results.
4.9 ConstructIon of filters
The test shall be carried out by mean.s of visual insjwctioii
4.10 Frames
The frames shall be tested by means of visual inspection.
4.11 MechanIcal strength
The test shall be eanied out in accordance with clause 4 of EN 168:1995.
5 Information supplied by the
manufacturer
The information shall be in the language(s) of the country in winch the eye—protector is sold.
The selection cntena and iiistflictions for use shall contain at least the following data
a) luminous tran.smittance;
b) if the hnninous transmittance is less than 20 %, this shall be indicated an(I the user shall be recommended to increase the intensity of illumination at the workplace;
c) in the case of tinted filters a warning to the user to check if the recognition of warning lights or warning signals is impaired;
d) the information that eye—protectors are only intended to give protection against accidental radiation and that both the limiting values and the stability tests are based on a maximum period of lOs;
e) the information that eye-protectors and filters against laser ra(hation which have l)een damaged or which have undergone a colour change should not be used any more;
1) an explanation of the symboLs used in the marking;
g) the note that the limiting values as specified in annex A have been simplified on the safe side compared with the limiting values in EN 60825-1:1994. If the user wishes to use the EN 60825-1:1994 values, he shall carry out a special test to see whether the stability of the eye-protectors against laser radiation is a(lequate for the specified application;BS EN 207 pdf free download.Filters and eye-protectors against laser radiation (laser eye-protectors)

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