7.1 Sampling and conditioning
Samples for testing shall be taken from the original device or from the retroreflective or fluorescent material as used in the garment or a device. The size, shape and quantity shall be as required for each test procedure.
Unless otherwise specified, one specimen of each material shall be tested and shall comply with the minimum requirements before and after exposure.
The specimens shall be conditioned for at least 24 h at (20± 2)C and (65±5) % relative humidity. If the test is carried out in other conditions, the test shall begin within 5 min after withdrawal from the conditioning atmosphere.
7.2 Determination of colour
The colour shall be measured in accordance with the procedures defined in CIE 015:2018, using an instrument with polychromatic illumination (CIE D65 illuminant).
The instrument shall have a 45/0 illuminating and viewing geometry. The colour coordinates shall be determined using CIE standard illuminant D65 and 2°standard observer (CIE 1931= standard colourimetric observer). The specimen shall be measured with a single layer including any backing or lining used in its constructions and backed by a black underlay with a reflectance of less than 0,04. At least four measurements shall be carried out in four perpendicular directions and the mean value shall be given as the test result.
NOTE lf the instrument is known to be either an annular or circumferential type, only one reading can be performed
7.3 Method of determination of retroreflective photometric performance7.3.1 General
The photometric performance shall be determined in accordance with the procedure defined in CIE 54.2:2001.
7.3.2 Type B1 devices
Samples for measurement shall consist of the original device. Each colour shall be tested separately. When a family of devices is manufactured, testing can be performed only on the smallest presented product and on the colour with the lowest photometric values.
For the other products, only the optically active area shall be calculated and be larger than the one of the approved product.
All area covered by print that influences the performance of the final product shall be treated as non-retroreflective even if it is transparent colours and deducted from the total area.
7.3.3 Type B2 and B3 and Type AB devices or garments
Samples for measurement shall consist of one piece of retroreflective material (100 ×100) mm or multiple retroreflective elements as used on finished garment or device, combined and mounted flat side by side as close as possible to form an area of (100 × 100)mm or width of the item in a length of10 cm or in size of specimen of the exposure treatment.
lf the retroreflective elements exhibit the presence of logos or printings or other cosmetic enhancements, the selection of the retroreflective element shall be made on the lowest performing segment with respect to the retroreflective performance. lf it is determined that no such logos or printings or custom markings exist, the selection of samples shall be made at random.
The lowest-performing segment shall be identified visually and confirmed by preliminary photometricassessments.Each of the segments combined to form an area of (100 ×100)mm shall consist of the lowest-performing segment.
R for the sample shall be measured at two positions of the rotation angle e, 0° and 90° and at anobservation angle of 12′ with an entrance angle of 5. The position 0° is determined by one of the following means:
-a clear datum mark on each sample;
– a clear instruction given by the manufacturer of the material;
– lf no mark or instruction exists, the position e = 0°can be chosen at random.