Retroreflective Materials on Working Cloths Application Guidelines
Coefficient of retroreflection R' of a sample is determined for the rotation angles e=0 and e=90° with the viewing angle of 12' and the incidence angle of 5°. Position e=0 is determined with a special marking on each sample or according to the instructions of the material’s manufacturer. In cases when there are no markings or instructions, position e=0 is selected randomly.
Determination of Retroreflective Characteristics after Life Testing.
Resistance to Abrasion.
Sample is tested against the abrasion with the woolen cloth according to the methods of the Standard prEN N530, Method 2. Measurements are taken after 5000 cycles.
Resistance to Bending.
Sample is tested against bending according to the methods of the Standard ISO N4675, Method A.
Measurements are taken after 7500 cycles.
Resistance against Bending in the Cold.
Sample is held and tested against bending according to the methods of the Standard ISO N4675 at the temperature of -20(±1)°C.
Measurements are taken after returning to normal conditions according to Par. 3.2 during at least two hours.
Resistance to Temperature Difference.
Samples with the dimensions of 180х30 mm go through the continuous temperature cycle in the following order:
a) 12 hours at the temperature of 50(±2)°С, then an immediate transition to
b) 20 hours at the temperature of -30(±2)°С, then an immediate transition to
c) c) normal conditions according to Par. 3.1 during at least two hours.
Resistance to Washing and Chemical Cleaning.
If the labels on the clothes indicate that washing is possible, the procedure described in
Par. 184.108.40.206 is used. If the labels on the clothes indicate that chemical cleaning is possible, the procedure described in Par. 220.127.116.11 is used. If the labels on the clothes indicate that both washing and chemical cleaning are possible, procedures described in Par. 18.104.22.168 and Par. 22.214.171.124 are performed separately on different samples of material.
Washing According to Handling Directions
For testing, we use three samples with the dimensions of 300x250 mm that have two stripes of the retroreflective material measuring 250х50 mm located 50 mm apart from each other.
Washing of samples is performed according to the methods of the Standard ISO 6330, Method 2A.
Specified washing cycle is performed as many times as indicated on the label. At the end of the last cycle, samples are dried in a loose position at the temperature of 50(±5) °C.
Chemical Cleaning According to Handling Directions.
Testing samples are prepared according to Par. 126.96.36.199. Chemical cleaning of samples is performed according to the methods of the Standard ISO 3175, Method 9.1, as many times as indicated on the label.