Document ID: chunk:federal_register_of_legislation:F2019C00042:front:0:p32
Version: federal_register_of_legislation:F2019C00042
Segment Type: other
Provision Reference: 
Character Range: 87160–89926

the normal conditions of use, at a rate of approximately 100 mm/s and the maximum force measured to the nearest 0.1 daN after the first 25 mm of strap movement. The test shall be carried out in both directions of strap travel through the device, the strap being cycled 10 times prior to the measurement.

         7.6. Additional tests for safety-belts with retractors

         7.6.1. Durability of retractor mechanism

         7.6.1.1. The strap shall be withdrawn and allowed to retract for the required number of cycles at a rate of not more than 30 cycles per minute. In the case of emergency locking retractors, a snatch to lock the retractor shall be introduced at each fifth cycle.

          The snatches shall occur in equal numbers at each of five different extractions, namely, 90, 80, 75, 70 and 65 per cent of the total length of the strap remaining wound on the retractor. However, where more than 900 mm is provided the above percentages shall be related to the final 900 mm of strap which can be withdrawn from the retractor.

         7.6.1.2. A suitable apparatus for the tests specified in paragraph 7.6.1.1. above is shown in Annex 3 to this Regulation.

         7.6.2. Locking of emergency locking retractors

         7.6.2.1. The retractor shall be tested once for locking when the strap has been unwound to full length less 300 + 3 mm.

         7.6.2.1.1. In the case of a retractor actuated by strap movement, the extraction shall be in the direction in which it normally occurs when the retractor is installed in a vehicle.

         7.6.2.1.2. When retractors are being tested for sensitivity to vehicle deceleration they shall be tested at the above extraction along two perpendicular axes, which are horizontal if the retractor is installed in a vehicle as specified by the safety‑belt manufacturer. When this position is not specified, the testing authority shall consult the safety‑belt manufacturer. One of these axes shall be in the direction chosen by the Technical Service conducting the approval test to give the most adverse conditions with respect to actuation of the locking mechanism.

         7.6.2.2. A suitable apparatus for the tests specified in paragraph 7.6.2.1. above is described in Annex 4 to this Regulation. The design of any such test apparatus shall ensure that the required acceleration is given before the webbing is withdrawn out of the retractor by more than 5 mm and that the withdrawal takes place at an average rate of increase of acceleration of at least 55 g/s 8/ and not more than 150 g/s [8]/ in testing sensitivity for strap movement and of at least 25 g/s 8/ and not more than 150 g/s 8/ in testing sensitivity for vehicle deceleration. 8/

         7.6.2.3. To check conformity with