Document ID: chunk:federal_register_of_legislation:F2015C00542:reg:52:p6
Version: federal_register_of_legislation:F2015C00542
Segment Type: reg
Provision Reference: reg 52 (pt 6/6)
Character Range: 98994–100773

the cross arm's fall is dampened and the phantom head falls onto the sample.

               No impulse may be given to the phantom head by the drop appliance or by the measuring cable, so that it is accelerated only by gravity and falls vertically.

Figure 2.2

Test apparatus for the headform experiment with deceleration measurement

              3.2.2.1. Measuring device which allows determining HIC-values with the headform described under paragraph 3.2.1.

              3.2.2.2. Equipment to calibrate the phantom head

               The drop appliance shall allow drop heights between 50 mm and 254 mm to be adjusted exactly to within 1 mm. A guide system is not necessary for these small drop heights.

               A steel impact plate which is made of steel is 600 mm x 600 mm in size and at least 50 mm thick. The impact surface shall be polished:

                surface roughness Rmax = 1 m, flatness tolerance t = 0.05 mm.

              3.2.2.3. Calibration and adjustment of the phantom head

               Before each test series and no later than each 50 tests within a series, the phantom head shall be calibrated and adjusted if necessary.

               The impact plate shall be clean and dry and during the test shall lie non-positively on a concrete base.

               The phantom head is allowed to hit the impact plate vertically. The drop heights (measured from the lowest point of the phantom head to the surface of the impact plate) are 50, 100, 150 and 254 mm. The deceleration curves should be recorded.

               The greatest deceleration az from the various drop heights on the z-axis shall lie within the limits given in the table:

Drop height mm  Greatest deceleration az as a multiple of acceleration due to gravity g