| There were two proposals under discussions concerning the set-up of the seat for the measurement of height and backset. |
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| The issues of backset limits and the evaluation of active head restraints are interrelated. |
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| With a smaller backset, the rearward head motion was stopped earlier by the head restraint, resulting in a smaller head to torso displacement. |
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| When these systems are in their normal drivng position, they may have a larger static backset. |
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| The United States of America is currently the only country that specifies use of the H-point for static measurements other than backset. |
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| The computer modelling indicates that the lowest head-to-torso rotation value was seen when the backset was approximately 50 mm. |
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| The adjustable head restraints are measured in any height and backset position of adjustment. |
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| Some experts disagree with this concept stating that it would eliminate adjustable backsets and that the head restraint already has to meet the backset requirement. |
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| The test for adjustable head restraints incorporates both the evaluation for total displacement of the head restraint and the evaluation of the locking mechanism for the adjustable backset. |
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| In any event, no evidence has been presented that a substantial number of drivers are dissatisfied with the backset of the head restraints in half of all vehicles. |
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| A proposal was made to incorporate in the gtr a test procedure that combines the displacement test evaluation with an evaluation of adjustable backset locking systems. |
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| However, to be taken into account as a valid point for the outer edge of the front contact surface, a point must be no further rearwards than the maximum allowed backset for the concerned designated seating position. |
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| It argued that this more upright back angle greatly reduces the backset to the point it interferes with the head of some of these occupants, not just the hair. |
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| Others proposed a less stringent backset of 70 mm. |
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