92 Ergonomics in the Automotive Design Process
gauges such as the speedometer, fuel gauge, etc.). SAE standard J1050, Appendix D (SAE, 2009)
provides a drafting procedure for determination of the boundary of the zone on the instrument clus-
ter plane, which will be visible to most drivers. It is the area on the cluster plane that will be visible
to at least one eye of all drivers whose sightlines from the left and right eyes are tangents to the 95th
percentile left and right eyellipses, respectively.
Thirty-Five-Degree Down-Angle Cone: The 35-degree down angle zone denes the lower
boundary for locating controls and displays such that the driver will not require eye movements
larger than 35 degrees down in the vertical (elevation) direction ...