Delta RetroSign GRX-1 User Manual page 33

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From the drop-down menu, select the relevant sign category:
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Now a list of signs for the chosen sign category appears. Click on the relevant sign to be
inspected or type text to filter the list:
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On the next screen, choose the correct variables for the sign you are about to inspect, e.g.
background color. Press the drop-down arrow next to the variable for a list of options (see
example below). Select sheeting type according to ASTM D4956-11A.
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The pass/fail threshold values for background, legend, and contrast are automatically
calculated (as in the example below) according to MUTCD requirements (see 'MUTCD library'
RetroSign GRX User Manual / December 2017
33
DELTA