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Development of a Posted Speed Limit Setting Procedure and Tool (2021) / Chapter Skim
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Pages 171-174

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From page 171...
... NCHRP Web-Only Document 291: Development of a Posted Speed Limit Setting Procedure and Tool 159 ABBREVIATIONS Abbreviation Term 4U Four-lane undivided 5T Four lanes and a TWLTL AADT Annual average daily traffic (veh/d) AADTR AADT estimate from FHWA HPMS or SEMCOG system-wide data rounded to nearest 10 AASHTO American Association of State Highway and Transportation Officials Abs(PSL−Avg)
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From page 172...
... NCHRP Web-Only Document 291: Development of a Posted Speed Limit Setting Procedure and Tool 160 Abbreviation Term HPMS Highway Performance Monitoring System HSIS Highway Safety Information System HSM Highway Safety Manual Int_Type1 Description of End Point #1: signal, all-way stop, stop, roundabout, or other break point Int_Type2 Description of End Point #2: signal, all-way stop, stop, roundabout, or other break point ISW Inside shoulder width (ft) K Constant associated with the confidence level (1.645 for 95% confidence)
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From page 173...
... NCHRP Web-Only Document 291: Development of a Posted Speed Limit Setting Procedure and Tool 161 Abbreviation Term Pace_LV Lower speed value of 10-mph pace for the site Pace_Per Percent of vehicles in 10-mph pace for the site Pace_UV Upper speed value of 10-mph pace for the site PDO Property damage only PedAuto Typical or average distance between the sidewalk and the automobile lane for the segment, sum of the following (when present) : parking width, bike width, bike-auto separation, and sidewalk to road separation (ft)
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From page 174...
... NCHRP Web-Only Document 291: Development of a Posted Speed Limit Setting Procedure and Tool 162 Abbreviation Term SLSG Speed Limit Setting Group SLS-Procedure Speed Limit Setting Procedure SLS-Tool Speed Limit Setting Tool Spd85 85th percentile speed (mph) SpdAve Average speed for the site (mph)
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