HSS Version History

HSS 2025 Release History

Release 8.4 (10/15/24)

  • Implements user-defined crash modification factors (CMFs)
  • Adds map-based segmentation for rural and urban facilities
  • Adds procedure for High-Speed Urban Intersections (NCHRP 17-68)
  • Adds procedure for Ramp Terminals at Single-Point Diamond Interchanges (NCHRP 17-68)
  • Adds procedure for Ramp Terminals at Tight Diamond Interchanges (NCHRP 17-68)
  • Computes and displays crashes as a ratio of vehicle miles traveled (VMT) in reports for segment analyses
  • Computes and displays crashes as a ratio of million entering vehicles in reports for intersection analyses
  • Adds diagrams for each Ramp Terminal type
  • Shows predicted PDO crashes for Multilane 3SG intersection
  • Fixes crash when opening Details page
  • Fixes crash when loading ramp segments
  • Fixes incorrect collision distribution calculations for One-Way, All-Way, and Six or More Lanes Urban sections
  • Triggers warning of incorrect sum of proportions when changing intersection type
  • Triggers warning when number of cross section lanes is 2 for rural ramp segment
  • Fixes HSS not converting HCS Highways “Area Type” input correctly
  • Includes other minor bug fixes and improvements

HSS 2024 Release History

  • Separates HSS from HCS suite
  • Upgrades the installation and software activation procedures with up-to-date protection
  • Adds procedure for Urban and Suburban Roadway Segments with Six or More Lanes
  • Adds procedure for Intersections of Urban and Suburban Arterials with Six or More Lanes
  • Adds procedure for Urban and Suburban One-Way Arterial Roadway Segments
  • Adds procedure for Intersections of Urban and Suburban One-Way Arterials
  • Adds procedure for Intersections with All-Way Stop Control
  • Adds procedure for Three-Leg Intersections with Signal Control on Rural Highways
  • Adds EB Analysis for Roundabouts
  • Improves EB Analysis for Rural Multilane
  • Adds example files for new procedures
  • Redesigns layout of ramp terminal input page
  • Adds approach directions for 4SG and 3SG intersections
  • Adds new pedestrian volume to compute pedestrian activity level
  • Adds new option of “None” for Left-Turn Phasing
  • Adds error message to show when number of left-turn phases are more than three for 3SG intersections
  • Improves crash distribution computation and related warning messages
  • Fixes some global parameters not applying to the section page for facility analyses
  • Adds option to allow hiding of economic reports
  • Adjusts min-max range for roundabout entry width based on number of entry lanes
  • Fixes entry width CMF for one circulating lane in Roundabouts
  • Fixes updating of segment length of speed change lane in Details page
  • Fixes incorrect predicted crash results for urban segments and urban intersections
  • Fixes CMF1 (Lane Width) for Rural Multilane Undivided Segment when AADT<400 or AADT>2000
  • Fixes CMF2 (Approaches with Left-Turn Lanes) and CMF3 (Approaches with Right-Turn Lanes) for Rural Multilane 4ST
  • Fixes CMF2 (Shoulder Width) calculation for Rural Two-Lane and Multilane Segments
  • Adds note to show CMFs are not applicable for signalized intersections of Multilane Highways
  • Fixes Full View refresh issues
  • Includes other minor bug fixes and improvements

Note: HSS2024 implements the first edition of the Highway Safety Manual, NCHRP Project 17-70, NCHRP Project 17-68, and NCHRP Project 17-58

HSS (Part of HCS) Release History

  • Allows opening of *.xuf files by converting HCS Freeways and Highways facilities to HSS facilities
  • Includes other minor bug fixes and improvements

  • Adds metric unit system support
  • Allows coding of ramp and freeway into one facility
  • Adds Full View support
  • Redesigns module icon, ‘About HCS’ window, and start page
  • Adds new graphs for freeway segments
  • Includes other minor bug fixes and improvements