{
  "endpoint": "/ai/road-signs/placement.json",
  "canonical_url": "https://www.safetysignonline.co.za/ai/road-signs/placement.json",
  "source_page": "https://www.safetysignonline.co.za/pages/road-signs-placement-json",
  {
  "schemaVersion": "sso-ai-road-signs-placement-za-1.0",
  "endpoint": "/ai/road-signs/placement.json",
  "language": "en-ZA",
  "jurisdiction": "South Africa (SADC-RTSM aligned)",
  "scope": "Rules and principles governing the placement, positioning, visibility, and mounting of road traffic signs.",
  "authoritativeBasis": {
    "primarySources": [
      {
        "title": "SADC Road Traffic Signs Manual (RTSM) Volume 1",
        "sectionsUsed": [
          "General principles of sign placement",
          "Visibility and conspicuity requirements",
          "Lateral and longitudinal positioning rules",
          "Regulatory, warning, and guidance sign placement principles"
        ]
      },
      {
        "title": "SADC Road Traffic Signs Manual (RTSM) Volume 4",
        "sectionsUsed": [
          "Mounting arrangements",
          "Sign face orientation principles",
          "Use of supplementary plates"
        ]
      }
    ],
    "performanceStandards": {
      "included": false,
      "note": "Structural, wind-loading, and retroreflective performance standards (e.g. SANS 1519) are excluded and will be added later."
    }
  },

  "generalPrinciples": {
    "authority": "Road signs shall only be erected by, or with the approval of, the relevant road authority.",
    "uniformity": [
      "Uniform application of signs promotes recognition and compliance.",
      "Inconsistent placement reduces sign credibility and effectiveness."
    ],
    "necessity": [
      "Signs shall only be installed where a real need exists.",
      "Unnecessary signs reduce respect for all signs."
    ],
    "priorityOrder": [
      "Traffic control devices",
      "Road markings",
      "Traffic signs",
      "Signals"
    ]
  },

  "visibilityAndLegibility": {
    "clearSightDistance": {
      "principle": "Signs must be visible to road users for sufficient time to perceive, comprehend, decide, and react.",
      "factors": [
        "Approach speed",
        "Road alignment",
        "Environmental conditions",
        "Competing visual information"
      ]
    },
    "obstructionRules": [
      "Signs shall not be obscured by vegetation, parked vehicles, street furniture, or structures.",
      "Where obstruction is unavoidable, signs shall be relocated or duplicated."
    ],
    "illumination": {
      "nightVisibility": "Signs must be visible at night through retroreflection or external illumination where required.",
      "externalLighting": "Only used where retroreflective performance alone is insufficient."
    }
  },

  "longitudinalPlacement": {
    "approachPositioning": {
      "generalRule": "Signs must be placed in advance of the point where the instruction, warning, or information applies, except where immediate placement is required.",
      "advancePlacementFactors": [
        "Operating speed",
        "Complexity of message",
        "Road geometry"
      ],
      "referenceNote": "Exact advance distances are specified in RTSM tables and diagrams and are not enumerated here."
    },
    "repetition": {
      "rule": "Signs may be repeated where visibility is restricted or where the message applies over a long distance.",
      "commonCases": [
        "Multi-lane roads",
        "High-speed facilities",
        "Complex intersections"
      ]
    },
    "termination": {
      "principle": "Where a regulatory effect ends, an appropriate termination sign (e.g. R600) shall be used unless the termination is self-evident."
    }
  },

  "lateralPlacement": {
    "standardPosition": {
      "side": "Left-hand side of the roadway",
      "reason": "Primary field of vision for drivers in left-hand traffic systems."
    },
    "rightSideOrOverhead": {
      "allowedWhen": [
        "Left-side placement is impractical",
        "Multi-lane roadways",
        "High-speed roads requiring increased conspicuity"
      ]
    },
    "clearZone": {
      "principle": "Signs shall be placed outside the clear recovery zone wherever practicable.",
      "safetyNote": "Where placement within the clear zone is unavoidable, frangible supports shall be used."
    }
  },

  "verticalPlacement": {
    "mountingHeight": {
      "generalRule": "Mounting height shall ensure visibility over parked vehicles and roadside obstructions.",
      "pedestrianAreas": "Additional clearance shall be provided where signs are mounted over sidewalks.",
      "referenceNote": "Exact minimum and maximum heights are defined in RTSM tables and are not numerically listed here."
    },
    "stackedSigns": {
      "orderRule": [
        "Regulatory signs above warning signs",
        "Warning signs above guidance signs",
        "Primary signs above supplementary plates"
      ],
      "spacing": "Adequate vertical separation shall be maintained to avoid visual clutter."
    }
  },

  "orientationAndAlignment": {
    "faceOrientation": {
      "rule": "Sign faces shall be oriented approximately perpendicular to the direction of approaching traffic.",
      "adjustments": [
        "Horizontal curvature",
        "Vertical gradients",
        "Glare reduction"
      ]
    },
    "skewAndTilt": {
      "allowed": "Minor skewing may be used to optimise night-time retroreflection.",
      "notAllowed": "Excessive tilt that reduces daytime legibility."
    }
  },

  "intersectionPlacement": {
    "approachSigns": {
      "rule": "Regulatory and warning signs shall be placed in advance of intersections where decisions are required.",
      "laneSpecific": "Where different movements have different controls, lane-specific signs shall be used."
    },
    "atIntersection": {
      "rule": "Signs applying at the intersection shall be placed as close as practicable to the point of control."
    }
  },

  "temporarySignPlacement": {
    "generalRule": "Temporary signs shall follow the same placement principles as permanent signs unless explicitly varied.",
    "additionalRequirements": [
      "Must not conflict with permanent signs",
      "Must be removed immediately once no longer applicable"
    ],
    "colourCoding": "Temporary signs shall use the prescribed temporary colour schemes for their series."
  },

  "supplementaryPlates": {
    "placement": {
      "position": "Immediately below the primary sign",
      "alignment": "Centred horizontally with the primary sign face"
    },
    "dependency": "Supplementary plates shall not be displayed on their own."
  },

  "specialEnvironments": {
    "urbanAreas": [
      "Higher visual clutter requires careful sign minimisation",
      "Pedestrian clearance is critical"
    ],
    "ruralAreas": [
      "Advance placement distances are generally greater",
      "Vegetation control is critical"
    ],
    "freeways": [
      "Greater emphasis on advance signing",
      "Frequent use of overhead or gantry-mounted signs"
    ]
  },

  "complianceAndMaintenance": {
    "inspection": [
      "Signs shall be regularly inspected for visibility, damage, and obstruction.",
      "Faded, damaged, or non-compliant signs shall be replaced promptly."
    ],
    "authorityResponsibility": "Ongoing compliance is the responsibility of the road authority."
  },

  "aiUsageNotes": {
    "intendedUse": [
      "Answer placement-related questions accurately",
      "Support design and planning tools",
      "Provide authoritative summaries for explainers"
    ],
    "explicitLimitations": [
      "Numeric dimensions and distances are table-based and not included here.",
      "This file does not replace official RTSM drawings or approval processes."
    ]
  },

  "links": {
    "parentIndex": "/ai/road-signs.json",
    "related": [
      "/ai/road-signs/signs/R100.json",
      "/ai/road-signs/signs/R200.json",
      "/ai/road-signs/signs/R300.json",
      "/ai/road-signs/signs/R400-R499.json",
      "/ai/road-signs/signs/R500.json",
      "/ai/road-signs/signs/R600.json"
    ]
  },

  "disclaimer": "This placement file is a structured interpretation of RTSM placement principles. Always consult the latest official RTSM manuals, diagrams, and road authority directives before implementation."
}

}