Intersection Sight Distance Calculator
Actual approach-speed exposure against independent maneuver gap criteria and surveyed available sight, not passing maneuver model or sight clearance. Caller independently establishes units, regime, calibration and applicability; this does not establish design-code compliance, authenticity, operational safety, treatment efficacy or a validated forecast.
Description
A sight-distance screen compares available distance with speed times an accepted time gap.
A sight-distance screen compares available distance with speed times an accepted time gap.1
The gap and measurement conditions require independent selection for the intersection movement. Use this tool to calculate intersection Sight Distance from the supplied measurements and assumptions.
When to use Intersection Sight Distance Calculator
Use this tool to calculate intersection Sight Distance from the supplied measurements and assumptions. Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
How to use Intersection Sight Distance Calculator and understand its results
- Establish the SI units or caller unit basis, load signs, measurement interval, model conditions and independently chosen coefficients or references.
- Enter observedIntersectionApproachSpeedsMSecond, callerVerifiedGapAcceptanceSeconds, observedAvailableSightDistancesM, using the field meanings and rules below, then run the tool.
- Read callerGapSightDemandsM, signedObservedSightMarginsM. Interpret the fields using their units, signs and evidence conventions below.
- If input validation fails, correct the reported field and run again. Before applying the result, check reference scope, model assumptions and any missing evidence or placeholder values.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedIntersectionApproachSpeedsMSecond | Observed intersection approach speeds m second | list of number | Required |
| callerVerifiedGapAcceptanceSeconds | Caller verified gap acceptance seconds; caller assertion or measurement requiring independent evidence | list of number | Required |
| observedAvailableSightDistancesM | Observed available sight distances m | list of number | Required |
Enter nonempty aligned nonnegative approach speeds in m/s, positive independently accepted gaps in seconds and nonnegative available distances in m. Demand is speed×gap; reserve is available−demand. No gap choice, obstructions, maneuver geometry or standard compliance is determined.
demandM_i=speedM/s_i×gapSeconds_i; reserveM_i=availableM_i−demandM_i Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| callerGapSightDemandsM | Caller Gap Sight Demands M; follow the units, sign, ordering and evidence convention stated above | list of number |
| signedObservedSightMarginsM | Signed Observed Sight Margins M; follow the units, sign, ordering and evidence convention stated above | list of number |
{
"input": {
"observedIntersectionApproachSpeedsMSecond": [
10,
20
],
"callerVerifiedGapAcceptanceSeconds": [
5,
6
],
"observedAvailableSightDistancesM": [
60,
100
]
},
"output": {
"callerGapSightDemandsM": [
50,
120
],
"signedObservedSightMarginsM": [
10,
-20
]
}
}Limitations and assumptions
The gap and measurement conditions require independent selection for the intersection movement. Interpretation depends on the units, sampling scope and exact model described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse evidence arrays fail validation; the specific bounds and alignment requirements are stated above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful result reporting false, no matches or missing evidence.
Alternative or Complementary methods
Use Passing Sight Distance Calculator for this related task: A passing-distance screen combines opposing and passing speeds over a maneuver time.
Use Roundabout Capacity Calculator when its separate inputs and assumptions fit the question: A gap-acceptance roundabout model relates conflicting flow to critical and follow-up gaps.
References
-
Intersection Sight Distance Calculator — tool.io
Similar or alternative tools
- Passing Sight Distance Calculator
A passing-distance screen combines opposing and passing speeds over a maneuver time.
- Roundabout Capacity Calculator
A gap-acceptance roundabout model relates conflicting flow to critical and follow-up gaps.