Source: https://guthlabs.ai/docs/instruments/beaufort-wind-scale-lookup/implementation/

instrument implementation / implementation-contract

# Beaufort Wind Scale Lookup implementation

A source-bound implementation contract for Beaufort Wind Scale Lookup; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t7-064

**Effect**: Computation or source lookup only

## Input and validation requirements

The specification says wind speed may use any unit but does not define mandatory unit metadata, parsing, or behavior for extreme out-of-range values. A bare value of 10 can therefore yield B5 when read as m/s or B3 when read as mph, and an extreme finite input can overflow during conversion unless saturation or rejection is implemented.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "wind_speed": 0,
    "unit": "m/s",
    "measurement": "10-minute mean at 10 m"
  },
  "expected_outputs": {
    "beaufort_number": 0,
    "land_description": "Calm; smoke rises vertically.",
    "sea_description": "Sea like a mirror."
  },
  "reference_data": {
    "beaufort_rows": [
      {
        "force": 0,
        "wind_speed_m_s": "0.0-0.2",
        "land_description": "Calm; smoke rises vertically.",
        "sea_description": "Sea like a mirror."
      }
    ],
    "source_convention": "WMO Beaufort scale, widely tabulated standard value"
  },
  "working": "Input is already in m/s: 0 m/s. The value is in the force-0 row, 0.0-0.2 m/s. Therefore Beaufort force = 0. The relation also gives v = 0.836·0^1.5 = 0 m/s, but the table determines the category."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/beaufort-wind-scale-lookup/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/beaufort-wind-scale-lookup/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/beaufort-wind-scale-lookup/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche7/tranche7-results.json`
