Culture Media / Buffer Recipe Scaler implementation

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

t5-169

Effect

Computation or source lookup only

Input and validation requirements

A zero recipe volume produces undefined scaling and should be rejected. The specification also leaves unit normalization unspecified, allowing a severe error: 5 g is correct for 1 L to 500 mL, whereas raw numeric division would produce 5000 g.

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": {
    "recipe_amounts": {
      "NaCl_g": 10,
      "glucose_g": 5,
      "water_mL": 1000
    },
    "recipe_volume_L": 1,
    "target_volume_L": 2.5
  },
  "expected_outputs": {
    "scaled_amounts": {
      "NaCl_g": 25,
      "glucose_g": 12.5,
      "water_mL": 2500
    }
  },
  "working": "Scale factor = target_volume / recipe_volume = 2.5 L / 1 L = 2.5. NaCl = 10 g × 2.5 = 25 g. Glucose = 5 g × 2.5 = 12.5 g. Water = 1000 mL × 2.5 = 2500 mL."
}

Other records

Sources and evidence

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

• VERIFIED_LEDGER.json
• evidence-tranche5/tranche5-results.json