Culture Media / Buffer Recipe Scaler mechanism

Model scope

The exact ambiguity requiring review is that the specification does not state volume units or require recipe_volume and target_volume to be dimensionally compatible. The honest label is appropriate: this is an arithmetic scaling aid and should not be presented as recipe validation or medical advice.

• The formula is correct for linear scaling when recipe_volume and target_volume use the same units and recipe amounts are specified for the recipe's final volume.
• The specification does not define constraints for negative amounts or volumes, nor whether target_volume=0 is permitted.
• The formula does not account for non-linear preparation effects, stock-solution concentrations, density changes, evaporation, or practical rounding; it is only a proportional arithmetic scaler.

Units and conventions

• recipe_volume and target_volume must use identical units, or one must be explicitly converted before calculating the ratio.
• Each recipe component amount is scaled independently and retains its original unit, such as grams, milligrams, milliliters, or moles.
• The recipe amount represents the quantity required in the stated recipe final volume.
• For a final-volume recipe, component quantities are assumed to scale linearly with volume.

Inspectable vector

One of 4 source-bound review vectors:

{
  "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."
}

Failure boundary

BREAK_CLAIMED · SELF_FLAGGED

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.

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
• BOUNDARY_HAZARD_CATALOG.json