A one-line range ('the load shall be carried between 0 and +4 °C') answers no question in a dispute, because it does not say where, how or by whom the temperature is measured. The clause defines five things: the range, the measuring point, the tolerance, the record owner and the consequence of a deviation.
| What is measured | When it governs |
|---|---|
| Air temperature | Continuous monitoring, alarm threshold |
| Product core temperature | Acceptance, rejection and compensation |
Air in the body and the core of the product do not change at the same rate. If the contract does not say which governs, the air temperature rising when a door opens counts as a breach even though the product stayed in range. Every door opening produces a deviation; unless the tolerance is defined by duration and frequency, all of them are technically breaches.
Who keeps the record decides who holds the evidence in a dispute, and both sides keeping their own is the sturdiest arrangement. For instruments, EU Regulation 37/2005 is a useful model: for quick-frozen food, air temperature is recorded at frequent intervals with instruments complying with EN 12830, EN 13485 and EN 13486, and the records are kept for at least one year.
