What we have written on the cold chain134 / 154

Dry ice is never kept in an airtight container: the subliming gas builds pressure. Below: how to choose the container and the place, the OSHA and NIOSH limits, and a worked calculation of why gas in a closed room is a risk.

Compare ownership, pooling and mixed models at equal volume and period. Check contract terms for washing, returns, loss and peak capacity.

Plan quay staging, handoff aboard and return loading. Link product readings, equipment status and responsible staff in the trip log.

Dry ice is made by expanding liquid carbon dioxide into snow and pressing it. Because it sublimes, compare suppliers on the net kilos weighed at delivery, not on price per kilo.

Being recyclable and being recycled are not the same thing. In 2023 only two EU countries met the 2030 plastic packaging target; the collection route decides where a box ends up.

Plan vehicle access, stock location and post-event returns in one flow. At each handoff, record time, product, record owner and next action.

Dry ice is -78.5 °C at normal pressure and turns straight into gas without melting, so it needs a barrier from the product and a vented container.

Split the day's stock into a working volume and a closed reserve, keep the reserve in a pre-chilled insulated container, and tie every reading to the food.

Check an ATP certificate on three points: the vehicle's identity, its class and the month and year it is valid until. Validity runs 6 years from manufacture and a passed inspection adds 3.

Do not blame the compressor alone. Compare kWh use with door, product-in and defrost records.

The food arrives early and the bell rings late; the wait in between happens at school. A three-time record documents the waiting pot, and a retained sample of every dish is kept for 72 hours.

What WHO's constant-temperature test, the ISTA 7E profiles and ASTM D3103 each measure, and how to work out degree-hours for your own route.