Cold chain: difference between revisions
Diff·revision 43 → 44·22:50, 12 Feb 2025
Difference between revision 43 and revision 44 of Cold chain. 2 lines changed; the page grew by 506 bytes.
| Revision 43 — 10:25, 3 Feb 2025 MarginNoteMars (talk) attribute range as a review estimate per talk 17,977 bytes ±0 | Revision 44 — 22:50, 12 Feb 2025 CostPerMgCory (talk) add citation 18,483 bytes +506 | ||
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| 101 | The mean kinetic temperature is 24.1 °C, some 8 °C above the arithmetic mean and only 6 °C below the maximum. Half the time at 2 °C bought almost nothing, because at that temperature almost no degradation occurred and the statistic weights by degradation, not by clock time.{{r|haynes1971}} | 101 | The mean kinetic temperature is 24.1 °C, some 8 °C above the arithmetic mean and only 6 °C below the maximum. Half the time at 2 °C bought almost nothing, because at that temperature almost no degradation occurred and the statistic weights by degradation, not by clock time.{{r|haynes1971}} |
| 102 | 102 | ||
| + | 103 | Three cautions attach to the statistic and are stated in the compendial guidance itself. It presumes a single Arrhenius-behaved degradation pathway with the assumed activation energy; where the real activation energy differs materially, the calculated value misrepresents the exposure. It is meaningless for freezing damage, which is not an Arrhenius process. And it is a summary, so it cannot substitute for the profile when the question is whether a specific threshold was crossed.{{r|usp1079,ich_q1a}} | |
| + | 104 | ||
| 103 | == Packaging and qualification == | 105 | == Packaging and qualification == |
| 104 | Between controlled environments, the product travels inside a package that must maintain its internal temperature without external power. The performance of such a passive shipper is a designed property, qualified against defined ambient profiles, and it is specific to a payload. | 106 | Between controlled environments, the product travels inside a package that must maintain its internal temperature without external power. The performance of such a passive shipper is a designed property, qualified against defined ambient profiles, and it is specific to a payload. |