Devices · Cold chain · continued

Temperature loggers worth the money — the long version posts 121–128

Devices › Cold chain storage freeze-thaw temperature excursion Closed

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

sharps_binTL2Regular27 Jan 2026#121

Where I part company with post #117, and it is a narrow parting.

Travel with medication: carrying a vial across borders requires planning if temperatures will exceed the range or if journey time is long. Insulated travel cases with ice packs are common solutions.

0 likes 6mo

i.boatengTL228 Jan 2026 · edited#122

Assessing an excursion: if a package sat at room temperature for a time, visual inspection (cloudiness, discoloration, particles) can alert you to problems. Not visible does not mean not damaged, but visible problems are a reason to contact the supplier.

0 likes 6mo

outline_firstTL3Wiki editor30 Jan 2026#123

e.mbeki, post #102: This follows post #99 rather than contradicting it. I have three months of notes on Temperature loggers worth the money and the honest summary is that the trend is real and the week-to-week numbers are noise. I nearly drew the opposite conclusion from the first fortnight. Go to post

Good question, well framed, and I would like to see it answered properly.

18 likes in reply to #102 6mo

se.okaforTL231 Jan 2026#124

The arithmetic in post #121 is right; the assumption feeding it is the part to check.

The honest summary: pack quality is visible, transit history is not, and only the second determines what happened to the material.

Not a strong opinion, just a consistent one.

8 likes 6mo

cannula_traceTL3Regular2 Feb 2026#125

Post #121 put the caveat in the right place and I want to underline it.

A phase-change pack holds a defined temperature while it changes state and then behaves like anything else. A gel pack starts cold and warms continuously. They are different tools for different transit lengths.

This is where my knowledge stops and I would rather mark the edge than blur it.

0 likes 6mo

j.restrepoTL23 Feb 2026#126

Collapsed as off-topic by two members at trust level 3 or above

Building on post #125 rather than restating it.

Temperature loggers worth the money is one of those subjects where the general answer and the answer for a specific case diverge, and the thread will go in circles until someone says which one is being asked for.

c.wijnbergTL2Member5 Feb 2026#127

KAndersson, post #118: Domestic refrigeration: most lyophilised peptides are stored at 2–8 °C (35–46 °F). That is standard refrigerator temperature. Check your refrigerator's actual temperature; some are warmer than the label. Worth saying I have only my own numbers here, and n is small. Go to post

For anyone finding this later: the short answer on Temperature loggers worth the money is that it depends on one thing, and the rest of the thread is people identifying which thing.

13 likes in reply to #118 6mo

da.bakkerTL26 Feb 2026#128

Knowlton, post #91: I would be cautious about generalising from the Temperature loggers worth the money example above. It is a good example. It is one example. Go to post

Insulation performance depends on the mass of the coolant more than on the thickness of the box. A large pack in a modest box outperforms a small pack in a good one.

The short answer was in the first line; everything after is the working.

4 likes in reply to #91 6mo

This topic was referenced in

Domestic fridge temperature mapping: a cheap experimentDevices › Cold chain · 2 replies
A fridge failure and how I assessed the contents afterwardsDevices › Cold chain · 18 replies

This topic was closed 30 days after the last reply. Closing is automatic for quiet topics so that a settled answer does not collect new questions underneath it. If you have a follow-up, open a new topic and link back to this one — that keeps both readable and gives your question its own title.

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