Devices · Syringes & needles

Reading U-100 graduations, with a conversion table — what changed since

Devices › Syringes & needles worked example dead volume syringe units subcutaneous injection

m.brobergTL225 Jul 2025#1

Reading U-100 graduations, with a conversion table — what changed since Writing it up because I had to work it out twice and would rather nobody else did.

What changes if the standard account of Reading U-100 graduations is wrong? I ask because I have been treating it as settled and I noticed this week that I could not say why.

Working through the consequences rather than the evidence, since others here are better placed on the evidence.

1 like 12mo

p.ostergaardTL216 Jan 2026#2

If your calculated volume is under two graduations, choose a lower concentration rather than trying to read between marks. Precision comes from the preparation, not the eye.

That is my reading. Someone else read the same page differently and was reasonable.

0 likes 6mo

c.okaforTL3Regular23 May 2026#3

Reading the barrel at eye level matters more than any equipment choice. Parallax at a shallow angle is enough to shift a reading by a graduation.

13 likes 2mo

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Filter needles: when they help and what they cost youDevices › Syringes & needles · 50 replies

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