Devices · Syringes & needles

About the Syringes & needles category

Devices › Syringes & needles syringe units dead volume needle gauge & length

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dr_okonkwoTL4 Moderator12 Jun 2026#1

Community wiki post. Any member at trust level 3 or above can edit this post; every edit is recorded. Last edited by mira.patel on 22 Jun 2026.

7 Jul 2026 — dr_okonkwo: Clarified the distinction that was causing repeat questions below.
22 Jun 2026 — mira.patel: Added the worked example and a unit label to the table header.

Editors: dr_okonkwo, mira.patel, hana.sato

Staff post. Actions described here are recorded in the public moderation log and may be challenged in Meta.

Insulin syringe graduations, dead volume, gauge and length selection, and reading units correctly.

This post is a community wiki: any member at trust level 3 or above can edit it, and every edit is recorded with its author and a note. If the scope described here has drifted from what actually gets posted, edit it rather than starting a topic about it.

What belongs here

Questions specific to syringes & needles, with the units and the context stated.
Reports and datasets, with the collection method stated.
Disagreement about the substance, conducted in public.

What belongs elsewhere

Anything urgent belongs in Safety, immediately, and not here.
Anything about how this site works belongs in Meta.
Requests for a maintained page belong in Wiki requests.

Before posting, it is worth checking the documentation commons and this category's tag pages. A great deal of what gets asked here has a maintained answer with a review date on it, which is more reliable than a two-year-old reply.

7 likes 2mo

owen.bradyTL4 Moderator14 Jun 2026#2

Staff post. Actions described here are recorded in the public moderation log and may be challenged in Meta.

Moderation notes for this category, so that nothing about how it is run is a surprise.

Topics get moved into and out of here regularly. A move is not a judgement — the category tree is not obvious from outside and putting a question in the wrong place is expected. When I move something I say so in the topic and the action appears in the public log with the guideline cited.

The two guidelines that come up most often in this category are R2, on supplying a source when asked, and R7, on category placement. Neither is used punitively.

0 likes 1mo

a.friskTL2 Moderator16 Jun 2026#3

As a member rather than staff: the most useful thing I did when I started reading this category was to work through the tag pages rather than the topic list. The topic list shows you what is recent. The tags show you what is settled.

32 likes 1mo

m.ibarraTL2 Moderator18 Jun 2026#4

Suggestion for the wiki post above: it would be worth linking the two or three most-referenced topics in this category directly, since new members reliably ask for exactly those. Happy to make the edit myself if nobody objects, with a revision note.

16 likes 1mo

c.boatengTL2 Moderator20 Jun 2026#5

Needle length: typical lengths for subcutaneous injection are 4-6 mm (short), 8 mm (standard), or 10-12 mm (longer). Longer needles are needed for deeper tissue or if you have abdominal adiposity.

6 likes 1mo

This topic was referenced in

Gauge and length selection for subcutaneous injectionDevices › Syringes & needles · 55 replies

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