How to Determine Length of Hypodermic Needle

Hypodermic needles are commonly used in tandem with syringes for injecting or extracting medications for patient health care. There are two health care industry-acceptable standards for measuring the length of hypodermic needles: by the "overall length" or the needle's "free length." The needle length is typically measured in inches or millimeters.

Things You'll Need

• Hypodermic needle
• Ruler (in inches/millimeters)

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Instructions

• 1

  Expose the hypodermic needle, using caution with the beveled tip.

• 2

  Measure with a ruler (with marked inches and millimeters) from the beveled tip of the needle, down the shaft to the opposite end.

  To get the overall length measurement, measure the length from the tip of the needle to the opposite end of the shaft. If the entire needle is not visible, the hypodermic needle can be measured by it's "free length," or the length of the needle shaft from the tip to the hub. The hub is typically made of plastic, but can also be metal, and has the end of the needle embedded in it to attach to a syringe.

• 3

  Note the length, identifying the type of measurement as "OAL" for overall length, or "FL" for free length.

• 4

  Dispose or store the needle appropriately. If the needle is used, use extreme caution and place the needle in a proper sharps container. See the resources section for more information about needle disposal on the Environmental Protection Agency's website.