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My lab conditions today were within an acceptable range 19°C/1atm, no correction for the slight change in density of water was applied. My syringe wasn't an exact match but it'll do, I only had one of these syringes available so I grabbed 2 childrens acetaminophen syringes with 1.25 ml to 5 ml in 1.25 ml increments. I filled and cleared the syringe several times making sure no bubbles were present in the nipple and no water was protruding from the nipple (I also made sure to dry the outside after each fill). The baseline for my measurements included the dead volume.

To start I determined my own precision in drawing up into the syringe and extruding the water out was 1% (n=6). This demonstrated that I could reproducibly use a syringe to draw up a specific amount. From here I determined the volume delivered at the low and high points of the (rather thick) volume markings (using the line produced by the plunger seal at the surface of the liquid as my mark for volume drawn up). I chose this route of measuring because it includes the entire range of possible measurements a person can make.

The syringes are both accurate in their deliveries (98.5 +/- 1.9% for Advil, 97.4 +/- 1.1% acetaminophen), however the infant Advil could definitely tighten up on their ranges.

As a disclaimer my daughter is 4.5 years old so these syringes have seen some use, gone through the dishwasher and sat for at least a year unused, I'm really surprised I couldn't find more since she had ear infections and her tonsils removed.

Anyway this has been my ted talk.