normally, the needle of a 5ml syringe is No.7, the needle tube is 3cm long, and there is also a No.5 needle, and the needle tube is 3.8cm long.
generally, 2ml, 5ml, 1ml or 2ml syringes are used, occasionally 5ml or 1ml syringes are used, and 1ml syringes are used for intradermal injection. The syringe barrel can be made of plastic or glass.
and usually there is a scale indicating the volume of liquid in the syringe. Glass syringes can be sterilized by autoclave, but the processing cost of plastic syringes is low.
Extended information:
Syringes can also be used to inject medical equipment and containers, such as scientific instruments in some chromatography, through rubber diaphragms. Injecting gas into blood vessels will cause air embolism.
the way to remove air from the syringe to avoid embolism is to turn the syringe upside down, tap it gently, and then squeeze out a little liquid before injecting it into the blood stream.
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