The specifications and models of syringes and needles are as follows:
Subcutaneous injection 1ml 4.5~5, intramuscular injection 2.5ml 5.5~6, intravenous pulse injection, intravenous blood sampling 2.5ml 10ml 6.5~7,
Note: The thickness of the needle is indicated by several numbers, generally there are 4.5, 5, 6, 7, etc., 7 is the diameter of the needle is 0.7 mm (may be the outer diameter) generally children use 4.5 or 5, adults use 7.
The needle is a hollow metal needle that can be freely loaded and unloaded at the end of the syringe head, for safety and hygiene, disposable needles should be discarded after use and should not be reused.
Syringe barrels can be made of plastic or glass, and usually have a scale indication indicating the volume of liquid in the syringe.
Glass syringes can be sterilized with autoclaves, but because plastic syringes are less expensive to handle, most modern medical syringes are made of plastic, which further reduces the risk of bloodborne diseases.
Among drug users who inject intravenous drugs, the spread of the disease, especially HIV and hepatitis, is associated with the reuse of needles and syringes.