B Why Does a New Syringe Have an Open Piston?

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The piston in a new syringe is often not completely closed to prevent adhesion to the front wall, which can occur due to the seal created by the rubber against the plastic. This design may also help differentiate new syringes from used ones. Some users report that leaving syringes partly open helps avoid sticking issues, which can happen even with new syringes. There is variability in syringe designs, with some being fully closed and others not. Overall, the design choice appears to balance functionality and usability in different applications.
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Why the piston in a new syringe is not completely closed,,?
Is it just because of to differentiate from New one or it just have a scientific reason
 
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I am just guessing, but it may be to prevent adhesion to the front wall.
 
Dale said:
I am just guessing, but it may be to prevent adhesion to the front wall.
May be,, because even after not completely closed it well tight..
 
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Leodoc said:
Why the piston in a new syringe is not completely closed,,?

Are you sure that this is always the case?
 
Leodoc said:
Why the piston in a new syringe is not completely closed,,?
Is it just because of to differentiate from New one or it just have a scientific reason
Welcome to the PF.

Can you say more about your question? Using Google Images or Google Shopping, I see new syringes that are fully closed and some that are open a little.

https://cdn-1.au.xmsymphony.com/4d9c396d11102d97ff4226a2e42b15a4/contents/V00064/insulin-syringe.jpg

insulin-syringe.jpg
 

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I leave syringes partly open because they sometimes stick. I don't know if this would happen with new ones, or whether it is due to slight contamination remaining after use. (Despite washing.)
My reason, based on experience of not doing it, is that I can press hard and break the seal/bond, but if I pull the rubber gets pulled off the plastic plunger.

Just in case PC PF people are worried, I do not use these for medicines nor anything like that! Mainly inks and aqueous solutions for photographic processes.
 
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