Chemo running through Luer Lock C35

Can anyone please explain why is necessary to use the adapter Luer Lock ( C35) in between the chemo line (set up as a secondary) and the primary line?

What advantages this provides? Is this a standard of practice?

Recently I started working on an oncology floor, and I just had my first chemo spill. I think was because the chemo line (secondary line) was not tighten strongly enough to this Luer Lock adapter. I simply don't see the sense of this adapter.

Thank you

I believe Texium are a standard of practice vs c35. I have only been to 2 facilities and I am currently at stanford. Both of us utilize it.

http://www.carefusion.com/assets/images/our-products/infusion/body-components/chemo-safety-system_detail_IF_0812-0009-1.png

Thank you so much for your answer. Why is this adaptor used anyway?

Thank you so much for your answer. Why is this adaptor used anyway?

looks like it was designed for chemo specifically.

http://www.carefusion.com/documents/brochures/infusion/IF_Chemo-Safety-System_BR_EN.pdf