Anti Siphon

[Jim Robinson]

Is this hydrant style of outside hose connection considered to be of the anti siphon type? I know they self drain below frost line, but I don't know about the anti siphon aspect.

[A.D. Miller]

Is this hydrant style of outside hose connection considered to be of the anti siphon type? I know they self drain below frost line, but I don't know about the anti siphon aspect.

JR: This appears to be what you have:

Simmons Manufacturing (http://www.simmonsmfg.com/specifications/hydrant_lengths.html)

It is not of the anti-siphon type, but could be with the simple addition of an anti-siphon collar (http://www.thehardwarecity.com/products/69750-Hose-Bib-Anti-siph-Valve/2836112). There is not enough detail in the photo to tell if one is installed.

[Jim Luttrall]

I really like these for outdoor use but have often questioned their use due to contamination issues. Seems like it would need some sort of double check valve similar to irrigation systems.