If you are plumbing the drain for the RO directly to a waste line then yes you need an air gap. If the RO can be drained to a laundry tub there just needs to be a 1" gap between the drain line and flood rim of laundry tub.
RJ

Thx RJ. Not sure what you mean by a "waste line." Obviously I know nothing about plumbing. I am having this installed professionally, but wanted the views of the good folks on this forum before I hear what my plumber suggests. This will be installed in a seperate coffee station area in my new kitchen. There will also be a small bar sink there with a drain. So no possibility of a laundry tub. I think I'm hearing you say I need an air gap faucet and that I need to return the one I bought.

yes, air gap one.

Thx guys. Just found out I can order an Airgap add-on for my faucet, so I've done so. Should all be good now. BTW, is this "Air Gap" stuff common knowledge among reputable plumbers and will they know how to install this thing?

Make sure what you ordered is an AIR GAP and not a check valve. They are not the same.

You would be better off with an air gap faucet.

Air gap faucets prevent cross-contamination. Air gaps are code required when connecting a potable water appliance to a drain.

Thx justalurker. The website description of the product said "Air Gap" so I hope that's what it is. Now just need to hope my plumber (chosen by my GC) knows about this stuff.

Is this a Master plumber, or is this someone who acts as a plumber when people are willing to pay him to act as a plumber?

One way to find out is to ask him if he can design DWV plumbing.

No, this would be a professional licensed plumber used by our very reputable and high-end (read pricey) GC. I haven't met them yet, but they will be around next week or so for istall, so just wondering about how common this knowledge and type of installation would be.

the answer is inside my question. A Master Plumber will know, and a whole lot more than I know. Nothing wrong with your asking him any question.

Perfect. Thx again for your help. If he doesn't know, i'll refer him to this forum!