Dear Wilma Sue
No, I'm sorry but any finish including the catalyzed water based coatings like Bona Kemi's Traffic won't protect a floor for long against a puddle of urine. Urine is mostly water, and water molecules are like little octopi and will slither past the smallest seam And then invite more of it's friends on the same route. The wood will swell and the acid in the urine will stain the wood an ugly smelly black color. And all the damage is under the finish at this point.
That all said, of all the finishes I have used, I find that the good old Oil Modified Poly has just about the best water repellancy of all the finishes. Thats because it is truly a crosslinking finish, and the molecules in the finish form a flexible but impermeable bond on the wood. It may not be as scuff resistant as the Traffic but poly ages better, to a mellow amber tone.
I have seen water based finishes that in only a few years become so opaque that you could hardly tell the wood species under the finish. They also may tend to get a bit brittle in harsh sunlight. But check out jobs that are 5-10 years old with the Bona Kemi Traffic and see for yourself.
Any contractor who is recommending any finish should have and be willing to show you jobs that are at least that old. This is the only way you can really assess the finish and the floor contractor. Oh, and the Hiring contractors is a worthwhile read in the Hardwood Authority section of this site.
As always your Most humble servant, Joseph, the Wood Floor Doctor.