Patrick, do you think that the state really didn't have any data on the efficacy of cable barrier systems? You seem to think that since the state did not conduct the research that no research has ever happened. I don't know of any, but I would be highly doubtful that ODOT or any conscientious highway builder would install a safety system that was untested.

I'm sure there is a great deal of data available on the efficacy of the cable barrier systems in the form of studies and real-world results. Such tests, on the states part would be unnecessary, of questionable worth, and probably extremely expensive.

I'm not sure that millions of dollars spent on concrete barriers is worth the remote possibility of one life saved every twenty or so years. There's also no indication at all that concrete barriers would have stopped this particular semi which seems to be assumed in this thread. The Broadway Extension is a fairly similar to Hefner Expressway in that truck traffic is very light -- probably lighter than Hefner since Hefner Expressway is also a state highway which is probably the best route to Enid from OKC.

We can't make the roads 100% safe, that's an unreasonable expectation. The best that can be done is that our highway builders allocate their resources in a manner to ensure that it will do the best for the most people.

Concrete barriers are much more expensive than the wire types. Therefore, I'd wager that say 200 miles of wire barriers will save more lives than 50 miles of concrete (or whatever the actual cost difference is). With unlimited money, I'd say install concrete barriers everywhere. Absent that, however, I'd say that road builders should try to protect as many people as possible using their limited resources.