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The preferred option would be to consider a crashworthy system or at least mitigate against critical concerns, such as significant vehicle snag, launching/override, rollover, etc. In the end, it may be low enough of risk to have some leeway if posted speed or speed advisory sign denotes 25 mph or less. In the past we have been willing to give some on the urban roadside tree issue if posted speeds were 25 mph or less.

Thus, it might be feasible to post a speed advisory before bridge of 25 mph maximum. This discussion only pertains to inside separator rail.

I wondered if you were comfortable with also using the concrete end section shown in the photo below. It appears that the end section is only approximately 6’ long which is much shorter than our standard IDOT concrete barrier tapered end section (which is 16’ long - see attached). We are in the process of concepting a bridge replacement that has 4 adjacent entrances and using the tapered end section detail will result in having to relocate some of these entrances.  

I appreciate your help!

With regards to the end section, the response is largely the same. A crashworthy end section like the one shown in the attachment is preferred. However, if the speed is the area are kept below 25 mph, then concerns with vehicle vaulting or rapid deceleration upon impact with the end section shown would be reduced. That does not mean to say that the potential is eliminated, only that the use of the end section is more feasible if the speeds are limited.