odd question
A Red Route signifies that you cannot stop along it at any time when it is in force. It has nothing to do with casualties.
It has everything to do with assisting traffic flow
It is red route. Although this is a 'bus only' type lane in cities (esp London), there are loads of roads in the country that have signs like ' Red Route 20 casulties in the last 3 years'.
This is the sort of sign used http://www.northants.police.uk/default.asp?act ion=article&ID=2132