I have been a fan of this fine sport for many years and through my working life have always been involved in construction. Over the last 4 years I have become involved with a vehicle restraint system developer and manufacturer and have become very familiar with the testing undertaken on barriers and the results required to allow barrier systems to be installed on public highways. In short whenever you test a barrier system you look for 3 things: 1 - Containment – Does it contain the test vehicle and stop the vehicle breaking through the barrier chain. 2 - Working Width – How much does the barrier move under impact. 3 – Impact Severity Level – This is slightly more technical and uses sensors on a dummy to measure the effect of the impact on the occupant of a vehicle. Impact Severity Level is a measure of the combined influence of ASI, THIV and PHD ASI (Acceleration Severity Index) characterises the intensity of the impact, and is regarded as the most important rate of impact on the occupants THIV (Theoretical Head Impact Velocity) describes the theoretical speed of the head colliding with an obstacle during impact. It has to be less than 33km/h PHD (Post impact Head Deceleration) value describes the head deceleration after an impact and has to be less than 20g (acceleration of gravity) The reason I mention all of the above is you will have probably noticed an increase in the amount of concrete barriers in the central reserve of motorways in the UK. This is to stop cross over incidents where HGV’s and the like break through the chain of barrier and onto the opposing carriageway. Manufacturers of concrete barrier have in the past struggled to achieve an acceptable level of Impact Severity due to the barrier being rigid e.g. it does not move under impact. There has also been a theme of our tracks changing from Post and Wire to more rigid barrier systems, it’s what the fans and drivers want, less damage to cars, less downtime for fence repairs etc. etc. but is it contributing to the increase in driver injuries? Some say the cars are getting too fast, are they really that much faster? We are now at a stage where driver safety devices are more complex with the introduction of HANS type devices etc. But my question is would a more flexible type of fence help in all aspects? There are other reasons why the HA have moved towards concrete barrier – less maintenance, longer useable life and this would be the same argument for our tracks and promoters. All I know is that you can still contain heavy, fast moving vehicles with a flexible type fence which reduces the impact on the occupant of vehicles. Slowing of cars would reduce the impact energy but not as significantly as making the impact softer. It may not be practical or feasible especially with tracks already making their barrier rigid but I just wanted to offer an alternative view in what appears to be an increase in impact type injuries.