Why aren’t There More Gas Line Safety Valves?

I read a very interesting article recently about gas line safety valves and the lack of their use. Apparently, the valves themselves cost $10-$15 for homes and small businesses and $200-$300 for larger buildings. Yet they are not on 90% of gas lines. What they do is shut off the gas if the lines are hit.

Since the late 60s there have been over 250 incidents where death and destruction could have been eliminated if the valves had been present. So why aren't they there? The gas companies are saying it would cost too much. It would seem to me that in the amount of time that these explosions have taken place that the percentages should be better in the use of this vital safety option.

Congress continues to look at these safety measures. Hopefully, more will be done to prevent future explosions. The Minneapolis Tribune has reported that:

148 cases the U.S. Transportation Department said could have been averted or diminished if valves were in place. The department released details on those accidents in response to a public records request from the AP. Applying the agency's criteria, the AP found 39 more. Another 84 cases were identified by NTSB investigators or mentioned in Transportation Department studies.

The need for safety is clearly there. Hopefully some action will be taken.