Political leaders are calling for PG&E to install on its gas lines automatic shut-off valves to prevent or mitigate future gas line disasters.

Sounds like a good idea. Here’s an interesting snippet from a report of the NTSB, the agency that is investigating the San Bruno gas explosion:

The Safety Board believes that had an EFV been installed . . .  the valve would have promptly closed . . . . This closure would have likely prevented the release of gas sufficient to form an explosive mixture . . .. Additionally, an EFV would have prevented the continued release of gas during the emergency response activities and endangerment to firefighters and other emergency personnel.

The NTSB’s recommendation makes good sense.  What’s most interesting, however. is that the NTSB’s recommendation wasn’t issued as a result of the San Bruno Fire.  Rather, it was issued after the Santa Rosa fire.  In 1992.

Why hasn’t NTSB’s recommendation been implemented in the 18 years since the last fatal gas explosion?

As I wrote here, the NTSB has no power to require PG&E to do anything.  It can only recommend.  And, of course, PG&E is free to ignore those recommendations.

Santa Rosa Gas Explosion Safety Recommendation