BATON ROUGE — The Interstate 10 bridge at Baton Rouge and seven other bridges across Louisiana were listed Thursday among critical spans with an "unknown level of risk of collapse" should they be struck by an ocean-going vessel.

The National Transportation Safety Board on Thursday released a report on the collapse of the Francis Scott Key Bridge in Baltimore and, in an appendix, noted 68 bridges nationwide that deserved attention. All of the bridges were built before industry guidelines were established in 1991.

It suggested to the Louisiana Department of Transportation and Development to assess the eight bridges and let the NTSB if the probability of collapse is above a standard set by the American Association of State Highway and Transportation Officials. The bridges made the list because the data isn't known.

The NTSB said further that if a bridge is found to be in danger from a vessel strike, it should develop a plan to reduce the risk. Similar advice to review bridges was given to transportation officials in other states.

The Louisiana bridges involved, and the year they were built, are:

-Huey P. Long Bridge, Jefferson Parish, 1936
-Crescent City Connection (original bridge), New Orleans, 1957
-Sunshine Bridge, Donaldsonville, 1963
-Israel LaFleur Bridge (Interstate 210), Lake Charles, 1964
-Horace Wilkinson Bridge (Interstate 10), Baton Rouge, 1968
-Hale Boggs Bridge, Luling, 1983
-Crescent City Connection (newer bridge), New Orleans, 1985
-Veterans Memorial Bridge, Gramercy, 1989