OCEAN CITY — After two severe accidents in three days, federal transportation officials will participate in an overall safety inspection of the William Preston Lane Bridge, or more familiarly, the Bay Bridge.

Around 8:30 p.m. last Friday, a 22-year-old Morgan Lake of Calvert County woman was heading eastbound on the Bay Bridge when her vehicle was struck from behind by a tractor-trailer. The force of the collision forced Lake’s vehicle up and over the guardrail on the eastbound bridge and it plunged 40 feet into the water below. Miraculously, Lake was able to swim from the vehicle to a rock jetty where she was rescued by emergency services a short time later.

Three days later on Monday, a minivan collided nearly head on with a pick-up truck pulling a trailer. The driver of the minivan was flown to Shock Trauma with injuries believed to be life-threatening. As of midweek, the victim’s condition had improved and he is expected to survive.

Earlier on Monday, AAA Mid-Atlantic sent a letter to the National Transportation Safety Board (NTSB) urging the federal agency to conduct an independent safety inspection of the twin Bay Bridges, even before the second accident occurred.

AAA Mid-Atlantic’s call for an inspection focused on the bridge’s protective restraint system designed to keep vehicles involved in crashes on the spans from leaving the roadway and going over the guardrails and barriers into the water below.

“No motorist using this facility should have to worry about going off the bridge in the event of an incident,” wrote AAA Mid-Atlantic spokesman Lon Anderson in a letter to the NTSB. “We think your agency’s investigation of this crash would provide assurance or lead to the changes necessary to provide motorists that peace of mind.”

In the letter to NTSB, Anderson said an independent review of the bridge’s restraint and barrier system was warranted to see if the specifications were being met, or if the specifications were adequate in the first place.

“This clearly raises questions about whether there was a failure of the specific restraint system used on the bridge, and whether it meets federal specifications, or whether the federal specifications for bridge barriers are inadequate to restrain a vehicle in this type of crash,” Anderson wrote to the NTSB. “If so, does this warrant an examination of the adequacy of those federal specifications?”

After a second serious accident on the Bay Bridge on Monday, U.S. Senator Barbara Mikulski joined the call to have the federal NTSB inspect and investigate the safety of the Bay Bridge complex. In her own letter to the NTSB, Mikulski voiced grave concern over the safety of the bridges and urged the federal agency to conduct a review.

“I’m more worried than ever before about safety on the Bay Bridge,” she said. “Traffic volume has increased and the velocity at which people travel has increased. One crash is too many, and now we’ve had two horrific crashes on the bridge in just a few days. That’s why I’m asking for NTSB to review the accidents and give Governor O’Malley, Transportation Secretary Jim Smith and myself recommendations on what needs to be done so it doesn’t happen again.”

Mikulski pointed out the sheer volume of traffic on the bridge during the summer season.

“This time of year, many Maryland families are crossing the Bay Bridge eager to begin their vacations on the Eastern Shore,” she said. “Others travel the bridge daily commuting to and from work on the western shore. No matter the destination, everyone should feel safe crossing the bridge and know that speed limits are being enforced.”

By Wednesday afternoon, the NTSB had responded to the requests for a review of the safety of the Bay Bridge and said in a statement it was sending investigators to assist local authorities to determine if there are any nationwide safety issues involved in Friday’s crash. On Thursday, two NTSB investigators were scheduled to meet with Maryland Transportation Authority (MDTA) officials to determine what, if any, recommendations should be made. For their part, MDTA officials said in a statement they embraced the help coming from their federal counterpart.

“We welcome the NTSBs involvement in our ongoing efforts to ensure the safety of motorists crossing the Bay Bridge,” said MDTA Executive Secretary Bruce Gartner in a statement on Wednesday. “We are constantly looking for ways to make crossing the span as safe as possible. From major physical upgrades to public information efforts designed to target distracted driving and speeding, our customers should know that were are committed to their safety and that we will work closely with NTSB staff during their investigation.”

According to the MDTA, the Bay Bridge is statistically safer than most state roads. The average number of crashes per 100 million vehicle miles traveled (VMT) is significantly lower on the Bay Bridge than it is on state roads. From 2008 to 2011, the bridge averaged 43 crashes per 100 million VMT, while the average for state roads was 166 crashes per 100 million VMT. The bridge carried roughly 28 million vehicles last year.