By Tim Jimenez

PHILADELPHIA (CBS) — The Federal Railroad Administration issued new recommendations focusing on train speed at sharp curves, now four weeks since the deadly Amtrak crash in Philadelphia.

Investigators say Amtrak train 188 was traveling at more than 100 miles per hour at Frankford Junction, double the speed limit at the curve. And CBS News Analyst and former NTSB Chair Mark Rosenker says that was a bit of a wake up call.

“It’s very early in the investigation but clearly what they’re attempting to do is reduce the possibility of another over speed derailment like this,” Rosenker says.

The Federal Railroad Administration recommendations include adjustments to Automatic Train a Control systems at curves, more speed warning signs along the rails for operators to see, and the possibility of a second crew member in the cabin — right now it’s usually just the engineer.

The regulations are already in place for Amtrak trains, but this new round of recommendations affect commuter lines like SEPTA.

The BLET rail workers union had been calling for an extra person in the locomotive. This federal recommendation doesn’t necessarily mean adding on to the crew, but at least having one trained to know the curves and be in constant contact with the engineer.

“This is something that can be done immediately,” says Rosenker. “It will take a short period of time to add the additional signage. It will take a little bit of time to begin the process of adding a second crew member to the locomotive if that’s what they choose to do.”

This is all coming a week after a Congressional hearing on the Amtrak disaster and now four weeks since the derailment that left eight people dead and around 200 injured.