When you’re a passenger on a U.S. commercial carrier, do you ever wonder if there’s anything hazardous on board with you?

If you've flown on U.S. Airways flights out of Hartford’s Bradley International Airport (BDL) the answer to that question might be disturbing to you.

The airline is facing nearly $400,000 in penalties for allegedly violating U.S. Department of Transportation Hazardous Materials Regulations.

Federal Aviation Administration (FAA) inspections found violations on a dozen flights to or from BDL between Feb. 26 and May 12, 2010.

In one instance, the Transportation Security Administration discovered, while inspecting passenger checked baggage, that US Airways had accepted an undeclared shipment containing ten disposable cigarette lighters filled with flammable gas. The FAA alleged the airline failed to notify the FAA of this discrepancy.

In another instance, US Airways offered an improperly packaged shipment containing wet cell batteries filled with alkali, a corrosive, for transportation by air on a US Airways passenger-carrying flight.

The pilots of the planes were unaware of the potentially dangerous cargo they were carrying; the FAA also alleged the airline failed to provide pilots with the required "accurate and legible written information" regarding 23 shipments of hazardous materials it accepted for transportation by air.

Proposed penalties against the company total $395,850.