(Reuters) - An initial check showed that Takata Corp 7312.T air bag parts and material involved in a deadly explosion in a truck in Texas last week were being shipped properly, a U.S. regulator said on Wednesday. A spokesman for the National Transportation Safety Board said the agency’s hazardous material team made the determination along with the Federal Motor Carrier Safety Administration, which conducted an initial survey of shipping documents.  The NTSB said it will decide in the next few weeks whether a deeper investigation is needed into the incident, which occurred on Aug. 22 near Quemado, Texas, and left one woman dead and four other people injured.. Such a probe was called for earlier on Wednesday by two U.S. senators, Richard Blumenthal and Edward Markey, both Democrats who are members of the Senate Committee on Commerce, Science and Transportation. The NTSB said in a statement that it has asked to review all documents related to the incident. “Initial indicators are that the materials were packaged properly. If the review of documents and other information shows cause to investigate, the NTSB will do so,” it said in a statement. Takata’s air bag inflators, which contain ammonium nitrate, have been linked to at least 14 deaths and more than 150 injuries and resulted in the largest vehicle recall in history. Prolonged exposure of the defective Takata inflators to hot and humid conditions has been found to cause air bags to explode with excessive force, spraying shrapnel into passenger compartments. The NTSB “must investigate this incident and determine whether this company took appropriate precautions,” said a statement by the senators, both Democrats. The senators noted that ammonium nitrate is also used in agricultural fertilizers and as an explosive for construction and mining industries. They said they want to protect against future incidents in highway shipments of the chemical compound. “We also seek answers on what steps must be taken to ensure other towns and communities aren’t endangered by the shipment of ammonium nitrate on our highways,” they said.          The NTSB, an independent safety investigation agency, focuses on studying accidents to determine if lessons can be learned that could lead to increased safety. The Texas Department of Public Safety is also investigating the incident, and the NTSB said it stands by to assist Texas officials upon request. 
Takata parts involved in blast were shipped properly: NTSB