One construction worker remained hospitalized after carbon monoxide sent [SIZE=2]nearly a dozen people to the hospital 3/15 at Giant Food Store in[/SIZE][SIZE=2] Forks Township, PA[/SIZE]. The store was evacuated about 9:30 p.m. Monday after carbon monoxide gas reached dangerous levels due to the use of a propane-powered tile cutter inside the store, authorities said.

Eleven people were sent to the hospital after the incident, at least three with potentially life-threatening conditions, but 10 have since been treated and released, said Tim Weis, the township's fire marshal.

At least one person had collapsed at the scene, police said.

"If you've gotten to the point where you become unconscious because of carbon monoxide poisoning, it could have affected your heart or it could have affected your brain," said Alex Rosenau, vice chairman of emergency medicine for Lehigh Valley Hospital.

The U.S. Occupational Safety and Health Administration is conducting an investigation, and Weis said the township will have no more input into the matter.

OSHA spokeswoman Leni Fortson said no information was yet available, and the investigation could take as long as six months.

Fire officials previously said subcontractor Diplomat Demolition was improperly using propane-powered tools inside a confined area, which they compared with running a car inside a closed garage.

An employee from the West Chester, Pa.-based company declined to comment when reached via phone.

Giant spokesman Christopher Brand could not say whether Diplomat Demolition would continue to be used for the construction because investigations are still ongoing.