Seven people have been released from an Emporia hospital after an ammonia leak at the city's Tyson Foods plant.
Emergency workers were sent to the plant on Thursday.
KVOE News in Emporia reports that levels of ammonia at the site were registering at 10 parts per million, which is well below the lethal limit of 300 parts per million.
OSHA says workers can be exposed to a leak of 50 parts per million during an 8-hour shift.
Tyson spokesman Gary Mickelson says the leak temporarily disrupted production in part of the processing plant before it was found and stopped.
About six weeks ago Tyson Foods agreed to pay a nearly $4 million dollars civil penalty to settle alleged violations of the Clean Air Act, largely because of ammonia issues.
And in April 2009, an accidental release left one person injured.