State emergency officials say areas outside the evacuation zone surrounding a chemical plant in Conway that is burning should be safe. Officials say the size of the evacuation zone was determined based on worst-case scenarios of the danger of chemical fumes. Jennifer Gordon, spokeswoman for the state Department of Emergency Management, says the smoke cloud from the explosions and fire at Detco Industries looks threatening, but people outside the evacuation zone should not be unduly concerned. What was in the smoke wasn`t immediately known. The Emergency Management Department says federal documents from 2002 show that the plant has hydrofluoric acid, sulfuric acid and methanol on the premises, though it did NOT know if those chemicals were involved in the fire. Officials set up portable air-quality monitors in an effort to detect what was in the cloud. Detco makes industrial chemicals and aerosol products, such as cleaners and disinfectants.