National U.S. Chemical Safety and Hazard Investigation Board to explore fatal explosion at Givaudan facility in Louisville's Clifton neighborhood.

The U.S. Chemical Safety and Hazard Investigation Board also investigated a 2003 blast at the Payne Street facility that killed one worker.

A six-person team will arrive onsite Wednesday to investigate the Givaudan factory explosion that killed two workers.

Federal safety investigators are on site at the Givaudan Sense Colour plant in Clifton a week after an explosion killed two employees and injured 11. The U.S. Chemical Safety and Hazard Investigation Board announced its six-person team of investigators arrived at the scene Tuesday to begin its inquiry into the accident.

The family of Kevens Dawson Jr., who died in an explosion at a Louisville manufacturing facility last week, had urged officials to return to the wreckage after initially being told all employees had been accounted for.