State and federal workplace safety officials are investigating the fourth major accident since July at South Carolina's port facilities.

Michael Clarkin, a 34-year-old dockworker, was critically injured last week at the State Ports Authority's North Charleston terminal container storage yard when an empty shipping container fell on his vehicle.

International Longshoremen's Association Local 1771 president David Hogan told AP that Clarkin was an experienced dockworker and was parked 35-40 feet away from where containers were being loaded onto a truck for transport.

The container broke away from loading equipment and flew 40 feet through the air, Hogan said. The state Department of Labor and the federal Occupational Safety & Health Administration began their investigations last week.

Since July, four workers had been seriously injured or killed at state port facilities, the AP report said.

* On July 5, William Edward Holst Jr died at the Wando Welch Terminal in Mount Pleasant when a crane operator mistakenly lowered a container on top of him. Universal Maritime Services was cited because Holst was not wearing a reflective vest.
* The same day, union dockworker William Rouse was hurt at the same terminal when a crane operator lowered a container onto a ship and pinned him between two containers.
* On July 13, longshoreman Roson Simmons was killed at the Ports Authority's Georgetown terminal when three 1,000-pound rolls of paper fell off a forklift and crushed him.

OSHA planned to call in a team of regional investigators and maritime experts to examine all of the accidents and determine whether a correlation exists, or whether any safety procedures need to be changed.

Ports Authority spokesman Byron Miller said the port would conduct its own investigation of the latest incident. The ports have had good safety records, Miller said. In the 11 previous years, there had been just two fatalities, he said.