The tank, located on the third basement level of the vessel, is 7.3 meters (23.9 feet) wide, 3.7 meters long and 10.5 meters high. The entrance to the tank is 1 meter wide. Authorities said it may take up to a week before further inspection results are out, because the tank was partially destroyed. In addition to the cause, authorities are also investigating whether STX Offshore and Shipbuilding Company violated any safety regulations. “Workers are granted permits to work in an enclosed space only after the company has confirmed there are no risks,” said an official of the Ministry of Employment and Labor’s Changwon branch office. “We’re going to check if it skipped any such procedures.” “A company safety check official granted the permit to the workers after checking the level of oxygen and other conditions inside the tank, around 8:35 a.m. Sunday,” said an employee of STX Offshore and Shipbuilding Company. The four workers - a 53-year-old surnamed Lim, a 52-year-old surnamed Kim, a 45-year-old surnamed Eom and a 33-year-old surnamed Park - were employees of a partner company of STX Offshore and Shipbuilding Company. “The last time I talked to my husband, he said he’ll be back around 4 p.m. after the painting work was done,” said Lim’s 47-year-old wife. “I wish I had taken him with me to my brother’s funeral on Sunday, then he would still be with me.” The vessel, some 90 percent complete, is to be built into a 74,000-ton oil-products carrier that is to be delivered to a shipping company in Greece in October.