Abstract: On August 2, 2007, Employees #1 and #2 prepared to enter a 12 ft manhole to perform grouting work. Employee #1 collapsed after he entered, and Employee #2 went into the manhole to help him. As soon as Employee #2 was in the manhole, he collapsed, too. Both workers died of asphyxia. Employee #1 died later that day, and Employee #2 died on August 6, 2007. This was the company's first time performing sewer line work and Employees #1 and #2 entered the space without the required testing having been performed. The employer did provide a tripod winch system over the manhole, with a cable attached to a rescue harness. In addition, a Scott gas detector was used to detect any gases in the hole, but none was detected. The oxygen level was 8 percent near the top of the manhole and 3 percent near the bottom.