Gas From Blast Kills Worker

A sewer worker was killed by poisonous gas 45 minutes after explosives were set off underground 50 feet (15.24 meters) away. The fatality occurred on a city utility construction site.

A crew working for one contractor set off the blast to break bedrock in preparation for laying pipe.

A worker on another crew went down 12 feet (3.66 meters) into a precast concrete manhole to grout the seams. Carbon monoxide gas from the blast seeped into the manhole, causing this worker to collapse. Two rescuers went in after him, and he was saved by one rescuer. The other rescuer collapsed and died.

Investigators found carbon monoxide had entered the manhole from the blast. The blasting product was nitroglycerin-based but contained other materials. Investigators said proper confined space entry procedures should have been used for the manhole worker and the rescuers to prevent exposure to poisonous gases and other respiratory hazards underground.

One lesson to be learned from this fatality is that working conditions can change quickly from apparently safe to lethal, possibly as the result of work going on nearby. On a multi-contractor project, your employer should be attending a daily safety meeting to co-ordinate activities of all on site contractors. In a case such as this fatality, a job safety breakdown might have identified the hazard and ensured safety measures were implemented.