News

The explosion at the Packaging Corporation of America's corrugated cardboard mill in Wisconsin, which killed three workers and injured a fourth, is to be investigated by the US Chemical Safety Board (CSB).

The accident on 29 July occurred as workers were performing welding to repair the top of an 80-foot-tall storage tank, which contained recycled water and paper fibre.

CSB investigators visited the mill last week, examining the accident scene, conducting interviews and gathering evidence.

CSB chairman John Bresland said: "The CSB has noted that there have been previous tank explosions at paper mills during hot work and we will be closely examining the tragedy in Wisconsin to determine if there are similarities."

The investigation is expected to take a year to complete and is likely to involve further work at the site.

The CSB is an independent federal agency charged with investigating industrial chemical accidents.