In March 2010, SafetyAtWorkBlog reported on the deaths of two farmers in the rural town of Rainbow in Victoria. They died when a windmill they were transporting on a property made contact with overhead power lines. The deaths continue to be a difficult topic of discussion throughout the Wimmera-Mallee, as I found out over the Christmas holiday season.
The coronial inquest into the deaths of John and Michael Helyar began in Horsham in November 2010 and will continue in April 2011. Some of the inquest reports in the local newspaper make for harrowing reading but also provide an important insight into the decision-making process that occurs at the site of a workplace fatality and one that involves close friends.
The two articles are
Coronial inquest into tragedy at Rainbow, and
Inquest hears of agonising drama at Rainbow
The issue with some rural areas of is that the electricity supply system is a SWER system – Single wire Earth return. This consists of a single uninsulated wire strung between posts that are typically around 400 metres apart, and where there is a dip in the land maybe much further apart. This system in Victoria was installed as late as the mid 1960\’s. The risk to those moving around in paddocks where SWER wires are located, and to those operating planes or helicopters for agricultural purposes is the SWER system has a very low visual presence.
Another problem is that with dry soil, contacting the 12,500 volt wire generates a large electrical field around the object contacting the wire. The change in voltage across a walking pace can be sufficiant to kill someone.