FWIW, the Westchester County newspaper (Journal News) had an
article today (Thurs, Aug. 1, 2013) about new safety policies. An excerpt (hopefully small enough to count as fair use):
Journal News wrote:
Metro-North’s plan to improve worker safety includes overhauling how track workers communicate with rail traffic controllers and testing new procedures for work zones. The four-month pilot program involves setting up physical barriers in work zones and attaching shunts to the track. Shunts are devices with stop signals to alert an approaching train operator of a construction area.
The article mentions that they will only use the shunts on the NH line because:
Journal News wrote:Metro-North officials have said using the devices [shunts] in areas with a third rail pose a danger to workers installing and removing them.
I'm not sure why adding shunts in 3rd-rail territory is more dangerous than any other work in 3rd-rail territory, but I'm not a track worker.