V/Line is currently actively managing the redesign, alteration and validation of the type 37 turnout to support restoration of standard gauge, 127 mm rim width, services.
Office of the National Rail Safety Regulator (ONRSR) – Safety Alert
The Office of the National Rail Safety Regulator has independently reviewed this occurrence and identified the higher risk of derailment through the wheel transfer area of some mixed and dual gauge turnouts for rolling stock having wheel rim widths of 127mm. ONRSR has issued an industry wide Safety Alert (RSA-2014-03).
While the ATSB is satisfied that the action proposed by V/Line will adequately address this safety issue in the context of type 37 turnouts, it is considered appropriate that all rail transport operators should be made broadly aware of the increased derailment risk in operating trains with narrow (127 mm) rimmed wheels through similar dual gauge turnouts.