By Rhiannon Riches
Rail safety workers requiring a clinical assessment of colour vision should be screened using 12 Ishihara plates in random order, according to the revised National Standard for Health Assessment of Rail Safety Workers.
Workers who get three or more plates wrong, fail.
‘Workers who fail the Ishihara screening test do not meet the criteria for Fit for Duty,’ the National Standard states.
The 2017 edition of the National Standard for Health Assessment of Rail Safety Workers was released by the National Transport Commission (NTC) on 25 November and will come into effect on 1 February 2017.
The Standard sets out criteria for road safety workers’ vision, including acuity, fields and colour vision.
The ability to identify and correctly interpret red, green and other coloured signals, flags and lights is necessary for the safe operation of trains, according to the NTC. This includes train drivers, heritage and tourist train drivers, signallers and shunters.
Workers who are required to see point sources but fail the Ishihara test may be further tested with a lantern test, preferably the Railway LED lantern test.
Workers who are required to see red and green colours on flat surfaces, such as controllers and workers using screen-based equipment, and fail the Ishihara test may be further tested by the Farnsworth D15 test.
The National Standard states that the Farnsworth D15 test should be applied three times, with two or more errors resulting in a fail.
‘Workers who were previously assessed by a rail transport operator under the former Standard using the Farnsworth Lantern may continue to perform their duties. However, if such a worker applies for a position with different colour vision demands or if the colour vision demands of the role change, they should be assessed against this Standard,’ the NTC states.
The NTC said this was the first revision of the Standard since the national law came into effect in January 2013.
‘Minor changes to the medical criteria align the revised Standard more closely with the recently updated Assessing Fitness to Drive Guidelines.’
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