During a recent weekend I spent a lot of time on our state highways and came to wonder why passing lane signs always say "400 metres to passing lane". Why 400m? Why not 500m? Vaughan Smith, Auckland.
What an interesting question. A Transport Agency spokeswoman has the following to say: New Zealand started metrication in 1969 with the establishment of the Metric Advisory Board (MAB) and completed the process on December 14, 1976. We signed the Geneva International Convention on Road Signs and Signals in 1949. Two systems were agreed: European, and Interamerican. (Now, there's a word I've never seen before).
New Zealand and Australia have traditionally followed American practice, hence the orange temporary and yellow permanent warning signs. Around 1969 all road signs with imperial units were gradually replaced by a metric equivalent. The 400m refers back to a soft metric conversion of the imperial quarter mile distance used throughout the US, NZ and Australia. The quarter mile relates to the time it was determined it took drivers to read, comprehend and decide any required action. It was based on the maximum speed limit in that particular area.
Q: Could you help clarify what the correct speed limits are in: a) Queen St, between Fort and Shortland Sts, heading away from the harbour - a limit of 50km/h or 30km/h? and
b) Elliott St, between Darby and Victoria Sts, is it 30 km/h or 10km/h? In both cases it seems the speed limit has been changed, but not the signage, with traffic from Fort St and Darby St having different speeds to the road they join. Steve Rymell, Auckland.
