hen Helsinki artificially shortened their Metro from 6 cars (135m) to 4 cars (90m) to save 50 million Euros on the Western Espoo extension, at least they put in proper stickers on the platform edge to demarcate the boarding zone:
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A roll of duct tape along the platform edge would've been better than what we did.
Ottawa got that right with the wall-mounted "Boarding zone/Zone d'embarquement" signage at the underground stations.
Seems like circular stickers similar to the Covid social-distancing ones would've been better.