Stephen Joseph, chief executive of the Campaign for Better Transport, has welcomed the announcement of a trial of season tickets for part-time workers in London.
He is calling for the scheme to be introduced quickly and rolled out across the commuter network.
More top news
The victim was hit as she crossed the road at a pedestrian crossing in Tulse Hill.
The 24-year-old was unarmed and the incident is not being treated as terror-related.
Some platforms have been taken out of service with disruption expected to continue until the end of the day.