A number of tragic accidents involving escalators have once again drawn attention to the hazards posed by these ubiquitous fixtures of modern urban life.
Naima Rharouity, a 47-year-old mother of two, became the latest victim of a fatal escalator accident last week in Montreal when an item of her clothing became caught in the mechanism of the escalator, leading to her death by strangulation.
Less than a year ago, 42-year-old Seattle man Maurecio Bell was killed in a chillingly similar incident, when his shirt was caught in an escalator at the Seattle University Station Bus Terminal. By the time police and emergency workers arrived on the scene, Bell had already been asphyxiated.
The basic design for the modern escalator has changed little since it was first patented way back in 1892, still consisting of an angled conveyor belt structure which doubles back on itself. The chief source of hazard is the escalator landing platform, where the shifting steps are liable to snatch items of clothing, or even body parts, as they exit or emerge from the frame.
According to David Chan, director of the Centre for Information Leadership at City University London, despite the dangers they still pose, a big reason for the unchanged nature of the modern escalator is complacency, as there is "no incentive for escalator manufacturers to do anything different." The market is dominated by a mere handful of companies, including Otis, Schindler, ThyssenKrupp and Kone, and established international standards make any form of widespread reform very difficult to pursue.
There are alternatives, however, with Chan's City University colleague, mechanical engineering professor Jack Levy, developing a new form of escalator which is safer and easier to repair than its conventional peers.
The eponymous Levytator consists of a chain of curved modules which loop around in order to run in both directions without inverting themselves like a traditional escalator. In between the stairways, the module flattens out into a shifting walkway, completely omitting the need for potentially dangerous landing platforms.
According to Chan, who unveiled the elevator with Levy back in 2010, the Levytator isn't just safer than a conventional escalator, it's also significantly easier to maintain because the stairs can be removed individually. Standard elevators must be taken apart completely in order to perform repair work.
Until the Levytator takes off, however, the most expedient option may simply be to regulate the conduct of elevator riders in order to prevent them from engaging in rash or careless behaviour which heightens the chance of untoward events.
East Japan Railway, which has suffered from as many as 250 serious accidents a year, has encouraged riders to overturn the time-honoured courtesy of lining up on the left side of escalators, in order to leave the right side empty as a "passing lane." They are now encouraging riders to make a radical break with convention by standing on both sides of escalators in order to prevent people from rushing up or down their lengths with undue haste.