[lloydde]

“When work crews pulled open a broken BART escalator at San Francisco's Civic Center Station last month, they found so much human excrement in its works they had to call a hazardous-materials team.“ (July, 2012) https://m.sfgate.com/bayarea/article/Human-waste-shuts-down-...

On the other hand although the following article mentions human waste multiple times, it seems likely the largest factor is age:

“The escalators had once been very reliable but are now showing their age, Lemon said. The Dublin/Pleasanton escalator, on the job since 1997, and the Millbrae escalator, in service since 2003, are both closing in on 20 years, which means it’s time for an overhaul, Lemon said.“

https://www.sfchronicle.com/bayarea/article/A-breakdown-of-B...

[ebikelaw]

I'm not denying the fact that the homeless crap on the BART stations. What I'm saying, and what the data from the new stations proves, is that it's not a factor and neither is age, nor exposure to rain. The new ones in the middle of nowhere with no rain are still unreliable, and there's no significant difference in available between the paid area and street escalators which you would expect to be different if transient excrement was the cause.

[lloydde]

The article [1] seems to provide data that disagrees, that the affected escalators have higher failure rates. What do you think is the motivation for these experts providing incorrect information?

1. https://www.sfchronicle.com/bayarea/article/A-breakdown-of-B...

[ebikelaw]

That analysis commits a variety of errors. For example, they rank Warm Springs as the most reliable with “only” 5 days of downtime in the last two years. Unfortunately at that time the station had only been open for 60 days.

[fyfy18]

For comparison, on London Underground the escalators are refurbished every 20 years, and replaced every 40 years.

https://tfl.gov.uk/campaign/tube-improvements/behind-the-sce...