It's worth pointing out that basically every quartz watch ever is vastly more accurate than any watch that was ever certified as railroad grade.
https://en.wikipedia.org/wiki/Quartz_clock
A high accuracy quartz watch is accurate to 10 seconds per year.
https://www.watchtime.com/featured/high-accuracy-quartz-guid...
However, railroad standard was 4 seconds daily. That means that if a high accuracy quartz watch is never checked it may fail the standard within a year. However, a less accurate railroad chronometer will always be checked because it is less accurate.