slv.measurements.mobile.receptor_obs.CROSSING_STATES

slv.measurements.mobile.receptor_obs.CROSSING_STATES = ('route', 'line', 'stopped')

Location states whose CH4 counts for each receptor type (obs.parquet state). A crossing is a traverse, so on-track only; a dwell may be parked on a yard track, but indoor shed air is never ambient and is excluded for both.