Original dataset (comma separated values, CSV) was downloaded from https://safetydata.fra.dot.gov/officeofsafety/publicsite/downloaddbf.aspx
The following ogr2ogr script converts the CSV file to GeoJSON, keeping several attributes that we wished to use for styling:
ogr2ogr -f "geojson" \
crossings-5.geojson \
CI_Crossings.csv -oo X_POSSIBLE_NAMES=Longitude -oo Y_POSSIBLE_NAMES=Latitude \