CA SB667

Requires railroad corporations to install wayside detector systems along all freight train tracks, with each system including a hot wheel bearing detector to scan for defects like hot bearings, dragging equipment, and shifted loads

Mandates maximum spacing between detectors: 10 miles for Class I carriers, 25 miles for Class II carriers, and 35 miles for Class III carriers

Restricts freight trains to 10 mph when traveling between non-compliant detector systems until passing a compliant detector that confirms no defects

Directs the Public Utilities Commission to adopt implementing rules, including minimum system requirements, alert processes for train crews, and inspection standards following detector alerts

Establishes a minimum penalty of $25,000 per violation and exempts Class II and III carrier tracks with speed limits of 10 mph or less