49 CFR §212.233

1. (a)An apprentice grade crossing and trespasser inspector shall be enrolled in a program of training prescribed by the Associate Administrator for Railroad Safety leading to qualification as a grade crossing and trespasser inspector. The apprentice inspector may not participate in investigative and surveillance activities, except as an assistant to a qualified State or FRA inspector while accompanying that qualified inspector.
2. (b)Prior to being enrolled in the program the apprentice inspector shall demonstrate:
   1. (1)Working basic knowledge of electricity;
   2. (2)The ability to use electrical test equipment in direct current and alternating current circuits; and
   3. (3)A basic knowledge of highway-rail grade crossing inspection and maintenance methods and procedures.