The employer should have a written practice and this written practice will outline their particular requirements. The ASNT recommended practice No. SNT-TC-1A recommends (for a high school graduate) 4 hours of classroom training + 1 month experience for a Level I and 8 hours of classroom training + 2 months experience for a Level II. With 2 years of college in engineering or science, a Level II only needs 4 hours of classroom training + 2 months experience. Level I requirements are unchanged.