Every employer of drivers who operate CMVs requiring a CDL (or Mexican or Canadian equivalent) must implement a controlled substances and alcohol testing program under Part 382 and 49 CFR Part 40. No driver may report for duty or remain on duty with a breath alcohol concentration of 0.04 or greater, use alcohol while performing safety-sensitive functions or within four hours before, use alcohol within eight hours after an accident requiring a post-accident test, or use or test positive for a controlled substance (unless prescribed and the physician advises it does not affect safe operation), and no employer with actual knowledge of such conduct may permit the driver to perform safety-sensitive functions. Refusal to submit to a required test counts as a positive. The employer must use a DOT-qualified testing laboratory, medical review officer and collection sites and apply Part 40 procedures.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.