FMCSA · Safety Measurement System register · Iowa

Controlled Substances/Alcohol in Iowa

• 592Violations recorded
• 25,803Registered carriers in the state
• 74,375State inspections addressing it

Driving under the influence of drugs or alcohol. Iowa carries 592 violations in this category, out of 14,736 recorded nationally, which places it 3 of 51 jurisdictions the register covers. Its share of the national figure is 0.040 as a fraction, banked by the build rather than turned into a ratio here. Nationally, a violation in this category carries an average severity weight of 8.55.

The state’s carriers by fleet size

• 1 power unit 13,594
• 2 to 5 power units 8,703
• 6 to 20 power units 2,156
• 21 to 100 power units 566
• 101 to 1,000 power units 106
• 1,000 or more power units 12

Other categories recorded in Iowa

• Crash Indicator 3,675
• Driver Fitness 5,712
• Hazardous Materials Compliance 361
• Hours-of-Service Compliance 24,242
• Unsafe Driving 21,925
• Vehicle Maintenance 62,002

Controlled Substances/Alcohol across every jurisdiction → Every category in Iowa →

Figures from the federal source files: EPA’s ECHO downloads, CMS provider files and the FMCSA census.

Counts from FMCSA SMS input files on data.transportation.gov: kjg3-diqy (Motor Carrier Census, 2,122,441 rows), rbkj-cgst (Inspection, 5,834,148), 8mt8-2mdr (Violation, 6,808,260), 4wxs-vbns (Crash, 255,582), p2mt-9ige (Out of Service Orders, 399,600); SoQL aggregates fetched 2026-09-16. The rank is taken over the jurisdictions this desk publishes, and the national figure beside it is the register’s own total for the category.