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Can you explain how safety event groups work in the Safety Measurement System (SMS)?One of the ways the SMS accounts for the differences between motor carriers and their operations is by placing carriers in safety event groups based on the number of safety events (e.g., inspections, crashes) in which the carriers have been involved. However, the Federal Motor Carrier Safety Administration’s foremost concern is safety and it accomplishes this by addressing the carriers who pose the greatest crash risk, irrespective of their industry segment.
Safety event groups enable the SMS to deal with the widely diverse motor carrier population, while ensuring that similarly situated carriers are treated with the same standards. Safety event groups do not compare carriers by the commodities they haul or their industry segment.
The tables below outline the safety event groups for each of the Behavior Analysis and Safety Improvement Categories (BASICs) and can be found in theSMS Methodology document.
Hours-of-Service (HOS) Compliance, Driver Fitness, and Vehicle Maintenance BASICs
Safety Event Group Category Number of Relevant Inspections* 1 3-10 (HOS Compliance) 5-10 (Fitness, Vehicle) 2 11-20 3 21-100 4 101-500 5 501+
Safety Event Group Category Number of Relevant Inspections* 1 5-10 2 11-15 3 16-40 4 41-100 5 101+
Controlled Substances/Alcohol BASIC
Safety Event Group Category Number of Inspections with Controlled Substances/Alcohol Violations 1 1 2 2 3 3 4 4+
- Combo – combination trucks/motor coach buses constituting 70 percent or more of the total Power Units (PUs).
- Straight – straight trucks/other vehicles constituting more than 30 percent of the total PUs.
Safety Event Group Category Combo Segment: Number of Inspections with Unsafe Driving Violations Straight Segment: Number of Inspections with Unsafe Driving Violations 1 3-8 3-4 2 9-21 5-8 3 22-57 9-18 4 58-149 19-49 5 150+ 50+
Safety Event Group Category Combo Segment: Number of Crashes Straight Segment: Number of Crashes 1 2-3 2 2 4-6 3-4 3 7-16 5-8 4 17-45 9-26 5 46+ 27+