How are OOS rates calculated?

In this article

• How does a motor carrier receive an OOS violation?
• How are OOS rates calculated?

How does a motor carrier receive an OOS violation?

A motor carrier receives an Out-of-Service (OOS) violation when either the driver or vehicle is found to be in violation of critical safety regulations during a roadside inspection. The vehicle is then put immediately deemed out-of-service.

Common causes include driver-related issues such as Hours of Service (HOS) violations, falsified logs, impaired driving, or expired medical certificates. Vehicle-related causes typically involve serious defects like brake system failures, tire deficiencies such as insufficient tread depth or improper inflation, faulty lighting, or cargo securement failures. 

An OOS violation requires immediate cessation of driving until the identified safety problems are corrected. Failure to comply can lead to substantial fines, operational disruptions, and possible revocation of operating authority by the FMCSA.

How are OOS rates calculated?

The FMCSA calculates three separate OOS rates for each motor carrier: Vehicle, Driver and HazMat.

For Vehicle, the OOS rate calculation adds up all inspections that have an OOS violation in the Vehicle Maintenance BASIC for the two years of SMS data posted for the Motor Carrier. That number of OOS inspections is divided by the total number of inspections in two years. If that percentage is over the national average of 22.7% your vehicle OOS rate is considered in alert status.

For Driver, the OOS rate calculation adds up all inspections that have an OOS violation in the BASICs involving a driver which include Unsafe Driving, Hours of Service, Controlled Substances and Driver Fitness. That number of OOS inspections is divided by the total number of unique inspections in two years in those four BASICs. If that percentage is over the national average of 5.7% your vehicle rate is considered in alert status.

For HazMat, the OOS rate calculation adds up all the inspections that have an OOS violation in the HazMat BASIC for the two years of SMS data posted for the Motor Carrier. That number of OOS inspections is divided by the total number of inspections in two years. If that percentage is over the national average of 5.4% your HazMat rate is considered in alert status.