Calculating CSA Scores

 In this section, learn how to manage your CSA scores.


How does Vigillo calculate CSA scores?

Vigillo is able to provide estimated national carrier and driver percentile rankings using the CSA Methodology. Vigillo uses a three-step approach to calculate CSA measures and rankings for customers - including peer groups and percentile ranks. 

Data is gathered on a monthly basis.

This data is run through a series of automated data cleaning and calculation algorithms by peer group developed by Vigillo based exactly on the published FMCSA CSA Methodology. This provides a first estimate result of BASIC measure and percentile ranking for all carriers in the Vigillo database. 

  1. Vigillo gathers FMCSA data for Vigillo customers. We calculate which peer group each customer is in for each BASIC by the number of average power units or the number of relevant inspections.
  2. Vigillo gathers FMCSA data for thousands of additional fleets, including all carriers in the largest peer group based on 500+ vehicles.
  3. As a third step, Vigillo reviews the actual FMCSA CSA data available to Vigillo customers in the nine pilot states for the "correct answer" from the FMCSA. We feed this data back into our calculations and re-run all numbers so that our calculated results are closer to the actual FMCSA result. We repeat this process over and over until Vigillo's calculated scores are nearly identical to the FMCSA results.


When do Vigillo scorecards get updated? 

Vigillo begins updating your scorecards as soon as we receive FMCSA's monthly (usually on or before the 10th of the month). Scorecards are completed within five business days after the monthly SMS update, depending on cooperation of FMCSA's systems. As soon as your scorecards are updated, Vigillo Support will email you an alert.


How does increased number of power units affect Scorecards? 

A change in a carrier's number of Power Units (PUs) applies to CSA through the change it makes in a carrier's AVERAGE number of PUs. Any change to the number of PUs on your MCS-150 would have a limited effect, initially, because CSA looks at Average Power Units (APU). Average number of PUs is the average of number of MCS-150 reported number of PUs from three time periods: currently, 6-months ago, and 18-months ago.

All other things being equal, increasing the number of PUs would likely improve your BASIC measures for the two BASICs that use APU:

  • Crash Indicator
  • Unsafe Driving

What time weights are used for violations and inspections in the CSA scorecards?

For CSA Scorecards, Vigillo uses the time weightings as described in the FMCSA's CSA published methodology: 

Carrier Time Weight under Carrier Safety Measurement System (CSMS) Methodology: 

  • 0 - 6 months = 3X 
  • 7-12 months = 2X 
  • 13-24 months = 1X 

Driver Time Weight under Driver Safety Measurement System (DSMS) Methodology: 

  • 0-12 months = 3X 
  • 13-24 months = 2X 
  • 25-36 months = 1X 

All carrier level information is computed using the Carrier (CSMS) time weights. If you are viewing information for a specific driver, then you are seeing the Driver (DSMS) time weighting.


How does the violation history of a driver impact carrier CSA scores?

Carriers are only evaluated on inspections and crashes associated with their own DOT number, so only violations that a driver receives while working for a carrier apply to that carrier’s Safety Management System (SMS) evaluation. Therefore, the driver’s violation history before the driver is hired and after the driver’s employment is terminated will not impact a carrier’s SMS results. However, even if a carrier terminates a driver, all of the driver’s crashes and inspection results that s/he received while operating for that carrier still apply to the carrier’s SMS evaluation for 24 months from the date of occurrence. Because the data is time-weighted, the effect of those occurrences on the carrier’s score will diminish over the course of the 24 months. 

Source: FMCSA CSA 2010 Website


What role do clean inspections play in CSA?

A "clean inspection" is when a relevant roadside inspection results in no violations for a particular BASIC. A relevant inspection is when the roadside inspector reviewed a particular area for evidence of violations—not all inspection types/levels look at all areas. 

For example, a clean inspection will lower the associated BASIC measure when a carrier has no violations related to a driver inspection levels 1, 2, 3 or 6 in the following BASICs:

  • Fatigued Driving Hours-of-Service 
  • Driver Fitness 
  • Controlled Substance/Alcohol

Similarly, when a carrier has no BASIC violations related to the Vehicle Maintenance BASIC and/or Cargo-Related BASIC from a Vehicle Inspection—levels 1, 2, 5 or 6—this clean inspection will lower the associated BASIC measure. 

The North American Standard Driver/Vehicle Inspection Levels are explained on the FMCSA webpage.

The Fatigued Driving (HOS), Driver Fitness, Vehicle Maintenance, Cargo-Related, and Controlled Substance/Alcohol BASICs all use relevant inspections as a denominator for assessment of carrier performance. For example, any time a driver is examined in an inspection, there is an opportunity for a violation that would impact the Driver Fitness BASIC. Since there is an opportunity for a violation, it is considered a "relevant inspection" for that BASIC. An inspection in which a driver was looked at with no Driver Fitness violations recorded i.e. a clean inspection would have a positive impact on the Driver Fitness BASIC.

Put simply, clean inspections help prevent the Fatigued Driving (HOS), Driver Fitness, Vehicle Maintenance, Cargo-Related, and Controlled Substance/Alcohol BASICs from becoming deficient, or help to improve those BASICs if they are already deficient.