Date of Graduation


Document Type


Degree Type



Davis College of Agriculture, Natural Resources and Design


Forest Resource Management

Committee Chair

Joe McNeel

Committee Co-Chair

Curt Hassler

Committee Member

Ben Spong

Committee Member

Ida Holaskova


This study examines logging safety audits to determine how different variables, and differing amounts of time between audits, affect the outcome of safety score performance. To collect the data for this study a three-page paper audit was used that examined five areas of the logging site which include: Personal protective equipment (PPE), general, felling, mobile equipment and, landing and loading.

The study analyzed 3 aspects of the audit which were the total score and the sub-categories of PPE and felling since they were the two heaviest weighted sections. The analysis only included audits that had a 5 percent or greater drop in score from the previous audit. Having at least 5 percent drop does not mean that a company had a failing safety score but does indicate that they are regressing. Three linear mixed models were developed, one each for total, PPE and felling score using the days in compliance per audit as the response variable. Number of personnel and season (warm/cold) were the fixed effects and the entity, as a surrogate for the logging company, was used as a random variable in models.

Predicted values of normalized days in compliance were calculated for each of the models with 2 through 10 personnel in both warm and cold seasons and organized into tables. They indicate number of days between the audits before the scores may decrease at least 5 percent of previous score. The PPE had the widest range of days in compliance per audit from 92 thru 154 days. The felling model had lowest range of days in compliance per audit from 86 thru 132 days depending on the input. PPE had the steepest slope of all the models.

Continued research should be completed with possibly pairing audit data with worker compensation claims or injury reports to examine the potential auditing on preventing accidents.