They commonly have safety and worker training components.
Once used almost exclusively on very large projects that were either extremely isolated or that overwhelmed the local construction labor market, PLAs are now used on a variety of private and public projects.
The current report is possibly the broadest ranging, and most detailed studies of PLAs conducted to date. Although they lack good data on safety outcomes, interviews conducted in the study suggests that safety inputs are greater on PLA projects. Often PLAs include language establishing labor/management committees that deal specifically with safety and health issues.