The National Ready Mixed Concrete Association's pervious certification is based on its book on the topic—plus experience. There are three levels of certification: Technician, which simply means you've passed the test, Installer (a new level as of September 2007), and Craftsman.
To get certified as an Installer or Craftsman, you first must hold ACI certification as a flatwork finisher, and you must pass the pervious written exam. For the Installer level, you must have worked on at least three pervious projects with a total size of at least 10,000 square feet. “We added this level because we recognized that there were only a handful of people who had the experience to be certified as a Craftsman,” says Vance Pool, NRMCA's senior national resource manager.
For the Craftsman level, you must show that you have 3000 hours of experience in placing pervious concrete (or 1500 hours and successful completion of a hands-on pervious concrete performance exam). The written exam covers:
- What a craftsman needs to know about pervious concrete: the basics
- Mix design: materials, testing, production
- Tools and ecquipment: the right tools for the size of the job
- Construction: forms, placing, finishing, curing
- Maintenance and troubleshooting: cleaning, preventing raveling and freeze-thaw damage, maintenance
The two-hour, closed-book exam has 50 multiple-choice questions; a passing grade is 70%. For more, visit www.nrmca.org/certifications/pervious.