Council-Certified Microbial Investigator

Prep Course

What is the CMI certification?

The Council-Certified Microbial Investigator (CMI) is an accredited certification offered by the American Council for Accredited Certification (ACAC).  It is designed for professionals that inspect properties for mold and bacteria issues. Our company, Indoor Sciences, offers a CMI preparatory course called the Microbial Investigator Course.

Although there are countless mold certifications available, most are unaccredited and do not increase your credibility as a professional. The CMI is a prestigious certification for those with 2-8 years of experience.  It will help you demonstrate to clients that you know how to identify mold, bacteria, and moisture issues by using a combination of a thorough inspection, moisture detecting equipment, and various samples when needed.

If you have more than 8 years experience, you should consider the CMC certification.

What are the CMI prerequisites?

The ACAC requires applicants for the Council-certified Microbial Investigator (CMI) to have 2 years of field experience in mold inspection.  The ACAC reduces the experience requirement to 1 year if you have a college degree in science, engineering, or related field. If you are new to the field and have less experience, you may want to target the non-accredited CSMI certification which requires no experience. Or if you have 8 years of experience, you should consider the highest level of mold inspection certification, the CMC.

Experience is documented by filling out project sheets which are part of the CMI application. If you have questions about your experience meeting the requirements, we suggest you contact the ACAC at 888-808-8381.

What is the exam like? 

The CMI exam is offered through computerized testing centers found around the world. There is also a newer option to take the exam online with a proctor viewing you through a webcam. 

The following are important details related to the CMI examination:

  • All multiple choice questions with four possible answers
  • 100 total questions
  • Passing grade is 75%
  • Duration: 3 hours 
  • Closed-book exam

How do I prepare for the CMI exam? 

Thousands of students have prepared for the CMI certification by taking our Microbial Investigator Course, which is sometimes referred to as the “CMI Course”.  In fact, we guarantee that students taking our course will pass the CMI! Indoor Sciences is a training provider of the Indoor Air Quality Association (IAQA) and has an excellent track record of helping students pass for this important certification. Because this is an accredited certification, we do not receive a copy of the exam.  However, for over a decade we’ve had a high degree of success helping students pass the CMI exam on the first try. 

The Microbial Investigator Course, which prepares you for the CMI exam, is both offered as an online and onsite course.  For more information including pricing and upcoming training dates, visit the Microbial Investigator Course.


Microbial Investigator Course