When it comes to measuring mold indoors, accuracy matters—but so does accessibility. ARMI testing, or the American Relative Moldiness Index, was developed as a streamlined version of the ERMI test to help evaluate mold levels in water-damaged buildings using fewer species and a simplified index.
While ERMI analyzes 36 molds, ARMI focuses on 13 core species that are most commonly associated with indoor water damage.
ARMI offers a more affordable and faster alternative for homes or businesses that want actionable mold data without the full scope of ERMI.
Why ARMI Was Developed
ARMI was designed by researchers at the U.S. Department of Housing and Urban Development (HUD) as a more practical tool for assessing indoor mold exposure—especially in large-scale housing studies.
It uses the same scientific foundation as ERMI: MSQPCR (Mold-Specific Quantitative Polymerase Chain Reaction) technology, which detects mold DNA in settled dust samples.
The main difference? ARMI evaluates:
- A smaller group of mold species
- Uses a different mathematical formula to generate a moldiness index
- Prioritizes efficiency and simplicity over exhaustive detail
What Mold Species Does ARMI Measure?
ARMI tests for 13 fungal species divided into:
- Group A: Mold species commonly associated with water-damaged environments
- Group B: Mold species commonly found in indoor environments regardless of moisture
These species provide a clear risk picture of current or previous mold problems, especially in residential and multi-family housing.
The ARMI score is a relative number indicating how your environment compares to the average U.S. home. Higher scores indicate greater mold contamination.
When Is ARMI a Good Option?
ARMI is ideal when:
- You want a cost-effective assessment of mold risk
- You’re evaluating a rental property or new home
- You’ve had a minor leak or water event and want to rule out mold
- You need a simple benchmark before or after remediation
- You’re conducting routine screening for multi-unit housing
It may not capture as many species as ERMI, but it still delivers strong indicators of indoor mold exposure and is especially helpful in deciding whether deeper testing is needed.
How ARMI Compares to ERMI
| Feature | ERMI | ARMI |
|---|---|---|
| Mold species tested | 36 total (26 water-damage related) | 13 total (simplified set) |
| Developed by | U.S. EPA | HUD / researchers |
| Index type | Subtraction-based moldiness score | Relative moldiness index |
| Use case | Detailed investigation | Screening or follow-up |
| Testing method | MSQPCR | MSQPCR |
Both are based on the same scientific testing process but differ in depth and scope.
ARMI Testing at EnviroPro 360
EnviroPro 360 offers ARMI testing as part of our advanced mold diagnostics services for homeowners, landlords, and property managers across the CSRA.
We follow strict dust collection protocols and partner with AIHA-accredited labs to ensure your results are reliable.
When you work with us, you get:
- Full lab-certified results
- Clear ARMI scoring explained in plain terms
- Recommendations based on your home’s risk level
- Fast turnaround with optional post-remediation testing
Choosing the Right Mold Test
Whether you’re testing after water damage or preparing a home for sale, ARMI testing offers valuable insight into indoor air quality—without the cost or complexity of full-scale testing.
If you’re unsure whether ERMI or ARMI is right for your needs, our team can help you choose the best path based on your situation.
Schedule ARMI Mold Testing Today
Don’t guess when it comes to mold. Let EnviroPro 360 provide the science-backed answers you need with accurate ARMI testing throughout Augusta, Evans, North Augusta, and Aiken.
Contact us today to schedule your mold consultation or learn more about your indoor air testing options.
