At some point, almost everyone asks the same question: Are mold detection dogs actually accurate?

I heard numbers thrown around confidently—ninety percent, ninety-five percent, “more accurate than testing.” I also heard the opposite: that dogs were unreliable, subjective, or easily influenced.

What I learned is that accuracy isn’t a single number. It’s a range shaped by conditions, training, and how results are verified.

Accuracy isn’t something dogs “have.” It’s something systems create—or undermine.

What Research on Detection Dogs Actually Measures

Most formal research on detection dogs—across many fields—doesn’t measure outcomes the way homeowners expect.

Studies typically look at:

• Whether dogs can discriminate a trained scent from controls
• How often they correctly identify known targets
• How often they falsely alert when no target is present

In controlled environments, well-trained dogs often perform impressively. But homes are not controlled environments.

Anchor sentence: Laboratory accuracy doesn’t automatically translate to lived-in buildings.

Why Mold Detection Is Harder to Study

Mold detection presents unique challenges compared to drugs or explosives. The “target” isn’t a single substance with a fixed scent.

Instead, dogs are often trained on:

• MVOCs associated with microbial activity
• Odor signatures from moisture-damaged materials
• Specific mold cultures used during training

That makes defining “ground truth” difficult. Growth can be hidden, inactive, intermittent, or already cleaned.

This is one reason accuracy claims vary so widely.

What Field Data Suggests

In real-world use, accuracy improves when mold dogs are used for what they’re best at: screening and direction.

Field experience consistently shows dogs perform better when:

• Used before invasive inspection
• Paired with confirmation methods
• Handled by neutral, well-trained handlers
• Interpreted with environmental context

When dogs are treated as verdicts rather than guides, perceived accuracy drops sharply.

Anchor sentence: Accuracy rises when dogs are used to narrow questions, not end them.

Why Accuracy Feels Inconsistent to Homeowners

What felt like inconsistency to me was often a mismatch of expectations.

A dog might alert where testing later looks “normal.” Or testing might show mold where a dog didn’t alert.

Those outcomes make more sense once you understand:

• What dogs are actually smelling
• How odor moves through homes
• Which conditions amplify or suppress detection

These pieces build that foundation: What Exactly Are Mold Detection Dogs Smelling and What Conditions Make Mold Detection Dogs More or Less Accurate .

False Positives and False Negatives in Context

No detection method is immune to error. The question is how error is managed.

Dogs may alert when:

• Residual odor remains from past moisture damage
• Microbial activity exists below visible thresholds
• Odor migrates from adjacent spaces

Dogs may miss issues when:

• Growth is dry or sealed
• Odor hasn’t entered accessible air
• Conditions suppress scent release

Understanding these limits prevents overreaction in either direction.

Anchor sentence: Error isn’t failure when it’s anticipated and accounted for.

Why Accuracy Claims Should Make You Curious, Not Confident

Absolute accuracy claims made me more cautious, not reassured. Especially when they weren’t paired with explanations of confirmation or limits.

The most trustworthy teams I encountered talked openly about:

• What their dogs are trained to detect
• What conditions affect performance
• How alerts should be followed up

Confidence paired with humility was a good sign.

A More Useful Way to Think About Accuracy

I eventually stopped asking whether mold detection dogs were accurate “enough.” I started asking whether they were being used appropriately.

When used for direction, they often improved the accuracy of everything that followed.

When used as a final answer, they often created confusion.

Accuracy improves when tools are placed in the right sequence.

— Ava Hartwell

Anchor sentence: The right tool at the wrong moment will always feel unreliable.