Research
Advanced Odor Profile: Material Science for Detection Training Tools
Key Terms in Detection Training
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VOC (Volatile Organic Compound) – A small molecule that easily becomes airborne as a gas. Dogs don’t smell objects—they smell the VOCs those objects release.
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Odor Profile – The unique combination of VOCs released by a substance.
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Absorption – When odor molecules enter and get trapped inside a material.
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Adsorption – When odor molecules stick to the surface but don’t go inside the material.
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Off-Gassing – When a material emits its own VOCs (like glue, PVC, or certain plastics).
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Target Odor – The specific smell (VOC profile) the dog is trained to detect.
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Contamination – When non-target odors interfere with or change the smell environment.
How Detection Training Works (Simple Explanation)
Dogs have a sense of smell that is thousands of times more powerful than ours. When we train a detection dog, we’re teaching them to recognize and indicate the presence of a very specific scent—more accurately, a specific VOC profile.
The object (like a drug or explosive) releases VOCs into the air. The dog learns that these airborne molecules are meaningful, through training.
The training tools used to present these scents can affect the outcome of the accuracy of the detection capability of the dog. If the tool absorbs odors or emits its own VOCs, it can confuse the dog. The material can absorb odor that was not intended to be added to the training tool. We are using PETG, which is stable and non-porous by nature, to provide as consistent a training environment as possible.
Introduction: Why Material Science Matters in Scent Detection
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Scent Detection Relies on Purity & Consistency – Detection dogs identify volatile organic compounds (VOCs) from target substances. How much the material housing these scents interferes with the detection process affects the accuracy.
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Odor Contamination is Inevitable – No environment is truly scent-free. Dust, skin oils, humidity, and airborne VOCs can all influence scent trails. Even a handler walking toward and gesturing to a tool can influence a VOC trail.
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Material Selection Impacts Training Outcomes – The structure of a material (porous vs. non-porous), the extent of the porosity, its chemical stability, and its interaction with VOCs all affect how well a detection dog can isolate the target odor.
Odor Retention, Absorption, and Release: The Science
Absorption - Odor molecules penetrate the material's internal structure, causing long-term scent retention (common in wood, common in HDPE).
Adsorption - Odor molecules stick to the surface but do not enter the material itself (common in PETG, glass, metal). Adsorbed molecules are more easily cleaned off.
Off-Gassing - Some materials, like PVC, emit their own VOCs, leading to false positives and odor contamination, especially when exposed to heat.
PETG (Polyethylene Terephthalate Glycol) - Our Choice
Non-Porous - PETG does not absorb odor molecules internally, meaning it is resistant to retaining scent after proper cleaning. PETG is widely used in medical packaging due to its non-porous nature and low odor retention. While we do not use medical-grade certified PETG, the material we use shares many of the same beneficial properties—such as chemical stability and odor resistance.
petropackaging.com medical packaging
Chemically Stable - Resistant to most solvents, moisture, and temperature fluctuations, ensuring long-term consistency. This also makes PETG tools easy to clean.
HDPE (High-Density Polyethylene) - a commonly used choice
Moderate Odor Retention - HDPE is non-porous, however it can absorb odors over time, especially from oily or volatile substances, especially the recycled forms of HDPE.
Recycled HDPE Issues - Studies show recycled HDPE retains significantly more odors than virgin HDPE due to past chemical exposures.
In many cases, raw HDPE materials—especially high-grade or virgin HDPE—can be more expensive to source, which may increase the cost of manufacturing detection tools.
PVC (Polyvinyl Chloride)
Off-Gassing VOCs - some forms of PVC release volatile organic compounds (VOCs) over time, interfering with scent detection training.
Wood
Highly Porous - Wood absorbs and retains odors due to its cellulose structure, making decontamination nearly impossible.
Cross-Contamination Risks - Even with cleaning, residual odors remain trapped inside the wood grain.
Best Practices for Maximizing Training Accuracy
Rotate Training Aids & Locations - Prevents dogs from relying on non-odor cues like material texture or environment.
Control Environmental Factors - Humidity, temperature, and air circulation all impact odor movement. Using a variety of materials ensures a balanced training regimen.
Conclusion: Why We Use PETG in Our Training Tools
PETG delivers the level of performance we demand in our training tools. PETG checks every box we look for in a training tool material. It’s low in odor retention, non-porous, chemically resistant, and durable. It allows us to manufacture tools without glues, adhesives, or fasteners—reducing the risk of odor contamination. PETG also helps us keep production costs down, making high-performance tools more accessible to more handlers and teams. Every element of our design and material selection was chosen to help maximize accuracy, reliability, and longevity in scent detection training.
Lastly, variety is key and Detection Dynamics recommends using a variety of training aids, methods, location, and tools. This is the only way to ensure the highest level of accuracy for your detection dog.
Disclaimer for Distribution
This document is based on currently available scientific research, at the time of this research was done, and industry best practices. While every effort has been made to ensure accuracy, Detection Dynamics does not claim that any material is universally superior. Users should conduct their own assessments and adapt training methods based on individual needs. This document does not constitute legal or medical advice.