Delta Mist
Delta Mist® Penetrating Asphalt Spray Seal
Developed by the Warner Babcock Institute for Green Chemistry (WBI) under the leadership of Dr. John Warner, Delta Mist® is a liquid, non-toxic, spray-applied penetrating seal designed to restore and preserve asphalt pavements. By utilizing small molecules in a carrier oil, Delta Mist® interacts with oxidized components in aged asphalt, effectively reversing the effects of aging and extending pavement life.
Delta Mist is still undergoing testing by NCAT, and early results suggest that its effects on pavement longevity may extend beyond 4 years, showing promising long-term benefits.
Unlike other spray treatments, Delta Mist doesn’t clog the voids of open graded friction courses, allowing them to maintain the same high-void structure and friction characteristics after application.
Key Features:
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Deep Penetration: Reaches up to 3/8 inch into the asphalt surface to restore oxidized material by softening the binder and improving cohesion, which helps retard crack propagation.
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Eco-Friendly Composition: Formulated from plant-based materials, Delta Mist® is non-toxic and non-hazardous, ensuring safety for applicators and the environment.
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Preserves Surface Integrity: Does not require sanding or aggregate cover, maintains the visibility and reflectivity of traffic markings, and ensures no loss of surface friction characteristics.
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Quick Application and Cure Time: Applies easily without the need for heat or agitation and allows traffic to resume within 60–90 minutes, depending on ambient temperature and humidity.
National Center of Asphalt Technology (NCAT) Test Track Study Results
Delta Mist has undergone extensive testing at the National Center for Asphalt Technology (NCAT).
After six years and 20 million Equivalent Single Axle Loads (ESALs), it emerged as a top-performing seal and is the only product continuing into an additional round of testing, totaling 30 million ESALs.
This longevity demonstrates Delta Mist’s exceptional ability to extend pavement service life.
Key Statistics
- Minimal cracking (<0.2% block cracking after 20 million ESALs).
- Delta Mist extended pavement life by several years, maintaining performance beyond standard specifications.
- Depths remained at 3.8–5.3 mm, far below the 12.5 mm failure threshold.
- Initial drop in friction was minimal; recovery was rapid and sustained for 48 months.
- Binder viscosity consistently reduced, improving flexibility and reducing cracking susceptibility.
Glover-Rowe Index & Longevity
The Glover-Rowe Index is a measure of asphalt binder stiffness and cracking susceptibility. Specifically, it quantifies how oxidative aging affects the asphalt binder’s ability to resist cracking. A high Glover-Rowe Index value indicates increased stiffness and a higher likelihood of cracking.
Unaged Virgin Asphalt (Orange Line): Used as a baseline for flexibility and minimal oxidation.
PAV-Aged & Delta Mist-Treated Asphalt: Samples were treated with Delta Mist HR and subjected to aging conditions. Pressure Aging Vessel (PAV) testing at 305 PSI and 212°F simulated 7–10 years of oxidative damage.
Conclusions: Delta Mist-treated aged asphalt consistently demonstrated lower stiffness (lower Glover-Rowe Index) compared to unaged untreated asphalt.
At 50°F (critical for cracking susceptibility), the Delta Mist-treated sample was 8 times better than untreated asphalt, showcasing rejuvenation and flexibility.
Application Advantages
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Can be applied directly over existing striping, addressing areas with significant oxidation without the need for removal of thermoplastic markings or reflectors.
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No restriping or sanding required post-application, reducing labor and material costs.
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Roads can be reopened to traffic in as little as two hours, minimizing downtime and inconvenience.
- Applies by conventional distributors
- Does not require heat or agitation to apply
- Does not require sand or aggregate cover and the subsequent clean-up
- Does not negatively impact surface friction characteristics
- Does not require special handling as Delta Mist is a non-toxic, non-hazardous and non-regulated chemical
Medicine For Your Roads: The Science Behind Rejuvenation
The Link Between Curing Alzheimers and Delta S
The Alzheimer’s drug developed by Dr. John Warner works by targeting aggregates of proteins in the brain that bind to inorganic substrates, causing damage.
A small molecule was designed to slip between the organic and inorganic phases, disaggregate the harmful aggregates, and restore functionality. This breakthrough addressed the oxidative damage causing the disease.
Dr. Warner applied the same molecular concept to asphalt preservation. Asphalt binder, like the brain proteins, undergoes oxidation over time, causing it to become brittle.
Using a molecule with two components—one that interacts with asphalt and another that binds to aggregates—Delta S reverses the oxidation process in asphalt.
This rejuvenation process restores the original properties of the asphalt binder, allowing it to regain flexibility for workability and stiffen for durability.