Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D4866 – Standard Test Method Technical Guide
📐 Scope and Application
This performance specification, designated D4866/D4866M, covers mixtures of emulsified coal-tar pitch (mineral colloid type), mineral aggregates, and optional polymeric admixtures. These formulations are designed as weather-protective and straight aliphatic hydrocarbon resistant coatings over bituminous pavements of airports, parking areas, and driveways. The values are stated in SI or inch-pound units, each system to be used independently, and may not be exact equivalents.
🧪 Material and Formulation Requirements
Component ratios and detailed specifications for mineral aggregate and optional polymeric admixtures shall be agreed upon between purchaser and seller. The base coal-tar emulsion must comply with Specification D5727/D5727M. Mineral aggregate must be natural or manufactured, composed of clean, hard, durable, uncoated particles free from dirt and organic matter. The optional polymeric admixture must be compatible with and enhance the performance of the sealer. Mixing water must be potable and free from harmful soluble salts, with a temperature of at least 10°C [50°F].
| 🟦 Component | 📏 Specification/Requirement |
|---|---|
| Base Coal-Tar Emulsion | Must meet D5727/D5727M |
| Mineral Aggregate | Clean, hard, durable, uncoated particles |
| Optional Polymeric Admixture | Compatible with emulsion, enhances performance |
| Mixing Water | Potable, temperature ≥10°C [50°F] |
⚙️ Physical Performance Standards
The mixture as applied must exhibit uniform consistency and be suitable for application on properly prepared surfaces. Application rate should be 0.4 to 1.0 L/m² [1.0 to 2.5 gal/100 ft²] without appreciable drainage on inclines up to 0.8% [0.1 in/ft]. Pavement and ambient temperature should be no less than 7°C [45°F] at application and for 12 hours thereafter, with no precipitation until dry.
| 📐 Property | 🎯 Requirement |
|---|---|
| Consistency | Uniform, suitable for application |
| Application Rate | 0.4 to 1.0 L/m² [1.0 to 2.5 gal/100 ft²] |
| Drainage on Inclines | No appreciable drainage up to 0.8% grade |
| Temperature Conditions | ≥7°C [45°F] for pavement/ambient, 12h hold |
💡 Tip: Ensure mixing water is at least 10°C [50°F] to prevent premature setting and ensure uniform consistency.
⚠️ Warning: Application should be avoided if temperature drops below 7°C [45°F] or if precipitation is expected within 12 hours to ensure proper curing and adhesion.
❓ Frequently Asked Questions
🔍 What are the temperature requirements for application?
Pavement and ambient temperature must be no less than 7°C [45°F] at the time of application and for at least 12 hours thereafter, with no precipitation until the emulsion has dried to ensure proper performance.
💡 What type of water is recommended for mixing?
Potable water free from harmful soluble salts is required, with a temperature of at least 10°C [50°F] to ensure proper mixing and application consistency.
⚡ Is polymeric admixture mandatory in the formulation?
No, the polymeric admixture is optional. Its use and specifications depend on agreement between the purchaser and seller to enhance performance of the sealer.
📌 What standard governs the base coal-tar emulsion?
The base coal-tar emulsion must meet the requirements of ASTM Specification D5727/D5727M to ensure quality and performance.