Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D1214-10 – Standard Test Method Technical Guide
📜 Scope and Summary of D1214-10
ASTM D1214-10 (Reapproved 2020) specifies a standardized test method for determining the particle size distribution (sieve analysis) of glass spheres. These spheres are used as retroreflective media in pavement markings and in various industrial applications. The test method quantifies the gradation of the spheres to verify compliance with relevant specifications.
The procedure involves hand-sieving a dried specimen through a nested series of standard sieves, beginning with the largest opening and progressing sequentially through the specified sieves in decreasing size order. The weight of glass spheres retained on each sieve is recorded, and the cumulative weight and percent passing each sieve are mathematically calculated.
Values stated in SI units are regarded as the standard. This test method has been approved for use by agencies of the U.S. Department of Defense and was developed in accordance with international standardization principles established by the WTO TBT Committee.
⚙️ Required Apparatus and Sample Preparation
Accurate and reproducible sieve analysis requires careful adherence to the specified apparatus and sampling protocols.
| 🟦 Apparatus | 📏 Specification / Requirement |
|---|---|
| Balance | Sensitive to 50 mg (0.05 g) |
| Test Sieves | 200 mm (8 in.) diameter, conforming to ASTM E11 |
| Oven | Capable of maintaining 105 – 110 °C |
💡 Technical Note: The sieve cloth must strictly conform to ASTM Specification E11. Worn or damaged sieve cloth can introduce significant error into the particle size distribution results.
Samples are obtained by quartering or riffle sampling, as described in Practices D346 and D2013. For every shipment, at least two representative bulk samples of approximately 500 g each are taken from separate packages. The actual test specimen is a smaller portion reduced from this bulk sample.
| 📐 Sampling Parameter | 🎯 Specified Value |
|---|---|
| Bulk Sample Weight | ~500 g per sample |
| Shipment Sampling Ratio | 2 samples per 5000 kg (10,000 lb) or fraction thereof |
| Test Specimen Weight | 50 g (1.76 oz) of dry glass spheres |
📊 Sieve Analysis Procedure and Calculation
The execution of the test follows a precise sequence to ensure reproducible gradation data.
- Drying: Dry the specimen at a temperature of 105 to 110 °C to a substantially constant weight.
- Weighing: Weigh 50 g of the dried glass spheres to the nearest 0.1 g and place it on the sieve with the largest opening in the series.
- Sieving: Hand-sieve the specimen thoroughly, transferring the material that passes through to the next smaller sieve. Continue this process successively through all specified sieves.
- Calculation: Record the weight of glass spheres retained on each sieve. Compute the cumulative weight passing and the corresponding percentage passing each sieve.
📌 Important Note: The sieving process must be thorough enough to allow all particles smaller than the sieve openings to pass through, as described in the referenced practices, while avoiding damage to the spheres or the sieve cloth.
❓ Frequently Asked Questions
🔍 What is the scope of ASTM D1214-10? This test method specifically covers the sieve analysis of glass spheres used for retroreflective pavement markings and industrial uses.
⚡ What is the required specimen weight for the analysis? The test requires approximately 50 g of dry glass spheres, weighed to the nearest 0.1 g.
📌 How are representative samples selected from a shipment? Representative samples are selected using the quartering method (Practice D346) or a riffle sampler (Practice D2013). At least two ~500 g samples are taken per 5000 kg shipment.
💡 Why is the drying step critical to the test? Drying the specimen at 105 – 110 °C to a constant weight removes moisture that could cause clumping or add inaccurate weight, ensuring the sieve analysis reflects only the solid particle size distribution of the glass spheres.